Showing posts with label RDA. Show all posts
Showing posts with label RDA. Show all posts

Tuesday, June 18, 2013

Profitable Revelation! Inhabitants of the Affluent Western Hemisphere Don't Meet "Their" RDAs For Important Nutrients. "Scientists" Call to Action, I Call to Calm Down.

Image 1: Nothing sells like FDA-approved supplements and federally supported fortified foods. And whenever you want to sell more snake oil, just pay for another study on "nutrient deficiencies"
There are two things you can shovel truckloads of money with in the realms of dietary supplements and convenience foods. Those are dreams, such as the dream of a lean and muscular physique and FDA approved but for customers non-verifiable promises of  the absence of future ailments. And while such profane things as wanting to get big and buffed or even simply "looking good naked" is looked down upon by the majority of average Joes and Janes (I don't want to go into the underlying psychological reasons here ;-), the use of the latter is generally regarded as a useful if not necessary means that will not just help us preserve our health, but will also sooth our guilty conscious of not being able to break ourselves of our bad dietary habits. Against that background it's good that we have such great scientists and policy makers who will base their wise decisions on totally unbiased and all-encompassing scientific data from research teams such as as the one from DSM Nutritional Products Limited in Kaiseraugust, Switzerland, and Parsippany, NJ, USA (Troen. 2013).

On average, we are all the same, right!? Our governments obviously don't think so...

Morover, the decisions of those policy makers are not just rooted in science, they also hold another, maybe even more important good in highest esteem: Equality! And though, equality is one of the principles the Western civilization often boasts of, it seems as if when it comes to our dietary "needs", as defined by the individual dietary guidelines, you, my mostly American friends, must be somewhat different.
Figure 1: Reference intakes for selected vitamins in Germany, UK and the Netherlands expressed relative to the US RDA (data based on overview in Troesch. 2013)
This would at least be the logical conclusion you would have to draw based on the in parts pronounced differences between German and US RDAs (see figure 1), which would suggest that my I need ~30% more vitamin D than you do, while our friends in the UK either don't need it at all or cannot agree on a reference intake and my neighbors to the West, must assume that they get more than enough vitamin D from sunbathing at the beaches of the North Sea to get away with only 100IU of vitamin D per day; and their low recommendations for vitamin E are probably based on the rationale that they traditionally use beef fat instead of vegetable oils to fry their fries *rofl*

You are deficient, my friend! Go get your fortified foods ans supplements, NOW!

Now, as funny as that may seem, in the end these discrepancies only underline three fundamental problems that are rarely addressed when scientists analyze data to finally get to the (nutritional) root course of modern disease:
Want to learn about where you stand in terms of the RDA?

I got some help from my friends over at Highbrow Paleo, who felt the following tools are particularly helpful to estimate or calculate your daily micro- and macronutrient intakes:
You know that I am not a big believer in logging your food intake and making calories in vs.calories out calculations. So, for your own psychological well-being try not to get addicted to these tools only to end up as yet another food neurotic on certain bulletin-boards ;-)
  1. the RDAs are more or less arbitrary - While we do know pretty certain which dosage of a certain nutrient is vitally important, when everything else, i.e. nutrition, exercise, stress, etc. is "normal" (whatever that may be), we have almost no clue how deficiencies, let alone the overabundance of one nutrient affect the need / optimal intake of another. A good example here would be calcium - one of my favorites, by the way: While we are stuffing our elderly (in particular women) with calcium supplements to "protect" their bones with little success, Dawson-Hughes et al. have shown in 2009 already that you can effectively reduce bone resorption, i.e. the leeching of calcium from the bones, by supplemental potassium bicarbonate, while just throwing more calcium and vitamin D at older men and women will at best increase renal calcium excretion, at worst lead to kidney stones and vascular calcification (Dawson-Hughes. 2009)
     
  2. the RDAs are light years are usually one or two decades behind contemporary science - Despite being an outspoken critic of the current vitamin D hysteria, the absence of a concrete RDA for vitamin D in the UK is just one of the most obvious examples of how the endless discussions of top-class experts lead to an grossly negligent gap between the latest results from scientific research (which in and out of itself often take months to be published and years or decades to be accepted) and their concrete implementation into the guidelines.
     
  3. the RDAs lack any regard of individuality or specificity - although the different RDA's in the USA, Germany, the UK and the Netherlands would suggest otherwise, you are all identical clones of an imaginary average Joe or Jane for the policy makers; and as if that was not enough, the same applies for the nutrients as well: "Vitamin A? Yeah, that's beta carotene, right?" And vitamin A vs. carotene (even alpha vs. beta caroetene) is only one of the many examples (others are folate vs. folic acid; alpha tocopherol usually equated with "vitamin E" vs. gamma-tocopherol, let alon the tocotrienols, etc.), for which we know by now that lumping them together under common names, can easily lead to imbalances with pathological consequences.
Against that background my rationale for posting the following data on what scientists believe Mr. and Mrs. average US/UK/GER/NL citizen are missing out on and of which nutrients they may in fact get plenty is to create an incentive to take a couple of minutes and plug your own food data into one of the countless free online devices (see red box above for some references) to see where you as an individual are standing - and I bet, the majority of you will see results that are fundamentally different from those Troesch et al. summarize in their paper:
  • Vitamin D: Irrespective of whether or not you believe that it does make sense to consume the lion's share of a "vitamin" that is supposed to be produced in your skin and is thus, due to its actions on almost every cell of your body, essentially not a vitamin, but a hormone, it is somewhat alarming that even in the Netherlands, where the RDA is hilarious 100IU 5-25% of the men and 25-50% of the women fail to achieve their recommended daily allowance - 2 1/2 large egg yolks alone would provide them with more than that! With the higher RDA's in Germany and the USA, the percentage of people who do not meet their daily allowances is >75%!
  • Vitamin A: I am by no means surprised that vitamin A is not mentioned in the scientists mini-summary in the abstract. After all, it's bad for you! Right? No... freaking, no! And it's certainly likewise not good for way more 75% of the US citizens not to meet their RDAs for vitamin A and that despite the fact that the scientists lumped all "vitamins A" together! In the Netherlands and the UK, ~50% have an adequate intake and over here in Germany only 25-50% of my the average Joes and Janes are below their RDA cut-off, which could, just as the vitamin D problem by the way, readily be solved by eating a piece of liver from time to time. Some fatty fish, eggs and of course vegetables on a daily basis would yet serve the same purpose and would, which may turn out to be of even greater importance deliver a very balanced spectrum of various forms of pre-vitamin A (carotenes) and retinol.
  • Figure 2: Changes in reasoning behind supplement use in 2010 (French. 2011)
    Folic Acid and other B-vitamins: An interesting observation can be made for the B-vitamins, where the citizens of the land of both fast food and eager food-intoxi.... ah, I mean "fortification" (obviously the US) appear to be way better off than their poor fellows in Europe. Especially here in Germany, we should really wonder that we are not much sicker than you, after all, not all our products are enriched with high amounts of bio-unavailable folic acid so that we more than 75% of us do not meet our RDAs for this unquestionably important, but in its unnatural supplemental form not very controversial vitamin. In 2006, for example, Troen et al. report reduced immune function from excess folic acid build-up in the blood of post-menopausal women (Troen. 2006) and Halsted reports in a more recent paper that the "widespread use of supplemental multivitamins" in conjunction with the "fortification of the US diet with folic acid has resulted in high serum ... "[...] folate levels in much of the population" (Halsted. 2008)
    high folate levels that have been associated with increased risk of cognitive decline in aging people with low vitamin B12 status, decreased natural killer T-cell immune function and increased risk of recurrent advanced precancerous colorectal adenomas and breast cancer" (Halsted. 2008)
    Against this background it should be allowed to ask, whether the "average American" with his "adequate" (>95%!) folic acid intake really is better off than the "average German" who is unlikely to get his RDA of folic acid (>75%). 
For the scientists who (surprise!) happen to work for DSM Nutritional Products Ltd., the observations they present in form of stylized "traffic lights", with all those yellow and red "lights" signifying impeding danger and the need to take action, suffice to conclude that there is not just a gap "between vitamin intakes and requirements for a significant proportion of the population even in the most affluent countries", but that the latter would also be "a call to action 100 years after the term 'vitamine' [sic!] was coined" (Troesch. 2013)
If this post got you interested in an in-depth look at nutrient fortification its uses, abuses, benefits and downsides, I suggest you check Paul Jaminet's article on the issue at his "Perfect Health Diet Blog" (Jaminet. 2013). It would be pointless for me to repeat what Paul has already laid out in his concise and - as us physicists like it - well-referenced summary ;-)
And while Mrs Troesch and her co-authors do not state that explicitly, it should be obvious what this "call to action" will amount to... !? Right! More nutrient "fortified" foods and more randomly assembled multi-vitamin products, instead of less junk and more health (=real) food in everyone's diet.

References:
  1. Dawson-Hughes B, Harris SS, Palermo NJ, Castaneda-Sceppa C, Rasmussen HM, Dallal GE. Treatment with potassium bicarbonate lowers calcium excretion and bone resorption in older men and women. J Clin Endocrinol Metab. 2009 Jan;94(1):96-102.
  2. Halsted CH. Perspectives on obesity and sweeteners, folic acid fortification and vitamin D requirements. Fam Pract. 2008 Dec;25 Suppl 1:i44-9. Epub 2008 Sep 30. Review. 
  3. Jaminet, Paul. Food Fortification: A Risky Experiment? PerfectHealthDiet.com. March 23, 2013 < http://perfecthealthdiet.com/2013/03/food-fortification-a-risky-experiment/ > retrieved on June 18, 2013.
  4. French S. Natural Marketing Institute. The US Botanical Market: Latest Consumer Insights. Natural Marketing Institute. March 2011.
  5. Troen AM, Mitchell B, Sorensen B, Wener MH, Johnston A, Wood B, Selhub J, McTiernan A, Yasui Y, Oral E, Potter JD, Ulrich CM. Unmetabolized folic acid in plasma is associated with reduced natural killer cell cytotoxicity among postmenopausal women. J Nutr. 2006 Jan;136(1):189-94.
  6. Troesch B, Hoeft B, McBurney M, Eggersdorfer M, Weber P. Dietary surveys indicate vitamin intakes below recommendations are common in representative Western countries. Br J Nutr. 2013 Jun 13:1-7.

Sunday, June 2, 2013

Tocotrienols: What They Are, What They Do & How They Work + Why the RDA of Palm Olein is NOT 1xCup Per Day

Image 1: If you wanted to get the tocotrienol levels a producer of respective supplements says are  "required", you would have to eat at least 200g palm fruits a day. Alternatively, you can resort to 4kg of oats, if you like those better... What? you are wondering that you are not dead by now? After so many years of tocotrienol deficiency from not getting your 4kg of oats?
The long lists of pathologies related to vitamin E deficiency include, among others, all sorts of degenerative diseases from ataxia over general muscle degeneration to degeneration of sperm and subsequent infertility. But despite the fact that there is a pretty substantial amount of evidence that would suggest that a diet rich in vitamin E could not just prevent the aforementioned pathologies, but would also protect us from many of the currently prevalent ailments of western society such as obesity and coronary vascular disease (Mishra. 2003; Rimm. 1993), respective trials with dietary supplements usually show no, or even negative effects. I have already addressed a couple of  reasons why the benefits of dietary vitamin E intake often cannot be replicated with supplements in previous posts. The most significant one, probably is the absence of the "right" mixture and ratio of alpha-, beta-, gamma- and delta-tocopherols and, as an emerging contributer, the total absence of tocotrienols in the vast majority of vitamin E supplements and almost 99.9% of the pertinent trials.

What are tocotrienols? And what do they do?

I could now rant about the structural differences between the two, with the tocotrienols being an unsaturated variety of the tocopherols with a isoprenoid side chain, but I guess it is enough to know that due to  differences in their molecular structure, they also differ in their effects on the human body, of which you may already have apprehended that their cholesterol lowering effects were the first to attract the attention from researchers (Qureshi. 1986). Within the last 26 years researchers from all around the world have identified additional health benefits, the most prominent of which are...
  • Anti-cancer effects (Kato. 1985; Sundram. 1989; Weng. 2009),
  • General antioxidant effects (Newaz. 1999),
  • Brain specific antioxidant effects (Khanna. 2003),
  • Exercise-specific antioxidant effects (Lee. 2009),
  • Cardiovascular disease (Shibata 2009)
  • Diabetic neuropathy (Kuhad. 2009)
  • Bone health (Ahmad. 2005)
  • Metabolic syndrome (Weng. 2011)
  • Antithrombotic effects (Qureshi. 2011)
  • Endocrine health (Yu. 2005)
  • Liver health (Patel. 2013)
The purpose of today's SuppVersity article is yet not so much to compile the most extensive list of potential, purported or demonstrated benefits of tocotrienols, the major dietary sources of which are (Kobayashi. 1975; Tan. 2011)
  • rice bran oil (50:50 tocopherol:tocotrienol ratio), 
  • palm oil (25:75 tocopherol:tocotrienol ratio), and 
  • annatto (0.1:99.9 tocopherol:tocotrienol ratio) oil
  • human breast milk (!) [though this is probably no major source for you ;-]
but rather to take a look at an intriguing chart of the various molecular targets (Aggarwal. 2010) and discuss the implications:
Figure 1: Molecular targets (left) and proteins that directly interact with tocotrienols (right; adapted from Aggarwal. 2010)
As you can see  without even looking really close at the above graphic, the number of those targets is vast. Another thing you should see right away is that the effect of the tocotrienols is mostly inhibitory (red ovals in the left) and include a couple of old foes, such as:
  • the inflammatory cytokines & transcription factors: IL-1, IL-6, TNF-alpha, nf-kappabeta, IL-8 (probably involved in auto-immune reactions), PF-A4 (increases platelet aggregation and thus thrombosis risk)
  • factors involved in angiogenesis and cardiocascular disease: VEGF (vascular growth factor, involved in CVD) and its receptor VEGF-r, VCAM-1 (increases adhesion of immune cells to the endothelial wall)
  • kinases involved in the cell cycle and apoptotic regulators: CDK's, PKC, pERK, etc. & survivin, IAP-1 & 2 etc., but also telomerase, which are all involved in the proliferation of cancer
  • enzymes involved in inflammatory processes: eNOS, iNOS, COX-2, etc.
On the upregulatory side of things, we have
  • enzymes from the CYP cascade, which are among other involved in the clearance of estrogen, and other hormone like substances and the metabolism of drugs,
  • MAPK and JNK, which exert anti-catabolic effects on muscle tissue, or 
  • GPX and SOD, two of the major enzymes involved in the antioxidant defenses
Now, if we take a look at all these, you may remember that low COX-2 levels have only recently been identified with profound overtraining (cf. "Overtraining inflammation insufficient repair"), that AKT (not mentioned above, but in figure 1) is one of the driving forces of skeletal muscle anabolism and telomerase, extends cell life in general, not just in cancer cells. Which brings us back to the issue of ...

...how much anti-oxidants do we actually need?

Figure 2: Total tocopherol and tocotrienol content of high vitamin E foods / oils (top) and tocopherol ratios (bottom) , data based on Whittle. 1967 and Slover. 1971
Or, in this particular case, how much tocotrienols are still beneficial? Neither I, nor anybody else knows the exact answer to this question. And against this fact, the recommendations I came across on the website of a major producer of respective supplements, which state that you would need
  • 80g of palm oilen (cooking oil),
  • 160g of rice bran oil,
  • 3kg of barley,
  • 1.5kg of wheatgerm, or 
  • 4kg of oats
to (I quote) "achieve the required [my emphasis] level of tocotrienols" should tell any reasonable person that those "required" levels (~150mg) are probably required to generate the target revenue of the said company, yet probably not required for you or any other human being to thrive.

Do not stack one more, but take one out!

Instead of adding another overpriced (and probably overdosed) tocotrienol supplement to your regimen, it is thus probably wiser to simply drop any superflous and potentially harmful alpha-tocopherol only supplements which do would offset the alpha- to gamma- and delta- tocopherol ratio (this could potentially be ameliorated by taking a natural blend) and limit the total tocopherol intake to reasonable levels, as the latter has also been shown to hamper the absorption and retention of tocotrienols (Ikeda. 2003). In this context it is also noteworthy that Ping Tou Gee writes in a 2011 paper with the aptly chosen title "Unleashing the untold and misunderstood observations on vitamin E" that this fact alone would suggest that "there is a need to review critically on the dietary reference intakes recommendations" for alpha tocopherol (α-T). His bold statement that
[i]t is not known whether α-T is still essential to humans in long terms, α-T3 [alpha tocotrienol] diet appeared to produce healthy rats over five generations.
is yet probably an attribution to Palm Nutraceuticals Sdn. Bhd. (which is not the aforementioned company which wants to force-feed you either their supplements or 2 cups of rice bran oil), of which he states in the acknowledgments that he thanks them "for permission to publish this paper" and further evidence for how pathetic parts of the research in the medical field is - awful this science business, isn't it?

References:
    1. Aggarwal BB, Sundaram C, Prasad S, Kannappan R. Tocotrienols, the vitamin E of the 21st century: its potential against cancer and other chronic diseases. Biochem Pharmacol. 2010 Dec 1;80(11):1613-31. Epub 2010 Aug 7.
    2. Ahmad NS, Khalid BA, Luke DA, Ima Nirwana S. Tocotrienol offers better protection than tocopherol from free radical-induced damage of rat bone. Clin Exp Pharmacol Physiol 2005;32:761–770 
    3. Gee PT. Unleashing the untold and misunderstood observations on vitamin E. Genes Nutr. 2011 Feb;6(1):5-16. Epub 2010 Jul 20.
    4. Ikeda S, Tohyama T, Yoshimura H, Hamamura K, Abe K, Yamashita K. Dietary alpha-tocopherol decreases alpha-tocotrienol but not gamma-tocotrienol concentration in rats. J Nutr. 2003 Feb;133(2):428-34.
    5. Kato A, Yamaoka M, Tanaka A, Komiyama Ka, Umezawa I. Physiological effect of tocotrienol. J
      Japan Oil Chem Soc (Yukugaku) 1985;34:375–376.
    6. Khanna S, Roy S, Ryu H, Bahadduri P, Swaan PW, Ratan RR, et al. Molecular basis of vitamin E
      action: tocotrienol modulates 12-lipoxygenase, a key mediator of glutamate-induced
      neurodegeneration. J Biol Chem 2003;278:43508–43515.
    7. Kobayashi H, Kanno C, Yamauchi K, Tsugo T. Identification of alpha-, beta-, gamma-, and delta-
      tocopherols and their contents in human milk. Biochim Biophys Acta 1975;380:282–290.
    8. Kuhad A, Chopra K. Attenuation of diabetic nephropathy by tocotrienol: involvement of NFkB
      signaling pathway. Life Sci 2009;84:296–301.
    9. Lee SP, Mar GY, Ng LT. Effects of tocotrienol-rich fraction on exercise endurance capacity and
      oxidative stress in forced swimming rats. Eur J Appl Physiol 2009;107:587–595.
    10. Mishra GD, Malik NS, Paul AA, Wadsworth ME, Bolton-Smith C. Childhood and adult dietary vitamin E intake and cardiovascular risk factors in mid-life in the 1946 British Birth Cohort. Eur J Clin Nutr. 2003 Nov;57(11):1418-25.
    11. Newaz MA, Nawal NN. Effect of gamma-tocotrienol on blood pressure, lipid peroxidation and total antioxidant status in spontaneously hypertensive rats (SHR). Clin Exp Hypertens 1999;21:1297–1313.
    12. Patel V, Rink C, Gordillo GM, Khanna S, Gnyawali U, Roy S, Shneker B, Ganesh K, Phillips G, More JL, Sarkar A, Kirkpatrick R, Elkhammas EA, Klatte E, Miller M, Firstenberg MS, Chiocca EA, Nesaretnam K, Sen CK. Oral tocotrienols are transported to human tissues and delay the progression of the model for end-stage liver disease score in patients. J Nutr. 2013 Mar;142(3):513-9. Epub 2013 Feb 1. 
    13. Qureshi AA, Burger WC, Peterson DM, Elson CE. The structure of an inhibitor of cholesterol biosynthesis isolated from barley. J Biol Chem. 1986 Aug 15;261(23):10544-50.
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    19. Tan B. Tocotrienols: The New Vitamin E. Spacedoc.net. http://www.spacedoc.com/tocotrienols
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    24. Yu FL, Gapor A, Bender W. Evidence for the preventive effect of the polyunsaturated phytolside chain in tocotrienols on 17beta-estradiol epoxidation. Cancer Detect Prev. 2005;29(4):383-8.