Tuesday, November 30, 2010

U.S. Increases Recommendations for Vitamin D Intake but Misses the Mark

U.S. Increases Recommendations for Vitamin D Intake but Misses the Mark

As you probably know from news reports, the recommendations for individual consumption of vitamin D has now increased, as has the tolerable Upper Limit (UL) that indicates a higher intake level at which the vast majority of people will not suffer any unpleasant side effects. But these recommendations are controversial for being too conservative, and at the same time the report has been sensationalized in the popular media with an inappropriate emphasis on possible side effects of megadoses.

The Institute of Medicine (IOM), the health arm of the National Academy of Sciences, is an independent, nonprofit organization that works outside of government to provide unbiased and authoritative advice to decision makers and the public. Through more than three dozen sets of guidelines, known as Dietary Reference Intakes (DRIs), IOM provides estimates of the amounts of nutrients that individuals need to consume each day. Health care professionals and policy makers, including federal nutrition officials who develop nutrition programs as well as the food industry, rely on this guidance from the IOM. The reference numbers that you see on food and dietary supplement labels, such as Daily Values (DV), DRIs, and Recommended Daily Allowances (RDAs), are generated by IOM. (1) These values are also utilized by some foreign governments as authoritative references on which to base their own food and supplement regulations.

The good news is that, in a report issued by IOM on November 30, 2010, the RDA has now increased by 50% (from 400 IU to 600 IU) and the tolerable Upper Limit has now doubled (from 2,000 IU to 4,000 IU). Also, the RDA for adults over 71 years old has increased to 800 IU daily. (2) This means that the new recommendations are often higher than the 400 IU that is found in a typical multivitamin or calcium+D formula, thus requiring additional supplementation to meet the RDA. And the leeway for safe use at the upper end is now double what it was before, making such supplementation at higher levels still within a margin generally accepted as safe; at least up to 4,000 IU, though as usual that number is deliberately set low and has a large safety margin.

IOM’s report stating that most Americans have adequate circulating levels of vitamin D is somewhat controversial, as it utilizes a standard of 20 ng/mL (equivalent to a measure of 50 nmol/L) (3) that is not universally accepted as adequate for optimal health by many modern vitamin D researchers. While that amount may adequately support bone health, which was (as usual) the primary focus of the IOM committee, there are vitamin D receptors on many other human cells and this vitamin reportedly plays an important role in cardiovascular disease (4), immune health (5), prostate and breast health (7), blood sugar metabolism (6), cancer prevention (7,8) , and a host of natural processes. One recent report stated that, “The desirable serum 25 (OH) D levels is at least 100 nmol/L, a level that has generally been found to provide most of the health benefits of vitamin D.” (9) This recommendation is twice as high as the new RDA, evidencing the controversial nature of IOM’s RDA process.

However, the IOM committee admittedly based its recommendations solely on vitamin D’s effects on bone health after reviewing numerous studies on other benefits and concluding that more study is required to generate the level of evidence that IOM requires to set its recommendations. Committee chair Catharine Ross was quoted as saying, “Amounts higher than those specified in this report are not necessary to maintain bone health.” (10) As the amount of science in these other areas grows, so should the levels recommended for general health. But statements such as that by Dr. Ross that “people don't need more than the amounts established in this report” refer only to bone health and should not be construed as denying the fact that other benefits at higher levels of intake have been reported, though not as consistently as the IOM committee would need to accept them as conclusive enough to revise its recommended levels upward.

Based on current research, natural health advocates typically recommend levels 50-100% higher than the IOM report recommends in order for people to obtain the full protective benefits of vitamin D, and many physicians who test for this vitamin ask their patients to meet or exceed that higher level. This is perhaps the most controversial part of the report, and I predict that a barrage of higher numbers appearing in medical reports as protective will force another overdue round of RDA changes in perhaps another 10-15 years. In my opinion, the IOM is always behind the times in the area of nutrient recommendations, being by nature super cautious. We dared to hope, but nobody really expected the IOM panel to accept the evidence of recent published review studies in medical journals and raise both the RDA and UL to the recommended five times their previous levels, and frankly we were not surprised that they didn't. These special panels are typically very conservative and hesitant to make dramatic changes, and are comprised with well-qualified general nutrition experts but not with experts in the particular area in question who might push for acceptance of higher levels.

People have already been taking over 2,000 IU daily, the old tolerable Upper Limit, without apparent harm and will probably continue to take over the new 4,000 IU UL as well. Clinical science indicates that higher levels are still quite safe, at least up to 10,000 IU daily for most adults. In 2007 a review published in the American Journal of Clinical Nutrition applied the same risk assessment methodology used by the Food and Nutrition Board (FNB) to derive a proposed revision of the safe Tolerable Upper Intake Level (UL) for vitamin D. (11) Noting an absence of toxicity in trials conducted in healthy adults that used a vitamin D dose ≥250 µg/d (up to 10,000 IU of vitamin D3), a new UL of 10,000 IU was confidently proposed, but was apparently not accepted by the IOM. Nor was the recommendation for a new RDA to be raised to 2,000 IU.

In fact, the 10,000 IU daily UL proposal may have been conservatively low; so what does that make the revised tolerable UL of only 4,000 IU? According to a report in the journal Nutrition Reviews, "The input needed for efficacy, in addition to typical food and cutaneous [sunlight] inputs, will usually be 1000-2000 IU/day of supplemental cholecalciferol [vitamin D3]. Toxicity is associated only with excessive supplemental intake (usually well above 20,000 IU/day)." (12) [Italicized words added for clarity]

Dietary supplement manufacturers already were not allowed to make disease claims on dietary supplements without (always reluctant) FDA approval, so the IOM’s report that vitamin D has not been proven to prevent various diseases is not news for them. However, consumers will continue to be exposed to positive reports on the vitamin and most will understand that just because it has not yet been "proven" to prevent certain diseases doesn't mean that it doesn't, especially at levels higher than needed purely for bone health, nor does it suggest that there is no supporting evidence that it still may be an important preventative factor.

The government standard of proof in the dietary supplement area has been frequently criticized and the FDA in fact has lost several federal court cases, where courts have ordered the agency to comply with the law allowing such claims where substantial evidence already exists for some supplements’ role in disease prevention (for example, selenium and cancer). (13,14) Of course, almost never is anything "proven" in a scientific field; theories rule most scientific endeavors. But that should not suffice to allow the government to muzzle legitimate science nor to prevent the public from taking natural nutrients at levels that they may require due to their own individual biochemistry and relevant environmental factors. In this case, the new RDA and UL are simply baby steps in the right direction, but perhaps the full knowledge of vitamin D’s health benefits is still in its infancy.

REFERENCES:

  1. http://www.iom.edu/About-IOM.aspx Accessed November 30, 2010
  2. Dietary Reference Intakes for Calcium and Vitamin D. Food and Nutrition Board, Institute of Medicine, National Academies. Released: November 30, 2010
  3. http://ods.od.nih.gov/factsheets/VitaminD-Consumer/ Accessed November 30, 2010
  4. Wallis DE, Penckofer S, Sizemore GW. The "sunshine deficit" and cardiovascular disease. Circulation. 2008 Sep 30;118(14):1476-85. Review. Erratum in: Circulation. 2009 Jun 2;119(21):e550. PubMed PMID: 18824654.
  5. Cannell JJ, Zasloff M, Garland CF, Scragg R, Giovannucci E. On the epidemiology of influenza. Virol J. 2008 Feb 25;5:29. Review. PubMed PMID: 18298852; PubMed Central PMCID: PMC2279112.
  6. de Boer IH. Vitamin D and glucose metabolism in chronic kidney disease. Curr Opin Nephrol Hypertens. 2008 Nov;17(6):566-72. Review. PubMed PMID: 18941348; PubMed Central PMCID: PMC2882033.
  7. Skinner HG, Michaud DS, Giovannucci E, Willett WC, Colditz GA, Fuchs CS. Vitamin D intake and the risk for pancreatic cancer in two cohort studies. Cancer Epidemiol Biomarkers Prev. 2006 Sep;15(9):1688-95. PubMed PMID: 16985031.
  8. Garland CF, Garland FC, Gorham ED, Lipkin M, Newmark H, Mohr SB, Holick MF. The role of vitamin D in cancer prevention. Am J Public Health. 2006 Feb;96(2):252-61. Epub 2005 Dec 27. Review. PubMed PMID: 16380576; PubMed Central PMCID: PMC1470481.
  9. Grant WB, Schwalfenberg GK, Genuis SJ, Whiting SJ. An estimate of the economic burden and premature deaths due to vitamin D deficiency in Canada. Mol Nutr Food Res. 2010 Aug;54(8):1172-81. PubMed PMID: 20352622.
  10. http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=13050 Accessed November 30, 2010
  11. Hathcock JN, Shao A, Vieth R, Heaney R. Risk assessment for vitamin D. Am J Clin Nutr. 2007 Jan;85(1):6-18. Review. PubMed PMID: 17209171.
  12. Heaney RP. Vitamin D: criteria for safety and efficacy. Nutr Rev. 2008. Oct;66(10 Suppl 2):S178-81. Review. PubMed PMID: 18844846.
  13. http://www.emord.com/FDA_Agrees_to_Allow_Selenium_Qualified_Health_Claims.html Accessed November 30, 2010
  14. http://www.kelleydrye.com/publications/client_advisories/0576 Accessed November 30, 2010

Saturday, November 20, 2010

Bitter Orange Safety Concerns Are Overblown: study

A review of bitter orange safety was published in a peerr-reviewed journal. Analyzing the adverse event reports (AERs) submitted to the FDA, Sidney J. Stohs, dean emeritus of the Creighton University School of Pharmacy and Health Professions, reported that, “The belief that p-synephrine exerts serious cardiovascular and other events continues to be believed by the lay public as well as healthcare professionals, in spite of the lack of clearly defined supportive evidence for this supposition, as well as extensive evidence to the contrary.”



"An 8 oz glass of Californian mandarin orange juice may contain up to 35 mg p-synephrine (USDA). A sweet orange typically contains about 6 mg p-synephrine."


http://www.nutraingredients-usa.com/Industry/Bitter-orange-concerns-unwarranted-and-unjustified-Review/?c=Fe5usULeGc2A9I8d6ljtPw%3D%3D&utm_source=newsletter_daily&utm_medium=email&utm_campaign=Newsletter%2BDaily

Source: Journal of Functional Foods. Published online ahead of print, doi: 10.1016/j.jff.2010.10.003
“Assessment of the adverse event reports associated with Citrus aurantium (bitter orange) from April 2004 to October 2009” Author: S.J. Stohs

Thursday, November 11, 2010

Cholesterol measures

Total cholesterol means nothing in terms of health. Just as many people have fatal heart attacks with low total cholesterol as high, and there are additional health risks if it is too low. Flipping a coin gives you just as good data. I have seen people whose total cholesterol is high but who seem to have little risk. There may also be a genetic component to the baseline total cholesterol number that defies easy changes.


The main relevant and meaningful cholesterol number today is the ratio of total cholesterol to HDL cholesterol (over 5 is not good; lower means lower risk). This means that, if you have high total cholesterol but your ratio is good, your HDL number is high and that makes you better protected than someone whose HDL is low. Routine blood screenings now tend to include this important number. Homocysteine is another number that indicates your risk of inflammatory conditions affecting the brain and cardiovascular system.

Wednesday, November 03, 2010

Women's Health Interview, October 2010

Women’s biggest health challenges tend to be related to three general areas: hormonal health (including PMS and menopause issues), pregnancy, and maintaining health as they age (bone health and avoiding chronic degenerative conditions).

Women do seem to suffer more from certain problems related to inflammatory challenges and hormonal changes. Because of their regular, or sometimes irregular hormonal cycles, there are both advantages and disadvantages compared with men; at least until menopause tends to even the field regarding heart disease, for example. Regular menstruation lowers iron stores, reducing health problems related to oxidative and microbial challenges from free radicals that can be elevated due to the actions of uncontrolled free iron. Because of this, premenopausal women tend to have lower levels of heart disease than either post-menopausal women or adult men.

Also, because of their greater reliance on three major forms of natural estrogen as a dominant hormone complex, women seem to have greater risks of getting hormonal abnormalities and elevated cancer rates related to breast, endometrial tissues, etc. There are numerous factors involved, but oxidation of estrogens into more dangerous forms has been suggested as a major contributor to those risks. The fact that certain volatile plastics containing free BPA and specific other chemicals are known to be strong estrogen mimics makes exposure to those substances very dangerous to women, in particular.

Men do share some of those risks; for example, some estrogenic agricultural chemicals widely used on lawns, golf courses, and farms (herbicides, pesticides) are suggested to elevate the risk of prostate abnormalities. But men’s consequences tend to be more subtle and drawn out than the very real risks that women face from both these exposures and lack of protective nutrients such as a range of antioxidants and detoxification aids such as silymarin, broccoli and cruciferous vegetable consumption, and various liver supporting herbs and nutrients. The regular use of NSAID anti-inflammatory drugs – often utilized for PMS and other aches and pains – is associated with side effects that similar-acting nutrients and herbs lack: negative effects include reducing availability of some important nutrients, upregulation of pain triggers, negative effects on mood, stomach and GI problems, and degenerative cascades. Bless their hearts; many women don’t have it easy.

Women who eat enough legumes, flax seeds, and other sources of plant estrogens (phytoestrogens) tend to have more manageable menstrual cycles. Certain signs, like menstrual-related migraine headaches, indicate a deficiency of adequate natural progesterone levels that can be helped either by supplying the herb Vitex (chaste berry) if premenopausal or by applying natural progesterone cream to the skin. Certain herbal formulas and isoflavones from foods are utilized to preserve healthy and more comfortable menstrual cycles.

One thing that women should do to prepare for menopause is to maintain their bone mass by exercise and getting adequate supplies of not only calcium but also vitamins C, D, and K, magnesium, boron, and other bone support nutrients. The value of an alkalinizing whole food diet is of primary importance. The presence in the diet of legumes and flax seeds eases the transition to menopause, which is a normal part of a women’s life cycle.

The existence of biofilms informs our understanding of areas where bacteria and microbes can gown in the body. The fact that certain organisms – helpful or harmful – can create a mass that is layered like chainmail to resist removal is a powerful visual image that aids in understanding why it takes so long to effect changes in our inner ecology. Ideally, we have friendly probiotic bacteria coating our GI and urinary tracts to crowd out undesirable organisms. In fact, it was recently discovered that the purpose of the appendix was to serve as a reservoir of such probiotics to help “reboot” the system in case of problems that kill off the good bacteria; of course, with antibiotics, high sugar diets, stress, and other factors lowering the vitality of our probiotics, some people will grow the nasty stuff in their appendixes, presenting a serious health risk. The ability of Candida albicans live yeast and other organisms to overgrow at undesirable levels at the expense of more beneficial probiotic microbes means that some of our layered biomass colonies are undesirable and difficult to remove quickly. D-Mannose and cranberry (blueberries, too) tend to help prevent the spread of these colonies by preventing undesirable particles from adhering to the urinary tract walls but don’t kill off existing colonies. Still, these natural substances are helpful in curtailing their spread while other strategies are implemented, such as low sugar intake or even pharmaceuticals.

To support breast health it is wise to avoid BPA plastics, don’t microwave food in plastic, don’t consume agricultural chemicals on food, eat a plant-based diet providing antioxidant-rich produce, and eat plenty of broccoli, cruciferous vegetables, and non-GMO legumes, especially soy.

Various experts warn us against eating soy, with the suggestion that plant estrogens are dangerous. I have investigated the scientific literature to determine the risk and found that the scientific consensus is that there is no risk for healthy women, and even no indication that soy foods are unsafe for women who have had breast cancer! That is amazing when you consider all of the negative theories being hyped on the Internet. Soy prevents oxidation and conversion of estrogen into its more dangerous forms, aids in liver metabolism of these hormones and various toxins, and has been “proven” to protect against heart disease (soy actually has an FDA-approved qualified health claim related to this benefit).


 

The Truth About Fructose Dangers

Pure crystalline fructose is an alternative natural sweetener that has long been used in the natural products industry as a common sugar substitute. Its major claim to fame is that in the short term fructose raises blood sugar far less than sucrose, the primary sugar found in white sugar that is made from sugar cane or sugar beets. Crystalline fructose should not be confused with the synthesized liquid sweetener called high fructose corn syrup (HFCS), which is made by a different process and is a mixture of roughly half fructose and half glucose (dextrose) that is widely used in the beverage and processed food industries. Unlike HFCS, fructose is a naturally occurring sugar made by plant photosynthesis that is a primary sugar in many healthy fruits. Being about 50% sweeter than sucrose, fructose can also be used more sparingly in recipes to cut their caloric intake by about 1/3.

Because of the unique challenges of formulating natural products without the use of artificial sweeteners or flavorings, sometimes a small amount of fructose is the best match for the flavorings in a product. For example, liquid vitamin B-12 has a distinct flavor profile and other sweeteners do not mask it quite as well as fructose can. Often a mixture of sweeteners may be used to create a “mouth feel” that is acceptable to consumers, who often use white sugar as their sensory standard for sweeteners. While some people may intellectually prefer other sweeteners or even white sugar, in sensory tests the fructose mixture often gets higher marks from consumers, and this leads to high compliance with recommended label uses.

I appreciate the concerns over the use of fructose. It has certainly been abused in the Western diet, especially in the form of HFCS. Americans' fructose consumption on average has tripled over the past century. But increased consumption of fruit juice and sucrose itself also are implicated in our national health decline; certainly not fructose alone, nor fructose in low doses.

According to Dr. Lustig*, an authority on fructose metabolism, human studies have not consistently shown the effect of fructose to induce insulin resistance; a negative effect reported in some animal and preliminary human studies related to altered liver metabolism. Dr. Lustig also admits that not all human studies show a negative effect of fructose on liver health or metabolic syndrome. There appear to be certain individual factors involved that make such effects somewhat idiosyncratic. Many of the studies cited are cell studies, animal studies giving high doses of fructose to mutant mice, or human studies where consumption of a lot of soft drinks were involved that provided a large number of calories comprising an unhealthy proportion (25% or more) of total daily caloric intake (about 500 calories as fructose every day). Contrast this with a healthy nutritional product that provides only a few calories, a very low percent versus those unhealthy diets!

Dr. Lustig notes that "In the hypocaloric (eg, starvation) state, fructose is as beneficial as glucose"; while also noting it has ill effects in the "hypercaloric state". He also discusses how a small amount of ethanol, a substance with similar liver effects to high fructose diets, is actually health-promoting while large amounts have the opposite effect. This reinforces that the ability of substances to elicit ill effects on the liver are typically dose dependent and require larger-than-normal amounts. In effect, 'the dose makes the poison;' as has been noted for many substances throughout history.

Dr. Lustig specifically cites three what he calls "antidotes" to the negative hepatic (liver) effects of fructose:

1. reduce the amount consumed

2. exercise

3. increase fiber intake.

So, upon reviewing these facts, the consumption of a small amount of fructose is unlikely to be harmful to the general public. Additionally, consumption of reasonable amounts may also be quite harmless if the person gets enough fiber and/or exercise. And the accepted fact that fructose does not directly raise blood glucose still gives it some short term advantages over certain other sweeteners for many people, if consumed at appropriate levels. Faster acting sugars that are higher on the Glycemic Index like glucose (which represents close to half of the sugar content of HFCS) would more immediately impact one's blood sugar, with chronic overuse eventually leading to insufficient/reduced insulin sensitivity (increased insulin resistance) that is associated with a loss of blood sugar control. Higher Glycemic sugars would affect this blood glucose control system much faster than an equivalent amount of pure fructose. And a lack of insulin sensitivity also indicates a problem in properly absorbing and recycling vitamin C in many of our body's cells; especially immune, muscle, and bone cells.

There are a variety of natural sweeteners to fit into most individuals' personalized dietary regime; but I do not promote the indiscriminate use of any sweetener, especially refined or synthetic ones. People like to have choices and will select sweeteners according to their own taste and health issues. For example, some avoid barley malt because of gluten sensitivity or certain other sweeteners because of corn allergies. People on limited diets need to scrutinize the available sweeteners and select what seems right for their own situation. But it's clear that a small amount of almost any natural sweetener, say to sweeten a cup of tea, does not seem to have any demonstrable health risk. For overly large amounts, the potential risks do increase. But a demonstrated risk level typically represents consumption of several hundred calories a day of refined sugars, including fructose, and it obviously is unwise to take in most of our daily carbohydrates in the form of refined sugars of any kind.

Consumption of small amounts of pure crystalline fructose simply doesn’t have a measureable effect on health and doesn’t need to be avoided. It’s the fructose consumed in large quantities in processed foods and beverages, where it comprises perhaps the major source of carbohydrates in the modern diet, that is the real health concern.

* Lustig RH. Fructose: metabolic, hedonic, and societal parallels with ethanol. J Am Diet Assoc. 2010 Sep;110(9):1307-21. PubMed PMID: 20800122.