Monday, February 18, 2008

Unbalanced Fox news report misleads about vitamin-mineral safety

Unbalanced Fox news report misleads about vitamin-mineral safety By Neil E. Levin, CCN, DANLA I watched the special health report on vitamins and minerals on FOX-32 (How Do Vitamins and Minerals Really Affect Your Body? on 2/12/08, see link below), but was disappointed that the report exaggerated the risks of vitamins and minerals and minimized their benefits without any mention of the common deficiencies that exist in the American population. For example, the report cautioned about vitamin E causing blood thinning, but the Food and Nutrition Board of the Institute of Medicine has set an upper tolerable intake level (UL) for vitamin E (alpha-tocopherol) at 1,500 IU per day, which “is the highest dose unlikely to result in bleeding problems;” though the Institute has also said that the danger of the vitamin inhibiting clotting was not convincing. In other words, taking about four times the most common strength of even a hi-potency vitamin E capsule might be a problem in terms of affecting clotting, but this potency is higher than is available as a dietary supplement and one that people are unlikely to try without specific medical advice. Yet, somehow, the far more common danger of a vitamin E deficiency was completely ignored. This, despite the fact that, according to dietary data from the National Health and Nutrition Examination Surveys, ninety percent or more of the adults studied had usual intakes below the current Estimated Average Requirement. Why is a theoretical overdose problem even mentioned in the report, especially with no balancing mention of known deficiencies and benefits? What happened to fair and balanced reporting? And what are the benefits of vitamin E supplementation? An NIH-supported USDA -Tufts University study published in the medical journal JAMA reported, “…we observed a protective effect of vitamin E supplementation on upper respiratory tract infections, particularly the common cold,” for nursing home patients taking 200 IU of vitamin E daily. And Annals of the New York Academy of Sciences reported that, “The results of this clinical trial show that vitamin E supplementation significantly reduces the incidence rate of common colds and the number of subjects who acquire a cold among elderly nursing home residents.” Zinc was also mentioned in the FOX report as a possible overdose candidate, but levels required to reach the negative side effects mentioned are between 150-450 mg per day, again requiring a consumer to take several capsules to achieve this. The highest potency I have ever seen (in 35 years) was 75 mg, though 15-50 mg products are relatively common. Yet the median intake among American adults is just over 2/3 of the Daily Value, making deficiencies far more common than overdoses. Again, the FOX report ignored the common, greater danger in favor of sensationalizing a remote possibility of overdosing. Zinc is essential for many biochemical reactions in the body, and is most notably associated with immune function and wound healing. Yet isn’t FOX essentially warning people against taking zinc, hinting that they may be in danger but without any hint of the true risks and benefits? A dietician in the report stated that there is no proof that taking extra vitamin C shortens or prevents colds. That should come as news to the researchers at the University of Pittsburgh Medical Center. Publishing results of a Review Study in the medical journal American Family Physician in February 2007, these physicians reported that, “Thirty trials involving 9,676 cold episodes showed a statistically significant decrease in illness duration with vitamin C taken before onset of symptoms…. Likewise, 15 trials involving 7,045 cold episodes demonstrated a decrease in severity scores and in days confined to the home.” While there is some little evidence (not none) that vitamin C can prevent the incidence of colds, there is significant evidence that it can shorten the duration and severity of colds. Don’t you think that the FOX report is irresponsible by highlighting rare nutrient overdoses while ignoring common deficiencies? Also, why would one person’s opinion that vitamin C is worthless against colds trump the collective evidence of 30 clinical studies that met the strict criteria of a review study? Given these gross errors, I suggest that FOX assigns fact-checkers to review all medical and health reports. Let’s put an end to the flawed practice of naively taking the word of health professionals who appear not be up-to-date on what’s published in the medical literature. This is most important when demonstrably false blanket statements are made that inappropriately dismiss the safety and efficacy of essential nutrients that are known to be deficient in most Americans’ diets. REFERENCES:;jsessionid=BF06BF0BCA71AE327C05A6BA65DEB517?contentId=5757535&version=2&locale=EN-US&layoutCode=VSTY&pageId=1.1.1&sflg=1 Vitamin E Fact Sheet NIH Office of Dietary Supplements Zinc Fact Sheet NIH Office of Dietary Supplements “Thirty trials involving 9,676 cold episodes showed a statistically significant decrease in illness duration with vitamin C taken before onset of symptoms: an 8 percent decrease (95% confidence interval [CI], 3 to 13 percent) in adults and a 13.5 percent decrease (95% CI, 5 to 21 percent) in children. Likewise, 15 trials involving 7,045 cold episodes demonstrated a decrease in severity scores and in days confined to the home. Vitamin C did not decrease the incidence of cold in the general population. However, a subgroup of six trials involving runners, skiers, and soldiers participating in subarctic exercises demonstrated a 50 percent relative reduction in the risk of developing a cold (95% CI, 32 to 62 percent).” Simasek M, Blandino DA. Treatment of the common cold. Am Fam Physician. 2007 Feb 15;75(4):515-20. Review. PMID: 17323712 [PubMed - indexed for MEDLINE]. Hathcock JN, et al. Vitamins E and C are safe across a broad range of intakes. Am J Clin Nutr. 2005 Apr;81(4):736-45. Review. PMID: 15817846 [PubMed - indexed for MEDLINE] Dial S, Eitenmiller RR. 1995. Tocopherols and tocotrienols in key foods in the U.S. diet. In: Ong ASH, Niki E, Packer L, eds. Nutrition, Lipids, Health, and Disease. Champaign, IL: AOCS Press. Pp. 327–342. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids (2000). Institute of Medicine JASPREET K.C. AHUJA, JOSEPH D. GOLDMAN, and ALANNA J. MOSHFEGH. Current Status of Vitamin E Nutriture. Ann NY Acad Sci 2004 1031: 387-390. Erwin RB, et al. Dietary intake of selected minerals for the United States population: 1999-2000. Adv Data. 2004 Apr 27;(341):1-5. PMID: 15114720 [PubMed - indexed for MEDLINE] Meydani SN, et al. Vitamin E and respiratory tract infections in elderly nursing home residents: a randomized controlled trial. JAMA. 2004 Aug 18;292(7):828-36. Erratum in: JAMA. 2004 Sep 15;292(11):1305. JAMA. 2007 May 2;297(17):1882. PMID: 15315997 [PubMed - indexed for MEDLINE] Meydani SN, Han SN, Hamer DH. Vitamin E and respiratory infection in the elderly. Ann N Y Acad Sci. 2004 Dec;1031:214-22. Review. PMID: 15753147 [PubMed - indexed for MEDLINE]

1 comment:

Bobber said...

This page at the Linus Pauling institute mentions a Japanese study done in 2006. This was a 6 year study and it found a 66% reduction in the number of colds contracted.