Seabuckthorn Leaves Increase PPAR-Alpha & PPAR-Gamma Expression, Keep the Liver Fat Free and Fatty Oxidation Up. Plus: PPARs - High or Low? How Are They Supposed to Be?

This time, the magic is in the leaves, not the fruits or kernels. And it's dose dependent. With an almost linear increase from 500-1,000mg/kg

Honestly, I don't think that it is coincidence that many of the most promising medical plants are shrubs that live on barren soil, like sand dunes and cliffs and are full of thorns as well as innate polyphenolic defense mechanisms. Whatever the "evolutionary" basis may be, if we go by the beneficial metabolic effects, researchers from the Department of Food Science and Human Nutrition at the Chonbuk National University in the Republic of Korea, it appears worth going through all the traditional used folk medicine across the world and identify which of them work, how they work and whether they may already have what it takes to get rid of one or the other of the typical Western diseases.

In the case of the ethanolic extract of seabuckthorn (Hippophae rhamnoides L) Pichiah et al. used in their most recent experiment, this would be ameliorative effects on weight gain through down-regulation of adipogenic and lipogenic gene expression.

Less weight gain more fatty acid turnover, better glucose management and leptin sensitivity

The ameliorative effects on the detoriation of glucose metabolism, the reduced but still significant weight gain of the 60% fat diet (additional fat 100% from lard) and the profound overexpression of leptin, which is indicative of the fact that the mice developed full-blown leptin resistance within the 13-weeks of HFD administration, were all ameliorated to a greater degree in the high dose seabuckthorn leaf extract group (human equivalent  ~6.5g/day).

Figure 1: Effect of the different diets on weight gain, visceral fat weight, feed intake and energy intake (left; data expressed relative to control diet); effects on blood sugar (AUC in glucose tolerance test) and leptin (Pichiah. 2013)

The differences between high and low dose supplementation of the extract which had been prepared by

"[...] by soaking the dried, powdered leaves in 70% ethanol for 7 days at room temperature. Then the extract was concentrated by evaporating ethanol using a rotary vacuum evaporator (N-N Series, EYELA, Tokyo, JAPAN) set at 60°C and 100 hPa" (Pichiah. 2013)

were even more pronounced, when we compare the effects on fatty acid oxidation (CPT-1), the PPAR-alpha and -gamma values.

Figure 2: Carnitine palmitoyltransferase I (CPT1), PPAR-alpha & -gamma activity and triglyceride & cholesterol content in the liver (left; expressed relative to rodents on normal chow). Histology of liver sections at 200x magnification for the different diets (Pichiah. 2013)

What's yet most striking is however that the liver - the organ that's so heavily involved in the etiology of insulin resistance - was virtually "fat-free" in the rodents who received the 1,000mg/day dose. The total triglyceride and cholesterol content was even lower than in the mice on the normal diet and the overall darker staining in the slices on the right of figure 2 is only further evidence of the beneficial effects the seabuckthorn extract had on the liver histology.

The effects of a 5% conjugated linoleic acid diet do actually resemble that of lipodystrophy, i.e. pathological fat loss and inability to store body fat. Strange, no? Well that's PPAR-gamma (read more).

PPAR-gamma? Wasn't that what you actually wanted to avoid? In a way this is right, since PPAR-gamma and even alpha are somewhat Janus-faced molecules (overview for PPAR-alpha). As beneficial as their expression in the liver may be, both inhibit the oxidation of glucose. PPAR-gamma is also involved in the maturation process from pre-adipocytes to mature adipocytes, increases lipogenesis in white adipose tissues, decreases the cell surface fatty acid transporter on muscle cells and increases glucose uptake in adipocytes (exclusively). All that is healthier than fat clogging your liver, but it's not exactly something that will make you leaner if you are work out and consume a junk-free diet.

In fact, the PPAR-gamma suppressing effects of the trans-10, cis-12 isomer of conjugated linoleic acid (CLA; cf. Kennedy. 2008) are actually what what produces such profound effects, as they were observed in the study I discussed on July 22, 2013 (see link beneath the image of the mice).

TTA and fish oil are potent antagonists of liver PPAR expression. With the uncoupling and anti-inflammatory effects of TTA being the key to unleash & maintain fat-burning (read more).

Bottom line: It appears as if the liver is - once again - emerging as a central player in "sick obesity", meaning being fat and sick and not just fat. Which reminds me of yesterday's post on Gluten and the development of metabolic disease, where fatness is no criteria, at all. The expression of the "liver cleansing" PPAR-gamma enzymes on the other hand was.

This in turn reminds me of the effects of fish oil and TTA (a pan PPAR-activator), which - despite their questionable use as a long-term intervention can in fact stimulate intra-hepatic fatty acid oxidation to levels which are so high that oxidation rates in and out of itself could bring about some problems.

Other nutritional factors you should take into account are choline (a deficiency will actually cause fatty liver disease; read more about choline) or taurine. And on the endocrine side of things you want to keep an eye on optimal DHEA levels (read more about its effects on PPAR-gamma), thyroid hormones, testosterone and estrogen (Nemoto. 2000).

References

• Kennedy A, Chung S, LaPoint K, Fabiyi O, McIntosh MK. Trans-10, cis-12 conjugated linoleic acid antagonizes ligand-dependent PPARgamma activity in primary cultures of human adipocytes. J Nutr. 2008 Mar;138(3):455-61.
• Nemoto Y, Toda K, Ono M, Fujikawa-Adachi K, Saibara T, Onishi S, Enzan H, Okada T, Shizuta Y. Altered expression of fatty acid-metabolizing enzymes in aromatase-deficient mice. J Clin Invest. 2000 Jun;105(12):1819-25.
• Pichiah PB, Moon HJ, Park JE, Moon YJ, Cha YS. Ethanolic extract of seabuckthorn (Hippophae rhamnoides L) prevents high-fat diet-induced obesity in mice through down-regulation of adipogenic and lipogenic gene expression. Nutr Res. 2013 Nov;32(11):856-64.

Beyond Celiac: Study Sheds New Light on Obesogenic Effects of Gluten - Are PPARs & Bacteria Both Involved?

Cornflakes peanut butter cookies - guaranteed not gluten free ;-)

With Christmas Eve being over, and grandma's cookies, Christmas stollen, and all sorts of other stuff from the bakery in front of you (literally), Christmas Day may actually prove to be a way more "dangerous" than Christmas Eve - not just because of the total amount of calories, but also because of the low satiety effect of these sweet treats.

A recent paper by scientists from the Universidade Federal de Minas Gerais in Belo Horizonte in Brazil does now point to another reason you better give those bakery products a wide berth - not just, but especially with the energy overshoot on Christmas day: Gluten!

Study confirms for the first time what scientists and laymen alike have been speculating about

In what the scientists claim is the first well-controlled study of the effects of gluten intake on metabolic health in a non-celiac, but Western-style diet scenario, Fabíola Lacerda Pires Soares and her colleagues put two groups of C57BL/6 mice on identical, iso-caloric high fat (hypercaloric) diets that differed only in terms of the amount of gluten that was added to the chow (0% gluten vs. 4.5% gluten).

Interestingly, the gluten diet did not influence any of the usual suspects, like food intake, total fat-free mass, fecal lipids excretion, blood lipid profile, blood total protein and ectopic (liver and muscle) lipid concentration (if you look closely you will realize that the gluten-free group actually had higher TRIGs, although the difference did not reach statistical significance).

Figure 1: Usual suspects and closer look at the effects 8 weeks gluten supplemented vs. gluten-free diets had on serum markers of metabolic syndrome and visceral fat parameters (Soares. 2013)

The data in figure 1 (right) does yet also show that the gluten content of the diet did nevertheless have a significant impact on the total body mass, visceral fat mass, lipid content and most importantly the adipocyte size.

Figure 2: Absolute adipokine levels (left) and fasting glucose and insulin levels, as well as Homa-IR (Soares. 2013)

Add to that the blunted expression of the anti-inflammatory and anti-diabetic fat hormone adiponectin and the increased the >5x higher expression of leptin (figure 2). And mix that with the reduced expression of PPAR-alpha and gamma of which Soares et al. argue that they may well be the key factor in the detrimental modulatory effect the addition of gluten had on the visceral fat structure and the lowered expression of the fat liberating enzymes LPL and and HSL, as well as reduced levels of the fat burning proteins ACC and CPT-1 (figure 3).

Figure 3: PPAR-alpha, -gamma, LPL, HSL, ACC and CPT-1 expression compared to rodents on regular chow (left); crown like structures in stained slices from visceral fat, inflammatory markers TNF-alpha and IL-6 (Soares. 2013)

So, even if the initially mentioned blood markers (aka the usual suspects) would suggest that both the gluten-consuming and gluten-free rodents were similarly bad off, the profound difference in inflammatory markers within the adipose tissue and the presence of comparatively many necrotic and inflammatory adipocytes in the crown like structures stand in line with increases in HOMA-IR, fasting glucose and insulin and an already compromised glucose clearance which are well-known harbingers of the metabolic syndrome.

These observations do not simply shed a whole new light on a hitherto largely ignored contributer to the etiology of the metabolic syndrome, they do also show that one of the reasons it has not been identified before is an over-reliance on BMI, total fat mass and serum lipids in the early stages of diabesity.

Reardless of whether the gut microbiome is part of the mechanism by which gluten predisposes the development of metabolic syndrome. Eating more inulin- and beta-glucan rich foods like Jerusalem artichokes, agave, bananas, onion, steel cut oats, wild yams, yacon, etc. certainly won't hurt your efforts to get lean, stay lean and leave the role of the obese diabetic to the other (read more)

Bottom line: The study at hand provides a good reason to limit your intake of "healthy whole grains" and other gluten containing foods, regardless of whether you suffer from celiac or not. Whether the established detrimental effects of gluten on the integrity of the intestinal wall and the increased leakage of bacterially produced endotoxins from the highly unfavorably changes in the gut microbiome in response to the high fat diets (Hildebrandt. 2009) are part of, or even the primary cause of these observations still has to be elucidated. The same goes for strategies to counter the translocation of the endotoxins across the gut lining (cf. "Shedding some light on the leaky gut") and the dose response relationship between the total amount of gluten in your diet and its effects on your metabolism. With 7% of pure gluten, it goes without saying that you would basically have to live of wheat in order to get to anywhere similar amounts of gluten in the diet... that said: Is it possible that the effects occur only in the presence of the high fat diet? After all, this alone has been shown to favor a pro-inflammatory gut microbiome.

You see there are enough questions to be answered in 2013 and the SuppVersity is going to be the place you will read the respective answers first ;-)

References:

• Hildebrandt MA, Hoffmann C, Sherrill-Mix SA, Keilbaugh SA, Hamady M, Chen YY, Knight R, Ahima RS, Bushman F, Wu GD. High-fat diet determines the composition of the murine gut microbiome independently of obesity. Gastroenterology. 2009 Nov;137(5):1716-24.e1-2.
• Soares FL, de Oliveira Matoso R, Teixeira LG, Menezes Z, Pereira SS, Alves AC, Batista NV, de Faria AM, Cara DC, Ferreira AV, Alvarez-Leite JI. Gluten-free diet reduces adiposity, inflammation and insulin resistance associated with the induction of PPAR-alpha and PPAR-gamma expression. J Nutr Biochem. 2013 Dec 17.

Fat Loss Principles That Work: 10g+ of EAAs W/ Every Meal. Do Energetic Costs of Protein Synthesis Trigger This Effect?

EAAs beyond whey: It may not necessarily look like this, but this salad (repicecorner) is an EAA power horse with cheddar cheese (25% protein, 0.49 EAA / P ratio), tuna (in oil, 29%,  0.45) and kidney beans (9%, 0.45). You see, it does not always have to be chicken breasts or whey to get beyond the 10g+ EAA threshold, I have repeatedly suggested as one of the fundamental rules of dieting for weight loss, maintenance and muscle gain.

Many people take it for granted that you become fat, when you get old. If you look at the statistics, you could even make a point that obesity has some protective effects with esp. with respect to CVD mortality. Scientists call this the "obesity paradox" (Kastorini. 2013). What's particularly paradox, at least in my humble opinion, is yet not the phenomenon itself, but rather the fact that it gets smart scientists derailed from working on useful dietary and exercise interventions to prevent the development of heart disease, cancer, metabolic syndrome etc. in early years. Instead, they argue ex-post, i.e. when the baby has already been thrown out with the bathtub by comparing sick lean (in parts even cachectic) and sick "obese" people, why their statistical shenanigan that's based on the useless BMI produces paradoxical results. And that, when studies such as the one Jacobs et al. did in 2010 clearly show that 50+ year old men and women with waist circumference >120cm and >110cm, respectively, have 2x higher all-cause mortality risk than their lean peers - irrespective of BMI (Jacobs. 2010)!

To get lean and stay lean, yet not thin and skinny fat is therefore a challenge everyone...

... from the child in the Kindergarten to the obese granny in the nursing home is facing. Against that background a previous study by Loenneke et al. comes to mind. The results of their analysis, which were published in Nutrition and Metabolism in January 2013 clearly show that the amount of times people eat meals with a 10g+ EAA content per day was inversely related to percent central abdominal fat (Loenneke. 2013). In previous studies EAAs have also been shown to improve glucose clearance without increases in insulin and in the absence of effects on the fat burnin and health promoting expresion of AMPK-alpha2 in skeletal muscle tissue (see "EAAs Stimulate Muscle Glucose Uptake by Exponentiating Insulin's Effect on GLUT4 Expression"). With the advanced publication of a study by Coker, Miller, Schutzler, Deutz and Wolfe in the online verison of the Nutrition Journal a couple of days ago, the notion that EAAs have a particularly beneficial effect on fat loss - in this case in obese elderly individuals - gets further support from a well-controlled randomized trial (Cooker. 2013).

EAA-rich protein increases fat loss to a greater extent than low EAA protein

The researchers from the Center for Translational Research in Aging and Longevity and the University of Arkansas for Medical Sciences in Little Rock, AR, USA randomized 12 elderly individuals (mean age 69 years) to an 8 week, caloric restriction diet utilizing equivalent caloric meal replacements (~850 kcal/day; the exact nutrient composition can be found in figure 1) + ~400kcal from solid foods (total intake: ~1,250kcal/day; the subjects were free to chose their solid meals but were provided with a list of examples the should pick from, if possible).

Figure 1: Macronutrient composition of the meal replacements used in the study (Cooker. 2013)

The diet was designed to induce a 7% weight loss in two months. And while both,  the rate of weight loss (~1.6lbs per week), as well as the relatively high caloric deficit are certainly appropriate for someone with a 30+ BMI and ~40% body fat, leaner people will fare better with a less pronounced kcal deficit or (alternatively) have to add some strategically planned refeeds to the equation in order to minimize the loss of lean mass and, more importantly, avoid the ensuing reduction in energy expenditure (for the obese, the latter is actually less of the problem, because the downsides of being calorically deprived are at least partly counglucose tolerance and leptin sensitivity with every gram of body can actually help the body recognize that there is still plenty of energy that has just not been available (glucose) or "visible" (fat) before).

Figure 2: Changes in lean and fat mass (kg, left) and fractional protein synthesis rates (FSR) in participants receiving iso-caloric meal replacements with identical macronutrient compositions (see figure 1), but different amounts of essential amino acids (EAAs) content (Coker. 2013)

As the data in figure 2 goes to show you even the obese individuals in the study at hand lost a non-negligible amount of lean mass - unfortunately the body composition was measure with a sophisticated, but still body impedance based device, the trends are still accurate, but it is questionable in how much we are actually talking about ~2 and 2.5kg of muscle mass (figure 2, left), because somebody's "lean body mass" does obviously include more than just skeletal muscle.

When it comes to supplements, we are often like children on Christmas eve. About all the new stuff we get we tend to forget our former favorite and often way more fun to play with toys. Don't make this mistake and ditch your PWO whey (personally, I like a ~1.5:1 whey + micellar casein mixture) for EAAs, they don't come close... read more

Be that as it may - since the before and after values were taken with the same device the changes should be correct, so that both the slightly yet not statistically significantly ameliorated loss of lean body mass and, more importantly, the significantly higher degree of body fat loss in the EAA meal replacement (EAAMR) group speak in favor of the 5 servings of a the 170 kcal, 6g EAA per day. Moreover, "the sparing influence of muscle loss might have been demonstrated with a larger sample size", so that you can take it for granted that the preservation of precious muscle mass is an advantage of being choosy with your protein sources and preferring those with higher over those with lower essential amino acid contents.

On a related note: I don't know if you noticed, but with a total energy content of 850kcal and 30g EAA these 5 meal replacements did in fact have exactly those 10g+ of essential amino acids, I have repeatedly recommended to have with each of the 3 meals most people consume in the course of the day.

In all fairness, it should also be mentioned that despite not being significantly different at baseline, the body fat percentage of the subjects in the EAA meal replacement group was ~3% higher to begin with.This may seem irrelevant, since figure 2 compares lean mass and fat mass as absolute changes and not their percentages, but in the end, the amount of fat you you can drop within a given time-frame decreases with lower body fat percentages.

Do the energetic costs of protein synthesis drive fat loss?

Another interesting observation Coker et al. made is the close association between fat loss, on the one hand, and increased protein synthesis (55%), on the other hand. The researchers take this as an incentive to do one of the of the much loved calories in vs. calories out calculation and come up with the following hypothesis:

"Acute administration of EAAMR did promote a significant increase in skeletal muscle protein FSR compared to CMR. Assuming that the energy cost of protein synthesis is 3.6 kJ/g and the baseline GAIA-derived lean tissue mass was 56.4 kg for EAAMR and 54.4 kg for the CMR, we can extrapolate that the overall energy discrepancy between the two groups was roughly equivalent to 27,170 kcal or 3.5 kg of weight loss across the entire caloric restriction-based weight loss paradigm. Based on the amount of total lean mass in each group, this value takes into account a consistent intervention structure of five servings/day across an eight week period. In short, these calculations suggest that differences in the source of intact protein/formulation of EAA may have a significant influence on diet-induced energy expenditure that coincides closely with the greater reduction of adipose tissue in EAAMR compared to CMR." (my emphasis in Coker. 2013)

I usually discard fallacious calculations like this one if they are not highlight the stupidity of trying to eat exactly as much as some funky formula + the figure on your treadmill, pedometer, heart rate monitor or whatever fancy tool you may use to "measure" your energy expenditure suggest you would have burned in the last 24h. In this case, however, I made an exception, because I feel that the notion that protein quality is one of the myriad of parameters that are missing from this foolish calculation is important, for lean and obese people from all age groups who are trying to shed body fat.

Bottom line: The take away message of the study is in the end identical to the previously mentioned study by Loenneke et al.: Make sure you hit the 10g EAA threshold with each and every of your meals, if being lean and muscular not skinny yet fat is your goal.

References:

• Coker RH, Miller S, Schutlzer S, Deutz N, Wolfe RR. Whey protein and essential amino acids promote the reduction of adipose tissue and increased muscle protein synthesis during caloric restriction-induced weight loss in elderly, obese individuals. Nutr J. 2013 Dec 11;11(1):105. [Epub ahead of print]
• Jacobs EJ, Newton CC, Wang Y, Patel AV, McCullough ML, Campbell PT, Thun MJ, Gapstur SM. Waist circumference and all-cause mortality in a large US cohort. Arch Intern Med. 2010 Aug 9;170(15):1293-301.
• Kastorini CM, Panagiotakos DB. The obesity paradox: methodological considerations based on epidemiological and clinical evidence--new insights. Maturitas. 2013 Jul;72(3):220-4.
• Loenneke JP, Wilson JM, Manninen AH, Wray ME, Barnes JT, Pujol TJ. Quality protein intake is inversely related with abdominal fat. Nutr Metab (Lond). 2013 Jan 27;9(1):5.

Grass-Fed Pork? Not Really. Still the Difference in Fatty Acid Composition & Micronutrient Content Are Profound & Not Accounted for by Food Databases - Let Alone Epidemiology

You often hear that pigs are pretty closely related to us humans, but "are all pigs created equal"? Or what may be a more appropriate question for the SuppVersity: Is all pork really created equal?

If you like databases like nutritiondata.com or the USDA's very own detailed nutrient database in order to evaluate whether your diet is actually delivering all the nutrients you need you are probably missing half of the picture. At least as far as the more sophisticated details go, a recent paper from the Instituto de Ingeniería de Alimentos para el Desarrollo at the Universidad Politécnica de Valencia clearly indicates that you would at least have to consider what the animals, in this case pork, were fed and from which muscle of the animal the piece of meat you are eating has been cut, in order to get an approximate idea of how much of unquestionably health relevant micronutrients, such as coQ10, carnosine, anserine, taurine, creatine glutamine or haem you get - and in some cases the differences can be way larger than 100%!

If pizza salami equals pork...

... in epidemiological studies, how can these studies on the fallacies and advantages of eating red meat, which usually get a hell lo of media attention, be accurate, given the fact that the amount of unquestionably beneficial coQ10, for example, would differ by 60 percent, even if you would only ignore the difference between loin that was cut from the trapezius (= high coQ10 content) and the longissimus dorsi (=low coQ10 content)?

Figure 1: Content of selected amino acids and micronutrients in cuts from different muscle; data expressed relative to respective mean (total value is given in mg/100g above the bars) of all tested muscle samples (data based on previous studies by the co-authors that have been compiled for Reig. 2013).

Moreover, if you take a look at the complete data in figure 1 it should be clear that coQ10 is only one of several micro-nutrients / amino acids that are highly dependent on which muscle your particular steak or whatever you are about to eat was cut from. Let's take taurine as yet another example. A prolonged low dietary intake of taurine has been observed to be linked to a number of disorders including retinal degeneration, retardation of growth and development, cardiovascular dysfunctions, CNS abnormalities, immune impairment and hepatic disorders (Abebe. 2011). If you eat meat (fish & other animal products) only occasionally and are therefore at risk of not getting adequate taurine in your diet, eating sausages from a butcher you trust would be a better choice than a piece of ham, since the former do include the high taurine meat from the masseter (cheeks) of the animals, while ham does not.

Let's get to the obvious: Grass-fed is... ah, wait a minute

"Grass fed is best" as you will people say about beef obviously won't be the case for pork, because pigs, just like humans, by the way, are omnivores. The simple formula, grass-fed = most beneficial fatty acid and micronutrient profile that may (in general) be valid for beef doesn't apply and we will have to take a closer look at the actual data first to decide what would be the "best" feed for pigs, if the goal was not a maximal yield of lean meat (in that case adding some clenbuterol, like the Chinese like to do it would be the least you should do; cf. The China Post. 2011), but rather to produce the meat with the most beneficial fatty acid  composition.

Figure 2: Fatty acid composition (primary axis) and omega-6 to omega-3 ratio of pork from pigs fed different diets (corrected version of data Reig et al. re-pupublished based on previous studies; spec. the figure for the n6:n3 ratio in the "standard feed" group that's based on Enser et al. was off - a ratio of 1.54 is obviously unrealistic)

I we define "most healthy" as having the lowest omega-6 to omega-3 ratio - a practice that seems appropriate given that 95% of the inhabitants of the so-called 'Westernized World' consumes way too much of the former and (comparably) way too little of the latter type of polyunsaturated fatty acids, the data in figure 2 clearly argues in favor of *surprise* the standard feed - at least if you define that by the feed the animals the meat of which (50 samples) Enser et al. bought in British supermarkets in 1996 (note: these values are still higher than for the conventional beef samples from the same study, which had a n-6:n-3 ratio of ~2.2; cf. Enser. 1996). There are however more intricate patterns that are not evident from the overview in figure 2, but could have implications as far as the direction into which "pork production" could or should head to in the future is concerned (summarized based on Reig. 2013):

Do you notice a pattern? I guess even based on the data in figure 2 you will already have noticed that the "grainier" the diet, or in other words, the more corn and soy there is in the diet of the swine the less favorable is the fatty acid composition of their meats going to be. Now, I am asking an outrageous question: If swine are such a good model for human metabolism, what do you believe your belly was going to be made of, if you copied the pigs' diets and lived on "healthy grains", their oils and the uber-healthy soy beans for the (probably pretty short) rest of your life?
• more food (yet no excess) can produce overall leaner muscle meat in the type II fibers, while the total body fat is increasing
• aside from local desaturation and elongination effects, the overall muscular fatty acid pattern does (much like in humans, by the way) mirror the dietary intake
• canola or linseed oils produce a substantial increase in the content of linolenic acid (C 18:3), and slightly increase the eicosapentaenoic (EPA, C 22:5) and docosahexaenoic (DHA, C 22:6) acid contents in pork mea
• soy, peanut, corn, and sunflower increase the content of linoleic acid (C 18:2; omega-6), increase the n-6:n-3 ratio and reduce the content of mono-unsaturated fats (MUFAs)
• fish oils or algae added to the feed substantially increases the content of EPA and DHA and thus reduce the n-6:n-3 ratio
• a high saturated fat content as in tallow (see figure 2) increases the levels of palmitic, palmitoleic, stearic and oleic acids in pork meat and reduces the PUFA:SFA ratio 
• CLA supplementation can increase the CLA content of the fatty portion of the meats (1% CLA results in 5.5 mg CLA/100g) and the adipose tissue (2% CLA yields 1,490mg CLA/100g fatty acids).

As you can see, the same rule applies for humans, pigs and, as you know from a previous SuppVersity post, mice who are fed inferior, since soy-fed salmon, as well: You are what you eat, folks!

Wallowing, roaming, routing: Work out like a pig

Since pigs make a pretty decent model of human metabolism and in view of the fact that - aside from our diets - the amount of exercise we get is one of the fundamental determinants of the total and relative levels of body fat, it should not be forgotten that "exercise" or rather the ability to range freely and be as active as any swine should be, is another determinant of the quality of the meat you are buying at the supermarket, grocery store, butcher or your local farmer. In this context, Reig et al. point out that

If you have no idea of the different cuts and location of the individual muscle, I suggest you download the "Meat Cuts Manual" from the website of the Canadian Food Agency. It's free and bilingual.

"[i]t has been reported that pigs maintained in free-range conditions in the Mediterranean forest had subcutaneous and intramuscular fats with higher monounsaturated fatty acids and lower saturated fatty acids than those pigs housed individually and receiving acorns as feed. The subcutaneous fat depth increases with exercise being 15.9 mm for exercised pigs in comparison to 11.5 mm depth for those kept in confinement. The same applies for the intramuscular fat content where 3.36% for extensive vs 1.44% for intensive raised pigs have been reported in the semimembranosus muscle." (Reig. 2013)

And if you really intend to overcomplicate things, you would also have to ask your butcher, whether the sausages you are about to buy were made of the meat of male of female pigs. After all, meat from barrows typically contain more fat and marbling and a thicker subcutaneous fat layer than meat from gilts (Armero. 1999). But let's face it: If you start stressing about things like this, the quality of your meat is probably your least problem.

If you want to know read more about epidemiological overgeneralization andthe effects of "pork" and red meat on your health (spec. the prostate) I suggest you go back to the Meat-Ology post.

So what's the bottom line, then: I guess the bottom line of the above insides is twofold. As far as you as an individual are concerned, it would be yet another argument for getting your meats (pork or whatever else) from a farm nearby, where you know what you are getting. It is yet also evidence of the fact that meticulous nutrient counting as I often see it in former calorie counters who have nor grasped the notion that "a calorie is not a calorie" is of little avail - at least if you expect to be able to calculate them as precisely as you can read them on the nutrition labels of the 90% artificial and 100% standardized convenient foods that's probably much more the answer to the question "Why are we fat?" than the non-descript statement "insulin".

In fact, the real significance of these results lies elsewhere. It concerns the way epidemiological studies are conducted (I may remind you of the metaphorical pizza salami being red meat or pork), their over-generalizing interpretations and the conclusions on what the optimal human diet should look like. So, once the next study is telling you "red meat" or "pork" is bad for you - you may want to remind yourself of some of the things you have learned in today's blogpost and ask yourself (and if you incidentally have the chance, the researchers as well): What kind of "pork" are we talking about?

References:

• Abebe W, Mozaffari MS. Role of taurine in the vasculature: an overview of experimental and human studies. Am J Cardiovasc Dis. 2011;1(3):293-311.
• Armero E,  Flores M,  Toldrá F,  Barbosa JA,  Olivet J,  Pla M,  Baselga M.Effects of pig sire types and sex on carcass traits, meat quality and sensory quality of dry-cured ham.  Journal of the  Science of  Food  and  Agriculture. 1999; 79:1147-1154.
• Enser M, Hallett K, Hewitt B, Fursey GA, Wood JD. Fatty acid content and composition of english beef, lamb and pork at retail. Meat Sci. 1996 Apr;42(4):443-56.
• Reig M, Aristoy MC, Toldra.Variability in the contents of pork meat nutrients and how it may affect food composition databases. Food Chemistry. 2013 [ahead of print]
• The China Post. Clenbuterol-tainted pork latest China food scandal. March 18, 2011. < http://www.chinapost.com.tw/china/national-news/2011/03/18/295146/Clenbuterol-tainted-pork.htm > retrieved Dec 06, 2013.

Chromium Picolinate Worsens Insulin Sensitivity in Healthy, Non-Diabetic, Non-Obese Individuals by Up to 25%

The more supplements you take the more likely you are to get way more than the 200mcg of chromium of which previous studies have shown that they are useless for healthy people, but at least not detrimental (cf. Lukaski 1996 & 2007; Vincent. 2007). Especially people who like the  'poly-supplementary' approach are yet at risk of getting so much of a this trace mineral that it will hamper not improve their insulin sensitivity.

I don't have to tell you that you would already be dead if you were following all the bro-scientific advice that's out there on the Internet and still I usually recognize a certain reluctance to give up on what X suggests and Y has tried an what has worked so well for Z. One of the instances, where I have hitherto been missing a 100% convincing argument to argue that this is just another instance where common wisdom would in fact be better called "common stupidity" is the "insulin mimetic" or "insulin sensitizer" (or whatever your favorite bro-expert may call it) chromium picolinate. With the recent publication of the result of a study on the effects of chromium supplementation in healthy individuals there is now finally a human study that confirms that chromium, which has never been an "insulin sensitizer", but rather an "insulin release amplifier" that reduced blood glucose in diabetics by simply having them produce even more insulin is not a supplement any healthy man or woman, let alone athlete should consider a staple of his or her regimen.

The long and short: Chromium hampers insulin sensitivity in normoglycemic individuals

For their experiment lead author Umesh Masharani and his colleagues from the UCSA recruited a group of 27 non-obese, non-diabetic, healthy subjects between the ages of 20 and 50 with a body mass index of less than 27 kg/m² and <24 kg/m² for subjects with Asian heritage (the cut-off limits were set so that they would be below a BMI that has not yet been shown to be an independent risk factor for insulin resistance; cf. Clausen. 1996; Newell-Morris. 1998).

To evaluate whether chromium picolinate (ChrPic) supplements, which contributed with $150,000,000 to the revenue of the supplement industry in 1996 (Nielsen. 1996), could come up to the claims that they would exert beneficial effects on glucose tolerance and insulin sensitivity, the study participants were randomized to take either a placebo or a high dose 500µg CrPic supplement twice daily for 4 months (the dosage was selected in view of previews studies reporting greater benefits of 1,000 vs. 200mcg of CrPic in - you already guessed it - diabetic subjects; cf. Morris. 2000).

Figure 1: Insulin sensitivity measured by euglycemic clamp before and after the 16 week intervention (left); change in insulin sensitivity of the individual subjects plotted against serum chromium levels at the end of the study (Masharani. 2013)

As the data in figure 1 goes to show, the results of the CrPic intervention were more or less the exact opposite of what the ~10 million US consumers of respective supplements probably expect from the pills many of them are taking almost religiously. Despite the fact that all subjects had very low chromium levels at the beginning of the study, the previously non-significant minimally benificial relation between both serum and urinary chromium, on the one hand, and insulin sensitivity (r = 0.24, p=0.1; r=0.08, p=0.79 respectively), on the other hand, had turned into a very significant negative correlation between high(er) urinary and serum chromium concentrations and lower insulin sensitivity at the end of the 16 week intervention period (figure 1, right).

"Due to the apparent variation in the degree of chromium absorption between subjects, we examined the relationship between serum chromium and change in insulin resistance. After controlling for baseline patient characteristics, results of a multiple regression analysis showed a strong association between serum chromium and worsening of insulin–mediated glucose disposal (β= -0.83, p<0.01), where subjects with the highest serum chromium had a decline in their insulin sensitivity. To further explore the association between chromium absorption and insulin resistance, patients within the chromium group were divided (based on  a medial split at 3.10 µg/L) into a high (n=6) and low (n=8) serum chromium group [...] There were no group differences at baseline; however, at post-assessment participants in the high serum chromium group (> 3.1  µg/L) were more insulin resistant than participants in the low serum chromium group (≤3.1  µg/L) or the placebo group (p=0.02, p=0.05 respectively) (Figure 3)." (my emphases in Masharani. 2013)

Due to the fact that the scientists did not observe any differences between the placebo and low serum  chromium groups (on a side note, contrary to many other studies insulin Masharani et al. measured the insulin sensitivity in a very reliable way with an euglycemic hyperinsulinemic clamp; cf. Defronzo. 1979), the scientists also conducted a post-hoc analysis to identify potential confounding factors that may have influenced the outcome of the trial. Neither changes in triglycerides levels LDL, BMI, or truncal fat were yet associated with the differences they observed between the supplemented and non-supplemented participants. Interactions that would reduce the significance of the observed correlations were likewise absent:

"Furthermore, when changes in triglycerides, LDL, BMI, and truncal fat were individually added to the model, none were independent significant predictors of change in insulin sensitivity, and chromium absorption remained a significant predictor of reduced insulin sensitivity in each model." (Masharani. 2013)

Against that background the scientists conclude that there must be a "direct effect of chromium on changes in insulin action". A mechanism, by the way, which is totally independent of classic markers of insulin resistance such as high serum lipids and abdominal / truncal adiposity .

Being healthy is a good predictor of increased chromium absorption and more pronounced negative effects, so if you are healthy and want to stay this way don't even think of taking high dose chromium supplements.

Despite the fact that the changes in insulin resistance did not depend on changes in serum lipids and other markers of metabolic health, Masharani and his colleagues were able to show that the increase in chromium levels in response to supplementation did. With the already mentioned statistically significant correlation between increases in serum chromium levels (higher response to supplementation = higher increase), on the one hand, and the worsening of insulin sensitivity, on the other hand, this means that the healthiest subjects, namely ...

"[...] subjects with lower triglycerides, and those with lower levels of homocysteine [who had] a greater likelihood of being in the high absorption group" (Masharani. 2013)

... were at the same time those who were at the greatest risk of the ill side-effects high dose chromium supplements exert on the insulin tolerance of healthy, non-diabetic, normal-weight individuals.

No matter if it may have helped you produce insulin back in your obese days, once you have accomplished this you better avoid high dose or multiple (hidden) sources of supplemental chromium like a plague - unless you can't afford new jeans, of course ;-)

Bottom line: Unless you are not a type II diabetic or feel the urgent desire to become one, you better steer clear of exuberant amounts of supplemental chromium the RDA is enough. This is particularly true, if you are already taking a multi (which is almost guaranteed to have 200mcg in it), or any BB-style supplements. After all, "broscience" wants it that chromium is in everything that's even remotely related to insulin / nutrient uptake or whatever. With the use of only one of these products and 200mcg of supplemental dietary chromium per day, you may still argue that it probably won't do much harm. When you add another 200mcg from your "nutrient partitioner" on top of the 200mcg you get from your multi and the 200mcg of which you probably did not even realize yet that they are part of your pre-workout supplement, however, you can hardly complain about simply not being able to tolerate carbohydrates - I mean, what's your body supposed to do if you are dumb enough to believe in the promises of fat loss and lean mass increases that have been debunked in the late 1990s, already (cf. Lukaski 1996 & 2007; Vincent. 2007), and simply chose to ignore the latest scientific evidence that chromium picolinate supplements are not just useless, but actually detrimental to your health?


References:

• Clausen JO, Borch-Johnsen K, Ibsen H, Bergman RN, Hougaard P, Winther K, Pedersen O. Insulin sensitivity index, acute insulin response, and glucose effectiveness in a population-based sample of 380 young healthy Caucasians. Analysis of  the impact of gender, body fat, physical fitness, and life-style factors.  J Clin Invest. 1996;  98(5):1195– 1209.
• Defronzo RA, Tobin JD, Andres R. Glucose clamp technique: a method for quantifying insulin secretion and resistance. Am J Physiol. 1979; 237:E214–E223. 
• Lukaski HC, Bolonchuk WW, Siders WA, Milne DB. Chromium supplementation and resistance training: effects on body composition, strength, and trace element status of men. Am J Clin Nutr. 1996 Jun;63(6):954-65.
• Lukaski HC, Siders WA, Penland JG.  Chromium picolinate supplementation in women: effects on body weight, composition, and iron status. Nutrition. 2007; 23(3):187– 195.
• Masharani U, Gjerde C, McCoy S, Maddux BA, Hessler D, Goldfine ID, Youngren JF. Chromium supplementation in non-obese non-diabetic subjects is associated with a decline in insulin sensitivity. BMC Endocr Disord. 2013 Nov 30;12(1):31.
• Morris BW, Kouta S, Robinson R, MacNeil S, Heller S. Chromium supplementation improves insulin resistance in patients with Type 2 diabetes mellitus.  DiabetMed. 2000; 17(9):684–685.
• Newell-Morris LL, Treder RP, Shuman WP, Fujimoto WY. Fatness, fat distribution, and glucose tolerance in second-generation Japanese-American (Nisei) men. Am J Clin Nutr. 1989; 50(1):9–18.
• Nielsen FH. Controversial Chromium: Does the superstar minearal of the mountebanks receive appropriate attention from clinicians and nutritionists?  Nutr Today. 1996; 31(6):226–233.
• Vincent JB: The nutritional biochemistry of chromium (III). Amsterdam, Boston: Elsevier. 2007.

Magic Numbers: 1g Protein per 2g Carbs + Circuit Training = The #1 Formula for Weight & Fat Loss in Obese Women?

If there is one thing about this study that's not debatable it is that eating whole foods, cleaning your diet from all sorts of junk and working out lifting weights and doing aerobics were the cornerstones of the weight loss success of these women, regardless of whether they consumed a low, medium or high amount of protein.

Roughly two years ago, when the SuppVersity opened its doors, it was pretty rare to find a scientist who would be willing to "waste" (that's probably how he or she would have said it ;-) precious time and the limited funds of his institution to study the effects of "high protein diets". Over the past couple of months, things have been changing, though: I've just checked and according to Pubmed, the number of publications containing the exact phrase "high protein diet", alone,  has increased by ~32% in 2011 and has remained on the same comparably high level ever since. That said a recent study from the University of Guelph in Canada is only the latest in the line of a whole host of publications that deal with the beneficial effects of high(er) protein diets on weight loss in overweight, (pre-)diabetic subjects; exactly those people who have previously been advised to stay clear of all fats, ignore the proteins and focus on the "healthy and satieting" low GI carbs, by the way.

Yet though the tides may be turning ...

... a paradigm shift within the scientific community usually doesn't come over night - a famous scientist and philosopher of science once said that it usually takes until the proponents of the old paradigm died out, before a new one is fully established. Since roughly two years and even two decades are hardly enough for this to happen, it is actually not surprising that Dawn. D. Campbell and Kelly A. Meckling, despite giving the high protein diet credit for having produced some promising results in the past, speculate that

"the combined effects of a normal protein: carbohydrate ratio with cardiovascular and resistance training would be more beneficial and easier to comply with than either the low- or high-protein diets in this target population of women with risk factors for the MetS" (Campbell. 2013)

In view of the fact that Rehm et al. conclude ther 2008 review of the literature with the statement...

"Diets moderately increased in protein and modestly restricted in carbohydrate and fat, particularly saturated fat, may have beneficial effects on body weight, body composition, and associated metabolic parameters." (Rehm. 2008)

... and against the background that the evidence of the real-world benefits of a higher protein intake is accumulating, and pertinent reviews and editorials have been appearing on a monthly basis, ever since (e.g. Hession. 2009; Keller. 2011; Acheson. 2013), the research hypothesis of the study at hand sounds a bit 'last year', not to say 'last decade' to me.

Do we have a bias here?

Moroever, with the research hypothesis being a good indicator of a built-in bias, we will have to pay pretty close attention to distinguish the actual data Campbell and Meckling measured from their interpretations of the latter. After all, every "good" SuppVersity student should remember that we have seen time and again how the differences between facts and interpretations often become somewhat blurry in the conclusions of way too many (for my liking) papers as of late. So let's see if Campbell's and Meckling's conclusion that...

"A diet with a 1:2 protein:carbohydrate ratio promoted better improvements than either the LP or HP diets, and may be superior in reducing long-term chronic disease risk in this population." (my emphasis in Campbell. 2013)

What can be said right away is that the protocol the scientists used, specifically the way they are working with macronutrient ratios instead of paradigmatic percentages of the RDA, is actually pretty progressive.

"Subjects were encouraged to consume whole foods as opposed to pre-packaged or processed foods and to restrict intake of whole-fat dairy, high-fat red meats, deep-fried foods, potato chips, cookies and refined sugar products. Instead, subjects were encouraged to choose whole-grain pro-ducts, lower-fat meats, fish, turkey, eggs, low-fat milk and cot-tage cheese, nuts, seeds, and a variety of vegetables, fruits and berries. Before beginning the study workout programme, subjects completed baseline fitness testing to assess muscular strength and cardiovascular fitness." (Campbell. 2013)

Instead of simply upping the protein intake from the 0.8g/kg body weight the RDA suggest would be optimal, Campbell and Meckling put their obese (mean BMI ~35kg/m²) female participants (of which only 54 completed the study) on calorically restricted diets (supposedly -30% below their habitual energy intake which had been evaluated by the means of a 7-day food record) which contained an equal relative amount of fat (<30%), but had different protein-to-carbohydrate ratios:

• low protein (LP) - 1g protein : 4g carbohydrates
• medium protein (MP) - 1g protein : 2g carbohydrates
• high protein (HP) - 1g protein : 1g carbohydrates

To put that in perspectve, a women who may have been consuming a baseline diet containing 2,300kcal per day would have had to restrict her caloric intake to 1,610kcal. Of these 1,610kcal, <30% would come from fat (60g), while the rest would be ingested in the form either 56g protein and 225g carbohydrates (LP), 94g protein and 188g carbohydrates (MP), or 140g protein and 140g carbs (HP).

There is no effective weight loss without exercise and a whole food diet!

In addition to the dietary regimen the 117 participants who initially met the eligibility criteria were supposed to particpate in a  supervised 12-week circuit training program at the University of Guelph Athletic Centre.

The 1 h study fitness programme was completed three times/week on Mondays, Wednesdays and Fridays at a consistent time assigned to each subject. Subjects had to sign in for their workout sessions, and all exercises were supervised by a study coordinator and/or personal trainer. Subjects began their workout with a 9 min warm-up using springboard pads where walking in place, jogging or dancing took place. Then, subjects completed a 30 min circuit alternat-ing between resistance training and cardiovascular exercise bouts. All main muscle groups of the body were targeted throughout the thirteen resistance training machines. Starting weight values on resistance training equipment were 65 % of their calculated maximum strength as determined by their modified 1 repetition maximum. Subjects were instructed to complete one set of eight to fifteen repetitions on each piece of equipment to reach muscle fatigue."

The circuit training used a build-in progression with ~5% increases in weight, whenever the subject were able to complete 15 repetitions on a given exercise. The same goes for the aerobic parts of the workouts, where the

Subjects began exercising at 65 % of their maximum heart rate for the first 3 weeks and gradually increased the intensity by 5 % every 3 weeks to a maximum intensity of 80 % by week 12. 

As far as the aerobic part of the workouts was concerned, they alternated between a step, springboard pad and stationary bike. All workouts closed with some ab training (including a standard crunch, oblique crunch and a core-strengthening exercise called the plank, done to failure) and stretching.

"Hey, exercise is good for me!"

Other than you may have expected the 35 dropouts (which were equally distributed across all dietary groups) were not brought about by laziness or the unwillingness to get up and move. On the contrary, many subjects recorded that they had "more energy and felt better than before the study began" (Campbell. 2013). Aside from minor constipation (the scientists don't mention in which group this occured) and some minor shedding in one of the subjects in the low protein group (probably coincidence, by the way), the intervention went fine for those who had the guts, time and discipline to stick it and yielded - as the data in figure 1 goes to show - favorable results in all three arms off the study:

Figure 1: Changes in antroprometric data, blood pressure and heart rate after 12 weeks (based on Campbell. 2013)

If we were stupid enough to focus solely on the BMI reductions, we could even say that all diets were equally effective. Upon closer scrutiny and the use of some statistical shenanigan, it does however become clear that the scientists' initial hypothesis that the normal protein diet with a 1:2 protein to carbohydrate would have a small edge over both, the low protein diet (in terms of body fat loss and lean mass retention; p < 0.05) and the high protein diet (solely in terms of body fat loss; p < 0.05) seems to hold true. What's more, this trend in DXA measured improvements in body composition stands in line with noteworthy reductions in waist circumference (7.9, 11.6 and 8.6 cm in the LP, NP and HP), of which Cambell and Meckling write:

"Again, the decrease in the NP group was greater than that in the LP group. Further-more, hip circumferences decreased similarly (P < 0·05) in response to each diet with reductions of 7·4, 8·8 and 8·4 cm in the LP, NP and HP groups, respectively. Waist:hip ratios declined significantly (P < 0·05) after 12 weeks by 0·01, 0·04 and 0·01 in the LP, NP and HP groups, respectively, but reductions were greater in the NP v. LP (P=0·020) and HP (P=0·025) groups." (Cambell. 2013)

No group specific diet effects were observed for the reductions in blood pressure and heart rate. Now, this obviously raises the question, whether the existent changes may have been brought about by non-compliance.

"So maybe the protein eaters just didn't eat their protein?"

Non-compliance is, as SuppVersity students know, one of the major problems with all of these relatively uncontrolled dietary interventions (see "High Carb vs. High Fat: What Really Happens When Science Meets the Real World"). And in fact, with average caloric intakes of 3641, 3729 and 3633 kJ/d  in in the low, medium and high protein groups, the subjects were actually consuming 10% less energy than they were supposed to.

Suggested read for everyone who can't or doesn't want to believe that you can easily eat 157g of carbs (which is what the women in the normal protein group did) and still lose fat while retaining all your precious lean muscle mass: "Carbohydrate Shortage in Paleo Land: New Data for A Scientific Outlook at the Low-to-No Carb Paleo Confusion. Will More Than 125g of Carbs Make You Fat?" (read more)

Despite the fact that this type of non- or rather 'over-compliance' can also have detrimental effects on someone's weight loss efforts, there were no intergroup differences which would skew the ultimate comparison; and much to my surprise the majority of the subjects did even manage to come close to their macronutrient goals by adapting their previously almost identical protein to carbohydrate ratios of  1:3.5, 1:3.2 and 1:32 at baseline to 1:3.5, 1:2.1 and 1:1.3 by week 12. With respect to the total protein intake, this equals

• significant decreases in protein intake (82 and 88 g/d to 55 and 75 g/d) for the low and normal protein groups and
• significant increases in protein intake (from 84 to 100 g/d) in the high protein group

This does also mean that the percentage of subjects who met the 0.8g/kg RDA for dietary protein intake at the beginning of the study had dropped to zero in the low protein group by week 12.

The subjects in the normal protein intake group were about as close as you can get and those in the high protein group consumed significantly more protein than the 'well-meaning' authors of the dietary recommendations feel would be good for them ;-) Other changes the scientists observed were:

• a significant declines in carbohydrate intake in the normal and high protein group
• a decreased sugar intake in all groups (most pronounced in the HP group)
• a decreased fat intake in all groups (p<0.001)
• significant decreases in sodium intake in all groups 
• non-significant decreases in calcium, zinc and vitamin D intake

I guess, I don't have to tell you that none of the few existing inter-group differences discussed above appears to provide any reason to question the small, but statistically significant superiority of the normal protein diets compared to either the low protein or the high protein diets. And despite being the only study participants who were in a positive nitrogen balance, the subjects in the HP group did not see more beneficial effects on the retention of lean mass than the normal protein group.

So what?! Normal protein rules?

No matter how you look at the results of the study at hand, based solely on the data Campbell and  Meckling presented here, there is not a single argument to brought forward in favor of the 1:1 vs. the 1:2 protein to carbohydrate ratio. Moreover, the single most important determinant of (long-term) dietary success that is the ease with which dieters feel they can adhere to a given nutritional protocol also speaks in favor of the normal, not the high protein diet. The answer to the initially raised question, whether the scientists' conclusion that.. 

"[a] diet with a 1:2 protein:carbohydrate ratio promoted better improvements than either the LP or HP diets, and may be superior in reducing long-term chronic disease risk in this population" (my emphasis in Campbell. 2013)

...was biased by their own research hypothesis would therefore be "NO! It wasn't." -  Now, that does not change the fact that I personally am biased and would therefore have liked the ladies to get past the 90g of quality protein / day margin. This would incidentally not have been difficult, if these wannabe overachievers had not reduced their caloric intake from ~2,300kcal/day to ~1,360kcal, but had contended themselves with the planned -30% reduction. The difference of 230kcal/day would left more than enough room for two additional protein shakes per day!

Figure 2: Fat loss and lean mass gains of the police officers in the Demling study (Demling. 2000)

That a similar regimen consisting of an even milder -20% reduction in calorie intake and the consumption of 70-75g of whey or casein hydrolysate can produce magnificent results, when it is combined with regular strength training (4days per week 30-35min of liftin), has been shown by Demling and DeSanti 12 years ago, already (see figure 2).

It should be said, though that the 'success ratio' of carbs to protein in the Demling study was likewise ~1:2 (!) - the sole difference was that the obese police officers in the Demling study simply ate twice as much protein and twice as much carbs with a baseline fat intake of ~35g per day.

References:

• Acheson KJ. Higher-protein diets for health? European Journal of Clinical Nutrition. 2013; 66, 763–764.
• Brehm BJ, D'Alessio DA. Benefits of high-protein weight loss diets: enough evidence for practice? Curr Opin Endocrinol Diabetes Obes. 2008 Oct;15(5):416-21. 
• Campbell DD, Meckling KA. Effect of the protein:carbohydrate ratio in hypoenergetic diets on metabolic syndrome risk factors in exercising overweight and obese women. Br J Nutr. 2013 Nov;108(9):1658-71. 
• Demling RH, DeSanti L. Effect of a hypocaloric diet, increased protein intake and resistance training on lean mass gains and fat mass loss in overweight police officers. Ann Nutr Metab. 2000;44(1):21-9.
• Hession M, Rolland C, Kulkarni U, Wise A, Broom J. Systematic review of randomized controlled trials of low-carbohydrate vs. low-fat/low-calorie diets in the management of obesity and its comorbidities. Obes Rev. 2009 Jan;10(1):36-50.
• Keller U. Dietary proteins in obesity and in diabetes. Int J Vitam Nutr Res. 2011 Mar;81(2-3):125-33.

Pigs Would Pick MSG - Glutamate Seals the Gut, Decreases Liver & Muscle Fat & Increases Plasma Amino Acids in Swine

Piglets would buy MSG food ;-)

Mono-sodium glutamate (MSG) and the "Chinese restaurant syndrome", obesity and overeating are often thrown together into a single psedo-scientific crock pot with the result being a brew that's 50% hear-say, 40% fear and 10% science. The study we are going to look at today is unquestionably part of the latter ingredient and its results do stand in line with my previously stated concern "that MSG is one of those substances that is usually found in foods with a whole host of other nutrient-poor ingredients, anti-nutrients and proven obesogenic, pro-inflammatory and otherwise unhealthy substances and food additives" ("MSG, NFALD, Leaky Gut & Brain ...") and could thus rather be corollary to, than causative of the toll the fast, convenient and nutrient deficient foods in the Western diet are taking on our health.

Published ahead of print in the online version of the journal Amino Acids you will find a study by a group of researchers from the Texas A&M University. The study was, according to the authors intended to "fill [the] important gap of knowledge about glutamate nutrition and metabolism in animals" (Rezaei. 2013). Luckily their study subjects were pigs, allegedly young pigs, but still omnivores like us and one of the best models of the human digestive tract we have:

"Both humans and pigs are highly dependent on dietary quality since symbiotic microorganisms within the gut play a relatively minor role in modifying the nutrients that are ingested. Intestinal  transit times and digestive efficiencies are comparable. Postabsorptive metabolism is also similar in many respects, although the wide differences in length of gestation and the numbers of young born introduce a potentially significant divergence in nutrient needs for reproduction. [...] Nevertheless, when minimum nutrient requirements of swine and established recommended daily allow­ ances of humans are expressed per kilogram of dietary dry matter (assuming an intake of 500 to 800 g of dry matter per day by teenagers and adults), these values are highly related. It is only reasonable that one not draw unsupport­able inferences from one species to another, but with the possible exception of nonhuman primates, it is apparent that the omnivorous pig is one of the best models for study of nutrition issues in the omnivorous human." (Miller. 1987)

Against that background it is quite intriguing that Rezaei. et al. did not find any of the suspected negative side effects of MSG up to a dosage of 4% in the diet of their piglets.

Figure 1: Weight development and feed intake and effciacy in pigs on diet containing different amounts of supplemental MSG (data based on Rezaei. 2013)

In fact, instead of eating more, the pigs that received the MSG-supplemented diets consumed slightly, but significantly less food than their peers. Despite these appetite suppressing effects of the diet, the piglets in the high MSG arm of the study still gained the most body weight and thusly had the 'optimal' (for lovers of Chines restaurant probably rather 'most detrimental') gain:feed ratio.

The amino acid modifying effects of MSG

When we are seaching for the underlying reasons of these changes, it may be worth taking a look at the amino acid composition of the plasma of the piglets after 21 days on diets supplemented with different amounts of MSG at 1 and 4 h after feeding. During this prostprandial phase, the scientists observed

• 

  More about MSG in human health

  significant increases  in aspartate, glutamate, glutamine, histidine, citrulline, arginine, taurine, alanine, methionine, valine, phenylalanine, isoleucine, leucine, proline, cysteine, ornithine, and lysine in plasma at both time points, i.e. one and four hours after feedin,
• highly significant increases in asparagine, serine, threonine, tryptophan, and tyrosine 1h after feeding and
• significant increases in alanine, citrulline, glutamate, methionine, ornithine, phenylalanine, proline, and tryptophan in the first hour of the postprandial window

If we also take into account previous rodent studies which have shown that MSG reduces the deposition of fatty acids in white adipose tissue (Kondoh. 2008), it cannot be ruled out though that these increases in weight gain were related to increases in lean- not fat tissue (remember: muscle is heavier than fat); after all we are dealing with growing young pigs, in which you would expect an increase in essential and non essential amino acid availability to help with skeletal muscle metabolism (Mahan. 1998).

Figure 2: Total lipid content in percent of control in response to MSG feeding at different doses (left) and the modulatory effects of sodium intake (NaCl) on the effects of MSG (right; data based on Rezaei. 2013)

As the data in figure 2 goes to show this hypothesis appears to stand in line with the decreased fatty acid deposition in liver and skeletal muscle, which will at the same time prevent negative side effects of intra-hepatic and -skeletal lipid accumulation on liver and muscle glucose uptake.

Does salt modify the effects of MSG? And what's the role of the gut in all this?

Against that background it is actually a pitty that we don't have data on the fatty acid content of liver and muscle tissue in response to the different levels of dietary salt in the diets (figure 2, right). I mean, at first sight it appears that more salt could 'ameliorate' the detrimental effects of MSG feeding on the body weight of the rodents, but if the latter was not detrimental, but beneficial, this would certainly entail the question if it's not MSG per se, but rather it's co-appearance with too much, or due to it's ability to boost all taste perception to little sodium in the previously mentioned fast, convenient and nutrient deficient foods, way too many people have gotten addicted to.

You see, just as so many times before things are way more complex than they may seem at first sight and if the interactions of body weight, lean mass, intrahepatic and intramuscular lipids and dietary salt with MSG was not already enough, the data in figure 3 brings another (side?) effect into play the importance of which must not be underestimated - the effect of MSG on the intestinal morphology of the pigs:

Figure 3: Jejunal morphology and jejunal concentrations of DNA, RNA, protein, ATP, and glutathione in 28-day-old pigs weaned at 21 days of age (Rezaei. 2013)

I don't know if you remember the side effect of the chronic ingestion of zinc on the intestinal structure of rodents that caused quite a stir in the zinc-loving bodybuilding community back in June!? In essence, the effects of mono-sodium glutamate on the microvilli, which are responsible for the absorption of nutrients look very similar to the ones that were observed by Taneja et al.in response to Zinc supplementation (SuppVersity: June 13, 2013). As previously mentioned this is per se not a bad thing and could in fact come very hand to people with chronic inflammatory conditions suffering from a "leaky gut" or people who want to protect their gut from the side effects of the chronic use of NSAIDs, where MSG has only recently been implicated as a viable tool to prevent and heal mucosal damage (Amagas. 2013).

Figure 4: Postprandial glucose levels (left) and intestinal morphology (right) of mice on diets with different concentrations of mono-sodium glutamate (Rezaei. 2013)

As figure 4 goes to show this could actually work with MSG without the zinc-induced increases in insulin and blood glucose (see figure 2 in previous article). Whether these effects are directly related to the ingestion of MSG or its glutamin-sparing effects n the gut cannot be said for sure, though:

"Grant alert" Despite the fact that I am pretty sure that the actuall data in this study is accurately reported, I still want to point out that the scientists received "a grant from the International Glutamate Technical Committee". It's explicitly listed in the "acknowledgments" and probably not much of an issue outside of the discussion in which you will obviously miss references to potential negative side effects (which have not been observed in the study, though).

"Thus, dietary supplementation with glutamate may enhance the availability of dietary glutamine in plasma. As a versatile amino acid, glutamate participates in both synthetic and oxidative pathways in the small intestine, resulting in the production of proteins, ornithine, citrulline, proline, arginine, alanine, aspartate, glutathione, CO2, and ATP. Therefore, dietary supplementation with glutamate increased the plasma concentrations of these amino acids  and jejunal concentrations of glutathione in weaned pigs. Compelling evidence shows that dietary glutamate is a major energy substrate for the small intestine, which is an organ with a particularly high met- abolic rate. In support of this notion, we found that dietary MSG supplementation increased jejunal concentrations of ATP in weaned pigs. Additionally, glutamate is an excitatory neurotransmitter, thereby regulating the motility of the gastrointestinal tract. Thus, when a weaning diet is deficient in glutamate, gut atrophy occurs and the efficiency of utilization of dietary protein for growth and other physiological functions is greatly decreased." (Rezaei. 2013)

As evidence from previous studies by Kondoh et al. suggests, the effects of glutamate do not end at the intestinal brush border. Its centrally mediated downstream effects after interacting with l-Glutamate receptors in the intestines are however still not fully understood and could either be beneficial (as the work by Kondoh et al. would suggest; Kondoh. 2008 & 2009), be without physiological consequences or - as the mainstream myth suggests - "be the devil"; with the latter being much more likely in people with genetic or already established metabolic problems which result in a deficiency of glutamate dehydrogenase (Stanley. 2009).

Bottom line: The last mentioned problems certain individuals who have inherited or acquired problems with the enzymatic conversion of glutamate are yet not the only reason why I strongly caution against taking the results of the study at hand as a free ticket for limitless MSG consumption. If it's not the MSG that's going to make you fat, I can assure you that those 'foods' in which it is used will be getting the job done pretty quickly and will thus compensate for any possibly existent improvements in intestinal and whole body amino acid metabolism.

Parmigiano Reggiano aside from seaweed the #1 "real food" offender in terms of MSG and still good for your bones (Pampaloni. 2011) - one of many examples of the fallacy of black-and-white thinking. To heal your gut, glutamine would yet still be your better choice, I suppose ;-)

That said, there are still unresolved issues related to the negative effects of MSG on the immune system and the thymus. The dosages that are required to observe toxic effects may be hilarious if you take into account how much of it you find in an individual food item, and even if you started supplementing with MSG, or lived on fast- and convenient food, only, you will probably be hard pressed to get up to the 50g+ human equivalent of mono-sodium glutamate which was sufficient to significantly decrease thymus cell viability in rats (Pavlovic. 2009). In case you feel you are endangered and belong to the people who rather wear a helmet than stop hammering their head against a wall, you could try to counter that with an additional 6-7g of vitamin C (for the rodents that worked)... but let's be honest, wouldn't your life be much easier, if you simply stuck to whole foods and don't worry about the occasional piece of aged Parmesan cheese with 1680 mg glutamate per 100g. It could not just be good for your gut, but has been shown to be good for your bones (Pampaloni. 2011), probably not because, but at least despite the high MSG content.

References:

• Amagase K, Ochi A, Kojo A, Mizunoe A, Taue M, Kinoshita N, Nakamura E, Takeuchi K. New therapeutic strategy for amino acid medicine: prophylactic and healing promoting effect of monosodium glutamate against NSAID-induced enteropathy. J Pharmacol Sci. 2013;118(2):131-7.
• Kondoh T, Torii K (2008) MSG intake suppresses weight gain, fat deposition, and plasma leptin levels in male Sprague-Dawley rats. Physiol Behav 95:135–144.
• Kondoh T, Mallick HN, Torii K. Activation of the gut-brain axis by dietary glutamate and physiologic significance in energy homeostasis. Am J Clin Nutr. 2009 Sep;90(3):832S-837S.
• Mahan DC, Shields RG Jr. Essential and nonessential amino acid composition of pigs from birth to 145 kilograms of body weight, and comparison to other studies. J Anim Sci. 1998 Feb;76(2):513-21.
• Miller ER, Ullrey DE. The pig as a model for human nutrition. Annu Rev Nutr. 1987;7:361-82. 
• Pampaloni B, Bartolini E, Brandi ML. Parmigiano Reggiano cheese and bone health. Clin Cases Miner Bone Metab. 2011 Sep;8(3):33-6.
• Pavlovic V, Pavlovic D, Kocic G, Sokolovic D, Sarac M, Jovic Z. Ascorbic acid modulates monosodium glutamate induced cytotoxicity in rat thymus. Bratisl Lek Listy. 2009;110(4):205-9.
• Stanley CA. Regulation of glutamate metabolism and insulin secretion by glutamate dehydrogenase in hypoglycemic children. Am J Clin Nutr. 2009 Sep;90(3):862S-866S.
• Rezaei R, Knabe DA, Tekwe CD, Dahanayaka S, Ficken MD, Fielder SE, Eide SJ, Lovering SL, Wu G. Dietary supplementation with monosodium glutamate is safe and improves growth performance in postweaning pigs. Amino Acids. 2013 Nov 2.