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.

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.

The Female(?) Athlete Triad - Part III/III: Road to Recovery! Step #2 = Accept There is No Magic Macronutrient Ratio

No need to raid another tomb, Lara, the quest for the one and only ideal macronutrient composition that will yield optimal results for the rest of your life ends here (img courtesy of Paramount)!

I am not planning to bore you with a longish summary of the previous installment(s) of this series, here. Still, I don't want to head on to the 2nd step of the "Road to Recovery", which is going to deal with the quest for the "optimal" macronutrient ratio, without a brief reminder of the central role of nutrient availability in both the etiology, as well as the recovery from the athlete triad - or, as Dr. Zanker from the Carnegie Research Institute at the Leeds Metropolitan University in the United Kingdom puts it, the simple fact that the "exercise associated reproductive dysfunction in women is attributable to deficits of readily available energy" (Zanker. 2006)

In a couple of more general remarks some of you have recently (not without good reason, by the way) criticized my excessive and in parts random use of mark-ups like bold print or underlining. In the introductory paragraph to today's post the word "readily" is however so important that the underlining is obligatory.

Your hypothalamus does not like to wait, therefore "readily" is the keyword, here!

It is after all the lack of appropriate readily available energy, primarily in the form of circulating glucose, liver glycogen, and adipose tissue triacylglycerol that precedes the low plasma insulin concentration and reductions in total body fat content and corresponding disturbance of leptin secretion, ghrelin, cortisol, thyroid and of course luteinizing hormone (see data in figure 1; the absolute levels from the healthy group may also serve as a reference to compare your own labwork to; mind the units!).

Figure 1: Hormonal and glucose metabolism (* indicates 24h values) of women with functional hypothalamic amenorrhea (not necessarily exercise induced) expressed relative to values in eumenorrheic control; values above the bars indicate the total values of the respective markers in healthy controls and may provide you with some orientation, when you are looking at your own bloodwork (data based on Loughlin. 1998)

In order to avoid / counter the reproductive and associated problems and break out of the vicious circle of the athlete's triad, Zanker proposes the following three steps (based on Zanker. 2006; yet with a couple of additions from my side): 

• Avoid abrupt and rapid weight loss and maintain an “adequate” body fat content, which may be individually specific, but coincides with regular reproductive function.
• Consume adequate amounts of energy to fuel your increased metabolic demands; never go below your resting energy expenditure, regardless of whether you  want to or even have to lose weight.
• Make sure you get an adequate amount of carbohydrates either on a continuous (low GI carbs with every meal) or in a cyclic manner as part of a low(er)* carbohydrate diet with a baseline intake of 90-120g/day and additional carbs after every workout.
  *compared to the RDA of ~60% carbs

"Carbohydrates? But aren't those just making you fat?" With this very question that's now probably on the mind of one or two (or three ;-) of you, we did eventually arrive at the topic of this episode of the Athlete's Triad Series:

Is there a ideal macronutrient ratio that will prevent the onset
and help you get rid of the athlete's triad?

To be honest, I don't know the answer to this question... and although I had almost typed the word "yet" win the place where you now see the "..." , I must admit that I am not even sure if there actually is a definitive answer to this question. What I do have to offer, though, is a couple of things to keep in mind, when it comes to the macronutrient make-up of your diet.

1. There is no such thing as a "bad" nutrient. There are about as many good arguments to vilify the overconsumption of protein, as there are arguments against the usual scapegoats, carbohydrates and fats.
2. Glucose and saturated fats can be essential, too. Just because your body can produce carbs and saturated fats on its own, this does not mean that you do not have to, let alone should not eat them.
3. The optimal macronutrient ratio will change over time - just like and in response to the way your physique, conditioning, lifestyle, training and general stress levels  will be changing. This implies that diet X, which may have worked magically for you, when you got rid of slabs of body fat is now that you are finally in the "normal range", let alone already so lean that your body's alarm bells are constantly ringing, hampering your progress.

And even if the previous comments on the importance of readily available energy and glycogen repletion would suggest that carbohydrates should make up the lion's share of the diet of any athlete trying to recover from the triad (or not to fall victim to it), an extreme high carbohydrate alone is neither guaranteed to solve the problem nor is it a sustainable way of eating you could stick to once you've "carbed" yourself out of the dark hole you have been digging over the past months.

Readily available energy? Does that mean I have to eat sugar all day?

Figure 2: Cortisol (left) and testosterone (right) levels in healthy men after 10 days on high protein vs. high carbohydrate diets (based on Anderson. 1987). Tegelman et al. report similar results from Swedish elite male Ice Hockey players after a reduction of fat and an increase in carbs (Tegelman. 2007)

On the one hand, we've known for over two decades that a high carbohydrate diet based on bread, vegetables, fruit, juices, pastry, and candy having a protein / carb / fat ratio of 10% / 70% / 20% will result in lower cortisol and higher testosterone levels (in men) than a high protein diet with a protein / carb / fat ratio of 44% / 35% / 21% that's based on lots of meat, fish, poultry, egg whites, and a liquid dietary supplement protein supplement (Anderson. 1987; see figure 2). On the other hand, a closer analysis of the data I compiled based on the tabular overview of pertinent studies on amenorrheic from the review by Manore (see figure 3 in the last installment) suggests that real.world advantage of carbohydrates depends on the deepness of the whole you already dug (the deeper the more advantageous) and your willingness / ability to cover or even surpass your daily energy requirements (the more you eat on a daily basis and in at least three square meals spread equally across the day, the less you will depend on the readily available energy from carbs).

Against that background, the high carbohydrate intake (62% of total energy from carbohydrates; nutrient ratio in grams 16% protein, 71% carbs, 14% fats) was probably necessary for the women in the eumenorrheic group with an energy intake of slightly less than 30g/kg body weight (figure 3, R5).

Figure 3: Macronutrient compositions (in kcal!) of amenorrheic and eumenorrheic women from 15 different studies (based on an overview in Manore. 2002)

For the eumenorrheic female athletes who were at, or way above the average mean energy intake of 35g/kg body weight, the "high" carbohydrate intake of 265g/day probably wasn't detrimental. On the other hand, it appears questionable, whether an increase in protein intake from 1.2g protein per kg of body weight to 1.5-2.0g/kg and a corresponding protein to carbohydrate ratio of 25% / 62% would not have been more facilitative to their goals (specifically if those include strength training). The same goes for both, the replacement of yet another part of the carbohydrate ration with an isocaloric amount of fats and the overall role of fats in the etiology of and the recovery from the athlete's triad.

The fat-phobia still loomed large, when the majority of studies was conducted

Part of the problem of reconciling theoretical considerations, such as the "availability advantage" of carbohydrates and the scarce and almost exclusively observational data based on which I compiled the overview in figure 3 of this, as well as the last installment of this series, is that eating patterns of both the eumenorrheic, as well as the amennorheic athletes was geared towards the dietary paradigm of the day. With "the day" being the late 1980s and 1990s, i.e. those years in which the fat-phobia literally climaxed, it should be obvious that the baseline diet was low in fat and high in carbs.

Against that background it should also be clear that anyone trying to "cut calories" would reduce the amount of fats, the "bad energy dense heart killers" and keep the intake of carbohydrates constant (=high). This is probably also, the reason that the ostensible disproportionate lack of fats in the diets of the amenorrheic women vanished, once I weighted the data with the number of participants.

Figure 4: Total dietary intake of protein, carbohydrates and fats (in g; left) and differences between women with and without regular menses (right); data expressed either as simple group averages or weighed for the number of study participants (same sources as figure 3)

The picture that emerges after this adjustment has been done (figure 4, right, light bars) is clear and stands in line with my initial remarks on the primary of readily available energy in the form of circulating glucose, liver glycogen, and adipose tissue triacylglycerol, of which at least the former are way more readily derived from carbohydrates than fats.

And even the triacylglycers do, as the name implies, require a certain amount of glucose for the glycerol backbone (could be produced in the liver from amino acids and/or fats, though) and a minimal amount insulin to be stored in the fat cells (can be secreted in response to high amounts of protein and fat, as well, though).

So no fats? Just carbs and some protein?

Yet though carbohydrates have the availability bonus and proteins are necessary to maintain, better even build muscle mass, you would be ill-advised to steer clear of all dietary fats and, even more so the many good foods that contain them. Not so much because of the "essential" polyunsaturated fatty acid, though. According to a study by Tomten and Høstmark the dietary intake of PUFAs in 20 female runners with regular (n=10) and irregular (n=10) menses (LH levels of 7.6 vs. 2.9 IU/l!) was not statistically different. The intake saturated fats (-28%) and even more the intake of MUFAs (-38%), on the other hand was (Tomten. 2009) and the corresponding total fat-intake of 1.1g/kg body weight was obviously not sufficient to maintain optimal hormonal levels in the presence of a training volume of 7.5h per week.

What about vegetarianism? I know a few of you won't like this, but unless you are at least ovo-lacto vegetarian, i.e. a person who eats dairy and eggs, you are going to have a hard time fueling your athletic endeavors appropriately. After all, vegetarianism is associated with hormonal and menstrual abnormalities even in the non-athletic population, when they are dieting (Pirke. 1986). If you combine a mild energy deficit, as it is often seen in vegetarian, let alone vegan athletes, simply because it's harder for them to cover their energy and specifically protein and fat requirements without guzzling omega-6 oils and soy shakes all day (both not advisable, by the way), it is actually not surprising that Benson et al. mention vegetarianism right along low calorie intakes, nutritional inadequacies and low body fat stores as one of the main contributers to the (female) athlete triad (Benson. 1996).

Now you can certainly argue that all this comes down to the energy density and the correspondingly lower overall energy intake and could have been compensated for, if the women with menstrual irregularities had simply eaten more carbohydrates. In view of the fact that they didn't do so, I can hardly refute this argument. On the other hand, we have seen in the previous installment that an overexpression of GH and ghrelin is in as much part of the problem as too little insulin and a pathologically high insulin sensitivity. And some more fat in the diet (alongside carbs / not as the sole energy source!) couId in fact come handy to get that back in check.

Moreover, having a carb to fat ratio of ~2:1 (in energy equivalents) and a baseline fat intake in the range  of 80-100g (total) as the female runners with regular menses in the Tomton sudy had, has the beauty of never having to throw away the egg yolks, being able to get your share of fatty fish, full fat dairy, Kerrygold butter, virgin coconut and olive oil and beef or better calf liver as well as nuts once in a while. This in turn will allow you not just to stay sane and flexible with your diet, but also to satisfy your need for all those vital micronutrients you won't find in any of E-number laden fat-reduced garbage from the "low fat" shelves at the supermarket.

You see, in the end it all comes back eating simply more of the usual suspects, many people would probably file under "a paleo diet with lots of (safe) starches & fruit to fuel the energetic demands of a hard working athlete", these days.

If we think of the hypothetical daily energy requirement of 2000kcal/day which is often used as a reference for the nutrition information on those products of which you are going to buy less in the future (most real foods don't have nutritional information printed on them, you know ;-), the corresponding "numbers" could be anywhere on a continuum

• from 110g protein / 190g carbs / 100g fats, for someone without an endurance component in his workouts*, 
• to 100g protein / 240g carbs / 80g fats for someone who has a major endurance component and / or follows a high volume lifting routine*
  *pre- and post workout nutrition are not included, here!

This approach would ensure that you get enough protein, appropriate amounts of readily available energy, mainly in the form of safe starches and fruit, quasi unlimited amounts of vegetables and so much fat that you don't have to resort to the devastating "chicken breast, rice and broccoli diet", which will only worsen your situation.


References:

• Anderson KE, Rosner W, Khan MS, New MI, Pang SY, Wissel PS, Kappas A. Diet-hormone interactions: protein/carbohydrate ratio alters reciprocally the plasma levels of testosterone and cortisol and their respective binding globulins in man. Life Sci. 1987 May 4;40(18):1761-8.
• Benson JE, Engelbert-Fenton KA, Eisenman PA. Nutritional aspects of amenorrhea in the female athlete triad. Int J Sport Nutr. 1996 Jun;6(2):134-45.
• Laughlin GA, Dominguez CE, Yen SS. Nutritional and endocrine-metabolic aberrations in women with functional hypothalamic amenorrhea. J Clin Endocrinol Metab. 1998 Jan;83(1):25-32.
• Manore MM. Dietary recommendations and athletic menstrual dysfunction. Sports Med. 2002;32(14):887-901.
• Pirke KM, Schweiger U, Laessle R, Dickhaut B, Schweiger M, Waechtler M. Dieting influences the menstrual cycle: vegetarian versus nonvegetarian diet. Fertil Steril. 1986 Dec;46(6):1083-8.
• Tegelman R, Aberg T, Pousette A, Carlström K. Effects of a diet regimen on pituitary and steroid hormones in male ice hockey players. Int J Sports Med. 1992 Jul;13(5):424-30.
• Tomten SE, Høstmark AT. Serum vitamin E concentration and osmotic fragility in female long-distance runners. J Sports Sci. 2009 Jan 1;27(1):69-76.
• Zanker CL. Regulation of reproductive function in athletic women: an investigation of the roles of energy availability and body composition. Br J Sports Med. 2006 Jun;40(6):489-90; discussion 490.

Meal Timing, Glycemic Index & Load: Human Study Probes Whether "Hitting Your Macros" Really is All That Counts

High or low GI, carbs in the morning or in the evning, cookies and dingdongs or all bran. So many questions and way too many answers from rodent studies or studies in obese diabetics... but what are Mr. and Mrs. Healthy Average Joe supposed to do?

In a recently published paper, Linda M. Morgan, JiangWen Shi, Shelagh M. Hampton and Gary Frost take yet another look on a concept that has lost much of the momentum it had only a decade ago: The GI and / or GL paradigm (GI: glycemic index (abstract unit); GL: glycemic load, i.e. GI / actual amount of food) and combines another paradigm, which is still gathering momentum within the medical science community - the issue of nutrient timing, in order to answer the following questions:

• Will a large evening energy and carbohydrate load cause an increase in postprandial glucose that is comparable to the same amount of energy and carbohydrates in the morning?
• Will a high glycaemic excursions in the evening be ameliorated by decreasing the glycaemic index (GI) of the meal?

Or put simply: Does carbohydrate and energy timing make a difference and can this difference be mitigated by chosing the "right", i.e. low glycemic carbs (e.g. sweet potato vs. white bread)?

White bread king or all-bran pauper - is that  the question?

To answer this world-shattering question and actually prove their hypothesis that both, i.e. having carbs in the evening and having those in the form of high glycemic index foods, will have negative consequences on postprandial glycemia, the scientists picked six healthy volunteers (four females, two males; mean age 30 +/- 4.3 years, BMI 21·6 +/- 1.3 kg/m²) and randomly assigned them to a follow one of the four following dietary protocols:

• Low GI (average GI = 34), with the majority of energy load consumed in the morning (LGI-am)
• Low GI, with the majority of energy load consumed in the evening (LGI-pm)
• High GI (average GI = 84), with the majority of energy load consumed in the morning (HGI-am)
• High GI, with the majority of energy load consumed in the evening (HGI-pm)

with identical energy content of approx. 8368 kJ (2000 kcal) for the whole day on four individual intervention days with a minimum of 7 days between each of the tests. Breakfast was given at 09.30 hours, lunch at 13.30 hours and the evening meal at 20.30 hours - subjects were at the laboratory for the whole day. Blood samples were taken 2h postprandial and blood glucose levels were monitored continuously via a "MiniMed continuous glucose monitoring system" that senses interstitial glucose by electrochemical detection in subcutaneous interstitial fluid in 5 min intervals.

Figure 1: Composition of the two test diets (low GI, blue; high GI read) and individual macronutrient breakdown of the test meals the subjects consumed on two seperate occasions (based on Morgan. 2013)

It does not take a nutrition expert to see that despite the obvious differences with respect to the glycemic index and load, even the allegedly healthy low GI diet with all-bran for dinner* and a macronutrient composition 72% carbohydrates 14% protein and 14% fat is not exactly what the latest research would suggest to be a healthy, let alone a "physique enhancing" diet.

*note: The scientists probably chose similar foods for breakfast and dinner, because the study design required those to be exchangeable.

Against that background it is still astonishing how much of a difference...

• 99% higher fiber content,
• -60% lower glycemic index (GI), and
• -63% lower glycemic load (GL)

... actually make when it comes to the effect of isocaloric meals with identical macronutrient compositions (see figure 1, right):

Figure 2: Total area under the curve for interstitial glucose (0–20 h), postprandial plasma insulin, TAG (**mind the text for info a potential typo, here) and NEFA (0–2 h after each meal) in six healthy volunteers following either a high-glycaemic index (HGI) or a low-glycaemic index (LGI) diet, with most of the energy consumed either early (LGI-am, HGI-am) or late (LGI-pm, HGI-pm); all values expressed relative to respective statistical mean (data calculated based on Morgan. 2013)

I guess I don't have to tell you that the image that emerges here stands in line with the as of late largely ignored glycemic index paradigm the underlying message of which is: It is not simply the amount of sugar you eat,  but rather how fast / hard it hits your blood stream that determines it's impact of on your glucose metabolism. And with respect to the latter, the researchers remark:

"Glucose and insulin responses showed broadly similar patterns. Both meal timing and quality of carbohydrate affected postprandial glucose and insulin responses (P < 0.01). The area under the glucose and insulin response curves was greatest for the HGI-pm meal regimen. The HGI-pm meal regimen produced a significantly greater postprandial area under the glucose curve than for any of the other three meal regimens (P < 0.05). The postprandial area under the insulin curve was significantly greater than both the LGI regimens (P < 0•05). Postprandial insulin resistance measured by homeostatic model assessment was also significantly greater for the HGI-pm meal than for the two LGI meals (P < 0•05)."

However, since Morgan, Shi, Hampton and Frost also state that "[p]ostprandial TAG and NEFA levels were not affected by meal timing or carbohydrate quality", I do suspect that there is a typo in table 3 of the original study, where it says that the TAG would be 5.04 mmol/l x h (probably is 6.04) and thus more than 15% lower than the average (TAG levels and insulin resistance usually go hand in hand, so it is really very unlikely that the 5.04 mmol/l x h is correct).

So what's the take home message here?

The only question that still has to be answered would be "King or pauper? At least with regard to the former, the best thing I can to is to suggest you read both the posts on "Breaking the Fast" and the "Carbs Past 6PM Posts"  (Part 1 & Part 2). When you have done that your perspective on the importance of breakfast and the purported fallacy of having a large dinner should already have changed. The things that are still left to do is not fool yourself into the false belief that you can pound whatever junk you want (as long as it fits your macros). As the glucose curve of the high GI arms (light color) in the figure above goes to show you, your body won't be happy when you get your "carb macros" from sugary junk.

Stick to starchy (or "save carbs", if you will) and fruit. Use veggies to fill you up. Use coconut & olive oil and the fats that are already in your meats, fish and dairy products to achieve baseline fat intake of at least 40-50g (all together). Aim for a 100-120g carbohydrate basis, diverge towards the lower side, when your body fat is high, you can't train or you're dieting and towards the higher side, when you are already very lean, have a high training volume, or are trying to build muscle. Complement that with min. 20g of quality protein with each meal. Don't deprive yourself on any nutrient completely and ramp up the total amount of food (at the given ratio) to fulfill your energy requirements.

In that, avoid processed food sand rely on whole foods, whenever possible (>90%),. Use food supplements* only where it makes sense, e.g. a protein shake post workout (*creatine for example would not be a "food supplement", since you can NEVER get the amounts that are necessary to supersaturate your stores from meat alone) and don't forget to live about all that "dieting" and thinking about the best ways to eat, please!

So if we assume that my assumption with respect to the triglyceride values in the originally published study are correct and we are simply dealing with a typo here, the next questions which arise here, are...

1. What is / are the reason/s that the lipid metabolism did not suffer?
2. How reliable is the HOMA-PP, i.e. the postprandial assessment of insulin sensitivity via the homeostasis model assessment? 
3. What does all this mean for you? Does meal timing not make a difference and are macros all that counts? 

As far as (1) goes, the answer is pretty simple: With a diet that was that low in fat and not overabundant in energy (2,000kcal for both diets) any potential the negative downsides on lipid metabolism will take their time to show. The acute ingestion of three high GI meals on a single day or modifications in their distribution across the day won't have much of an effect in healthy individuals, such as the four women and two men in the study at hand (in diabetics and especially patients with NAFLD things will probably look different, though).

The absence of changes in lipid metabolism after one day on high vs. low GI diets w/ different meal timing patterns yields answer #1 to question (3): If you are healthy the occasional day with junk food won't hurt you as long as you keep the total amount of energy at bay and jump back on the "healthy diet" wagon the very next day.

On the other hand, if only a single day of high GI food consumption can have such a pronounced impact on the postprandial HOMA levels, this raises the question how reliable this "long term measure" of glucose sensitivity actually is. Obviously, you should not go to the doctor's office and have your HOMA measured, at a morning after a day with three SuperSize Meals from McDonalds (even if you have been fasting after supper at night before, as the participants in the study at hand did) - unless you want a prescription for meformin, of course ;-)

It would however be likewise unwise to "do everything right" for three (maybe even just one day) before you head to the doctor to get blood drawn, just to be able to rejoice over a HOMA reading that does by no means represent your "normal" insulin sensitivity. This may make your doctor happy and spare you getting ticked off, but could have you run around pre-diabetic unnoticed for months if not years - maybe so long until the first irreversible damage has already been done.

The high susceptibility of HOMA measures to acute dietary modifications yields answer #2 to question (3): If you want know where you stand, don't make last minute changes to your diet before you get blood drawn. After all, the 90:10 rule (better 95:5 rule ;-) applies both ways - the 90/95 days of consistent eating patterns will decide whether you are lean, muscular and above all healthy or fat, undermuscled and sick.


References:

• Morgan LM, Shi JW, Hampton SM, Frost G. Effect of meal timing and glycaemic index on glucose control and insulin secretion in healthy volunteers. Br J Nutr. 2013 Oct;108(7):1286-91.

Carbs Past 6PM Reloaded: Circadian Shifts in Leptin and Ghrelin + Rising Adiponectin During the "Carb-Fast" Could Explain the Efficacy of Eating All Carbohydrates at Night

Image 1: Paul Bart (Kevin James) in Mall Cop (Columbia) probably would be better off weight- and health- wise without his Segway, which is by the way among the "50 Worst Gadgets of the Decade" in the Business Insider hall of shame from 2009 (Barret, Brian. 2009)

The SuppVersity was the first place you read about the how "Carbs past 6pm Will Make You Lean" (at least about the non-anecdotal scientific evidence) and for 99% of you, this will probably be the first time you read about the "follow up paper" on the original study, which was originally intended to induce a shift in the circadian pattern of leptin secretion in order to make use of its fat burning effects over night. Exactly this is the focus of a follow up paper that's soon going to be published in Nutrition, Metabolism & Cardiovascular Diseases (Sofer. 2013).

Israeli Police Diet Acadamy Reloaded!

Now the bad news is that the news are only partly new. In other words, the Israeli scientists only reevaluated the original data which was based on 63 overweight police officers who finished the original "don't eat carbs before dinner study."

And if that was not already enough, the complete hormonal profiles which had been collected on days 0, 7, 90 and 180 of the study period were only available for 39 of them.

Figure 1: 24h leptin profile before and after the intervention in the control (left) and experimental (right) group
(graph adapted from Sofer. 2013)

Still, the data in figure 1 does support the original hypothesis that the mechanism due to which the participant on the experimental diets (composition see figure 3 in "Carbohydrates Past 6PM Will Make You ... Lean!") lost ~2% more weight, and ~4% more body fat was in fact a shift in the circadian expression of leptin:

I suggest you go back to the original "Carbs past 6pm Will Make You Lean" post to read up on the details; unless you're a longstanding reader and this reminder is enough for you.

"On day 0 both groups demonstrated typical concave diurnal leptin curves, including a fall throughout the hours of 08:00-16:00, reaching a nadir at the afternoon and a rise from 16:00. On day 180, leptin curves were lower compared to day 0 in both groups. In the experimental group, the curve became more convex with a nadir only in the evening and not in the afternoon (figure 1, right). A significant difference was observed within the experimental group between day 0 and day 180 in the morning and in the evening (p = 0.023 and p = 0.021, respectively). For subjects in the experimental group that had complete data, the change in evening measurements from day 0 to day 180 was significant(p = 0.024). Using these data, the change in evening measurements was significantly greater than the afternoon and the noon change (p = 0.009 and p = 0.014, respectively). In the control group, a significant difference was observed between day 0 and day 180 at noon (p = 0.042). This result was also found for subjects with complete data (p = 0.045)." (Sofer. 2013)

What's also noteworthy is that the sparse information the scientists had on the ghrelin levels of their participants (believe it or not, but the nurse or whoever took the blood samples must have messed up, so that much of the data was lost) would suggests that the "post 6pm group" (=experimental group) were freaking hungry in the evening (see figure 1, right), but this was not the case, contrary to the subjects in the control group which had carbs from AM to PM, they did rather expose an "enhanced daytime satiety" an observation based on which Sofer et al. rigthly state that

"[...] the alteration in ghrelin’s peak from daylight hours to the evening just before dinner was another cause for the elevated daylight hour satiety, improved persistence in the weight loss process and better anthropometric outcomes that were reported [16]." (Sofer. 2013)

Next to with the circadian shifts in leptin and ghrelin levels, the pronounced increase in adiponectin (see figure 2), a reliable marker for an improved glucose tolerance, the "carb binges" which as you will probably remember included desserts such as ice-cream and co (see figure 3 in "Carbohydrates Past 6PM Will Make You ... Lean!"), probably is the third pillar of the superiority of the past-6PM carb regimen over the conventional "eat small amounts of carbs all day" approach  the control group was following.

Figure 1: 24h Adiponectin profile before and after the intervention in the control (left) and experimental (right) group
(graph adapted from Sofer. 2013)

In conjunction those three made the "impossible possible": Eat all instead of no carbs past 6PM and lose weight! Now the unfortunate truth is that this works well for people with compromised insulin sensitivity and anywhere between 15-20% body fat to shed before they approach the level of leanness (<20%) most of you probably started out with, whether it will work similarly well for significantly leaner, physically active individuals, on the other hand, remains to be seen.

Video 1: I don't want to be a spoil, but the weight loss program of the Stadtwerke Cologne which works by simply skipping dinner (!) and without any caloric restriction got some series attention here in Germany. Why? Well, it simply works... so what does this tell you? Maybe it's more about helping AMPK come to it's own, instead of stuffing yourself with readily available energy 24/7, than about exact timing or meticulously calculating macro compositions?
(click here to watch Quarks & Co.)

Bottom line: Irrespective of my all doubts about the applicability of the very same diet principle in a context, where the goal is to get really ripped and not simply non-obese, the study at hand (and I am referring to the whole experiment, here not just the last paper) does confirm that there is more to dietary success than calories in vs. calories out that having breakfast like a king is not a necessity (nuts + coffee, which was the standard breakfast in the experimental group, or nothing, which is Adelfo Cerame's standard breakfast, work just as well) and that the influence of circadian rhythms goes far beyond our sleep-cycles... which reminds me that I'll do my very best to get into more details on that in the coming episode III of the SuppVersity Circadian Rhythm Series on Sunday. Until then, try not to lose the beat ;-)

References:

• Barret, Brian. The 50 Worst Gadgets Of The Decade. Business Insider. Dec 31, 2009. < http://www.businessinsider.com/the-50-worst-gadgets-of-the-decade-2009-12?op=1 > retrieved on Aug 24, 2013.
• Sofer S, Eliraz A, Kaplan S, Voet H, Fink G, Kima T, Madar Z. Changes in daily leptin, ghrelin and adiponectin profiles following a diet with carbohydrates eaten at dinner in obese subjects. Nutr Metab Cardiovasc Dis. 2013 Aug 14.

Women Have a Much Harder Time Losing Body Fat Than Men, But Both Benefit From Doubling Their Protein Intake!

Image 1: Looks good, tastes good, is good - and contrary to zinc, ingesting 2x the RDA will help you lose body fat, instead of setting you up for insulin resistance.

Enough of useless (ALA, zinc) and useful (glutamin) supplements for at least 24h! Let's get back to what really counts: Training? No, not today,.. the other thing! The one, which is actually to be supplemented - your diet! Believe it or not - even after all those years, I am finding time and again that the food you put into your mouth has much more pronounced effects on the ways you look feel and perform than any of the countless useless and useful supplements. Accordingly and in response to the futile notion of "calories in vs. calories out" and the bomb-calorimeter representation of the human metabolism as a simple furnace, the past couple of years have seen an increasing public and (as of late) scientific interest in the effects varying macronutrient compositions will have on your ability to shed weight and, more importantly, to keep it off in the long run.

Submitted on December 30, 2011 and published in the latest issue of the Journal of Nutrition & Metabolism (9:55) the results of a "randomized clinical weight loss trial" comparing more or less isocaloric (-500kcal/day) weight loss regimen in 130 (58 male, 72 female) overweight middle-aged (40-56) subjects (BMI  =  32.5  ±  0.5 kg/m²) provide further insights into the real-world effects of  prescribed minimal protein intake levels on the outcomes of a 4 months weight loss and 8 months weight maintenance intervention (Evans. 2013).

RDA = 0.8g/bw vs. 2x RDA = 1.6g/bw protein - Round 1: Education & Adherence

In many of the previous posts on this issue (e.g. "High Carb vs. High Fat for Obese Type II Diabetics and What Really Happens, When Science Meets Real Life"), adherence or even an appropriate awareness of what "high protein" actually means turned out to be one of the main culprits as far as the significance of respective data is concerned (Krebs. 2013). In this respect, the subjects in the study by Evans et al. who were supported by a pretty extensive educational and support program that included

• the provision of electronic food scales and instruction on how to weigh and record food servings at all meals (logs were monitored for compliance on a weekly base!)
• a specific diet program with detailed instructions from a research dietitian including the menus, food substitutions and portion sizes
• an obligatory weekly 1 h meeting at the weight management research facility, where they received dietary counseling, had the ability to pose questions and instructions referring to the minimum of 30 min of walking 5 d/wk

constitute a positive exception from the average "study participant" who receives a handout with instructions and a clammy handshake for his/her willingness to step on the scale twice within a given time-frame.

Figure 1: Energy intake (total) from different macronutrients (left) and relative reduction compared to basesline in the 4-month weight loss and the subsequent 12 months "maintenance" period (based on Evans. 2013)

Based on the activity logs, the average amount of exercise was less than 100min/wk and not different between the two treatment groups. As far as the drop outs are concerned, there was yet a trend for lower drop out rates of the male participants in the protein compared to the carbohydrate group (9/28 vs. 18/30). 

Figure 2: Adherence to the prescribed macronutrient ratios was similarly "good" for men and women in both the high carbohydrate and high protein arm of the study (based on Evans. 2013)

The overall adherence to the prescribed nutrient ratios, i.e. 15% protein, 55% carbohydrates and 30% fat in the high carbohydrate and 30% protein, 40% carbohydrates and 30% fat in the high protein group was similarly good (the deviations were smaller than one standard deviation) among both men and women; and still, the net results of the study appear somewhat disappointing - at least if you make the all too common mistake of judging the outcome of an already intrinsically mislabeled "weight loss" intervention solely by the figures on your scale, which were, for the subjects in the study at hand, identical for both groups (PRO:-10.7  ±  6.8 %, CARB:-10.1  ±  6.2 %, expressed relative to body weight at baseline).

Feminists beware! Life is not fair...

A closer analysis of the data does yet reveal that despite an overall greater reduction in calorie intake in the high protein group (-31% vs. -22% in the weight loss phase and -27% vs. -16% in the maintenance phase) and slightly but statistically non-significantly greater body fat loss in the male participants on the high carbohydrate diet at the end of the maintenance phase, the "net" effect on the lean to fat mass ratio in men and women speaks in favor of increased protein intakes during phases of reduced energy intake.

Figure 1: It is obvious that compared to baseline the loss in body fat (expressed relative to baseline, left) was significantly more pronounced in the male compared to the female participants; the favorable effects of the high(er) protein diet on the lean to fat mass ratio (4% and 6% greater improvements) is yet of even greater importance for the ladies.

There is yet no denying that middle-aged women are - irrespective of their diets - having a substantially harder time losing body fat than men of the same age. In view of the fact that this is at least partly mediated by their significantly lower lean body mass to fat mass ratio (1.3 in women vs. 2.2 in men), the aforementioned protein sparing effects of "high" protein diets are of even greater importance for female dieters than for their male peers (cf. figure 3, right) - unfortunately, even the latter rarely rarely spare a thought about that, when their short-sighted and often likewise overweight Dr. tells them "you got to lose weight, if you want to see your grand children graduate, buddy!"

... and if you want sexual equality you got to lift weight and eat your meat ;-)

Against that background the results of the recently published exercise-only trial by Washburn et al. come to mind (cf. "Strength Training Ain't For Women -  Really!?" and Washburn. 2013). In the study at hand, The absence of at least a minimalist strength training regimen, as it was employed in the Washburn study, could in fact be one of the major reasons for the small overall effect size Evans et al. observed in their "walk in the park if you will" study. Eventually, the preservation of an already low amount of lean tissue mass is one thing, increasing the latter and thusly building the metabolic advantage of greater lean muscle mass, based on which the male study participants shed roughly 15% more body fat within the 12 month than their female peers is yet another one, of which I can hardly repeat often enough that it will not turn Angels into Divas over night (see image 2). And while you can easily regain 2 pounds of fat you lost, you will have to acknowledge that the lean mass you have either never built or lost over years of mainstream dieting, won't come back easily (cf. Beavers. 2011).

Image 2 (unkown Facebook source): Strength training and a high protein diet don't turn Angel's into Divas over night - what a pity ;-)

Bottom line: Regardless of whether you are a woman or a man, an angel or a diva, Homer Simpson, Peter Griffin, or Stanley Smith (cf. "Stocktaking, Goal Setting, -Tracking & -Resetting to Achieve a Healthy Weight & Shed Excess Body Fat"), greasy steaks, eggs, fish, dairy and a gym membership will not just have a much more pronounced impact on the outcome of your next diet, than all the diet products and books your money can buy, as an elementary part of your new lifestyle they will also lay the foundation of your future health - and what's even better: You will have more than enough extra years to spend all the money you would otherwise have spent on all those gimmicks, false promises, useless supplements and defacing cosmetic surgeries! Now you tell me eating a high(er) protein diet and spending time in the gym instead of the office was uneconomical ;-)

References:

1. Beavers KM, Lyles MF, Davis CC, Wang X, Beavers DP, Nicklas BJ. Is lost lean mass from intentional weight loss recovered during weight regain in postmenopausal women? Am J Clin Nutr. 2011 Sep;94(3):767-74. Epub 2011 Jul 27.
2. Evans EM, Mojtahedi MC, Thorpe MP, Valentine RJ, Kris-Etherton PM, Layman DK. Effects of protein intake and gender on body composition changes: a randomized clinical weight loss trial. Nutr Metab (Lond). 2013 Jun 12;9(1):55.
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