I finally had a chance to read the article by Paul Offit. What a magnificent piece of propaganda for the pharmaceutical industry! This is an industry whose “rigorously tested and FDA-approved” products have killed and maimed thousands of people – remember thalidomide, Vioxx and Baycol??
This article and others like it attacking the supplement industry and praising the pharmaceutical industry are becoming more and more frequent and, apart from raising obvious concerns about conflicts of interest, also raises the question: “Are medical doctors qualified to do research in the field of supplements?” The answer, with a few exceptions, is clearly “NO”. Knowledge of anatomy, pharmacology and the ability to diagnose disease and write prescriptions are about as useful as astronomy and English literature when it comes to understanding the intricacies of vitamins and other supplements. Here a solid grounding in organic chemistry, biochemistry and physical chemistry and a good knowledge in the field of nutrition is needed, and current medical education simply does not provide that.
As Jackie so aptly points out, most of the studies on supplements carried out by mainstream medical researchers are poorly designed and executed and results are often improperly interpreted. It is also obvious that many studies are designed to produce negative or null results and thus support the myth that all supplements are useless or dangerous or both and that taking them just “produces expensive urine” or some other catchy phrase. The design of these “doomed to fail” studies may be intentional or simply due to ignorance and often involve the use of an ineffective dose or form of a vitamin or other supplement.
A typical example of this is the SELECT trial evaluating the use of selenium and vitamin E in the prevention of prostate cancer. During the design phase of this trial the choice of the type of vitamin E to use was discussed in some detail and it was decided to use synthetic alpha-tocopheryl acetate even though the Steering Committee agreed that natural alpha-tocopherol or gamma-tocopherol would likely be far more effective. Why put 32,000 men through a lengthy and costly trial knowing that one of the components of the intervention was inferior?(1)
It is, unfortunately, difficult and time-consuming to check the claims made by Dr. Offit in his tirade as he, most unscientifically, does not substantiate them with references to the studies he is quoting. However, I can comment on two studies involving patients at elevated risk for lung cancer. The study involving 29,000 male, Finnish smokers carried out by the National Cancer Institute and Finland’s National Public Health Institute (ATCB trial) and the study involving 18,000 patients with an elevated risk of lung cancer (CARET trial) carried out by researchers at the Fred Hutchinson Cancer Research Center in Seattle (2-4).
My comments on these two studies are summarized in my report “Beta-carotene: Friend or Foe” which you can access here: [
www.yourhealthbase.com]
I would urge you to read this report just to get a feel for the intricacies involved in supplement research.
To summarize the findings of my report:
Supplementing with excessive amounts of synthetic beta-carotene in isolation is of no benefit and may be harmful, especially for smokers.
• All the trials used synthetic beta-carotene which is almost 100%
trans-beta-carotene. Although
trans-beta-carotene is well absorbed and readily converted to vitamin A, it does have a serious drawback. Intake of beta-carotene in isolation markedly lowers the concentration of lycopene in the blood; this effect is particularly significant in the case of
trans-beta-carotene(5,6). Since lycopene is the most active fat-soluble antioxidant in human blood (even more active than vitamin E), a reduction of 25% or more in its concentration could have serious consequences. It is worth noting that at least one experiment has shown that supplements containing beta-carotene from natural sources do not cause a statistically significant drop in lycopene concentration(5).
• The average dietary intake of beta-carotene is somewhere between 2 and 5 milligram per day, yet one of the studies added 30 mg/day of synthetic supplement; this caused the beta-carotene level in the blood to rise by a factor of 10 or more (a 1000% increase). Little is known about the effect of such abnormally high levels but they could conceivably be toxic over the long term and almost certainly will cause serious imbalances in the concentration of other important carotenes(7,8).
• Beta-carotene shows its greatest activity as an antioxidant at low partial pressures (tension) of oxygen such as found in blood vessels and most inner organs of the body(9,10). It is not effective at higher oxygen tensions such as would be found in the lungs. Some researchers believe that beta-carotene acts as a pro-oxidant at higher oxygen tensions(8,9). This effect is especially strong at high beta-carotene concentrations(9). Considering that beta-carotene concentrations in several of the studies were ten times the normal level it is conceivable that the pro-oxidant effect could have been magnified to such an extent that it contributed significantly to the initiation of lung cancer.
It is indeed unfortunate that the synthetic, most ineffective versions of vitamin E and beta-carotene were picked for the trials discussed above. Had natural gamma-tocopherol and natural beta-carotene been evaluated instead the results might have been quite different, especially in light of recent findings that high blood levels of gamma-tocopherol are associated with a substantially reduced risk of prostate cancer (11). Unfortunately, the conclusion that vitamin E and beta-carotene are useless in cancer prevention is by now so firmly entrenched in medical lore that it is unlikely that the SELECT, ATCB, and CARET trials will ever be repeated using effective forms of vitamin E and beta-carotene.
Not surprisingly, Dr. Offit completely fails to mention any of the numerous studies that have found vitamins to be beneficial such as:
The study carried out by researchers at the Centers for Disease Control and Prevention involving 450,000 men and 610,000 women who were followed from 1982 to 1989. This study concluded that participants who supplemented with multivitamins and antioxidants (vitamins A, C or E) had a 15% lower risk of dying from heart disease or cancer than did participants who took only multivitamins or no vitamins at all(12).
The 2004 study carried out by a group of distinguished medical researchers from 4 US universities which concluded that supplementation with vitamins C and E reduces the risk of developing Alzheimer’s disease by 78% (13).
The Harvard Medical School study that found that women with a daily intake of vitamin C between 240 and 360 mg/day (from diet and supplements) have a 66% lower risk of developing cataracts than do women with an intake of less than 140 mg/day(14).
Evidence that vitamin E can prevent and reverse heart disease is now incontrovertible. In 1992 researchers at the University of Texas reported that vitamin E protects against atherosclerosis (hardening of the arteries) by preventing oxidation of the low-density lipoprotein fraction of blood (15). In 1993 researchers at the Harvard Medical School released a study showing that vitamin E supplementation prevents heart disease. Nurses who took more than 100 IU/day of vitamin E for more than two years reduced their risk of heart disease by 41%. A related study involving almost 40,000 male health professionals showed that men who supplemented with between 100 and 250 IU/day reduced their risk of heart disease by 37%. Vitamin E is also highly beneficial in the treatment of intermittent claudication and recent research has confirmed its ability to prevent and, in some cases, reverse the progression of atherosclerosis(16-20).
Vitamin E is also highly effective in warding off a heart attack. Researchers at Cambridge University in England reported in 1996 that patients who had been diagnosed with coronary atherosclerosis could lower their risk of having a heart attack by 77% per cent by supplementing with 400 IU or 800 IU/day of natural source vitamin E(21). Researchers at the Toyama Medical University in Japan have reported that patients with unstable angina can reduce their risk of angina attacks by a factor of six by supplementing with vitamin E (300 mg/day of alpha-tocopherol acetate)(22). Supplementation with vitamin E has also been found useful in preventing complications after heart surgery and helps slow the restenosis (reblockage) of arteries subjected to angioplasty(18,19,23). More recently, researchers at the Harvard Medical School reported that supplementing with a combination of vitamin E and vitamin C reduced stroke risk in women by 31% (24).
And the list goes on [
www.yourhealthbase.com]
So who is this Dr. Offit anyway? He is a pediatrician who strongly pushes childhood vaccines as a paid consultant to Merck, a major manufacturer of such vaccines. Does this qualify him for writing a book discussing the merit or lack thereof of vitamins and other supplements? You be the judge! In any case, Dr. Offit would seem to be a very controversial individual who is not a stranger to making unsubstantiated claims. [
www.naturalnews.com] and [
www.ocregister.com]
REFERENCES
1. Lippman, SM, et al. Designing the Selenium and Vitamin E Cancer Prevention Trial (SELECT). Journal of the National Cancer Institute, Vol. 97, January 19, 2005, pp.94-102.
2. Albanes, D, et al. Effects of alpha-tocopherol and beta-carotene supplements on cancer incidence in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study. American Journal of Clinical Nutrition, 1995 Dec;62 (6 Suppl): 1427S-1430S.
3. Albanes, D, et al. Alpha-Tocopherol and beta-carotene supplements and lung cancer incidence in the alpha-tocopherol, beta-carotene cancer prevention study: effects of base-line characteristics and study compliance. Journal of the National Cancer Institute, 1996 Nov6:88(21); 1560-70.
4. Omenn, Gilbert S., et al. Effects of a combination of beta carotene and vitamin A on lung cancer and cardiovascular disease. The New England Journal of Medicine, Vol. 334, May 2, 1996, pp. 1150-55.
5. Gaziano, J. Michael, et al. Discrimination in absorption or transport of beta- carotene isomers after oral supplementation with either all-trans- or 9-cis-beta-carotene. American Journal of Clinical Nutrition, Vol. 61, 1995, pp. 1248-52
6. Micozzi, Marc S., et al. Plasma carotenoid response to chronic intake of selected foods and beta-carotene supplements in men. American Journal of Clinical Nutrition, Vol. 55, No. 6, June 1992, pp. 1120-25.
7. Omenn, Gilbert S., et al. Effects of a combination of beta carotene and vitamin A on lung cancer and cardiovascular disease. The New England Journal of Medicine, Vol. 334, May 2, 1996, pp. 1150-55.
8. Woodall, Alan A., et al. Caution with beta-carotene supplements. The Lancet, Vol. 347, April 6, 1996, pp. 967-68.
9. Burton, G.W. and Ingold, K.U. Beta-carotene: an unusual type of lipid antioxidant. Science, Vol. 224, May 11, 1984, pp. 569-73.
10. Frei, Balz. Reactive oxygen species and antioxidant vitamins: mechanisms of action. American Journal of Medicine, Vol. 97 (suppl 3A), September 26, 1994, pp. 5S-13S.
11. Huang, Han Yao, Prospective study of antioxidantmicronutrients in the blood and the risk of developing prostate cancer. American Journal of Epidemiology, Vol. 157, February 15, 2003, pp.335-44.
12. Watkins, Margaret L., et al. Multivitamin use and mortality in a large prospective study. American Journal of Epidemiology, Vol. 152, July 15, 2000, pp. 149-62.
13. Zandi, PP, et al. Reduced risk of Alzheimer’s disease in users of antioxidant supplements. Archives of Neurology , Vol. 61, January 2004, pp.82-88.
14. Jacques, Paul F., et al. Long-term nutrient intake and early age-related nuclear lens opacities. Archives of Opthalmology, Vol. 119, July 2001, pp.1009-19.
15. Jialal, Ishwarlal and Grundy, Scott M. Effect of dietary supplementation with alpha- tocopherol on the oxidative modification of low-density lipoprotein. Journal of Lipid Research, Vol. 33, June 1992, pp. 899-906
16. Azen, Stanley P., et al. Effect of supplementary antioxidant vitamin intake on carotid arterial wall intima-media thickness in a controlled clinical trial of cholesterol lowering. Circulation, Vol. 94, No. 10, November 15, 1996, pp. 2369-72.
17. Stampfer, Meir J., et al. Vitamin E consumption and the risk of coronary disease in women and men. New England Journal of Medicine, Vol. 328, No. 20, May 20, 1993, pp. 1444-56.
18. Stampfer, Meir J. and Rimm, Eric B. Epidemiologic evidence for vitamin E in prevention of cardiovascular disease. American Journal of Clinical Nutrition, Vol. 62, December 1995, pp. 1365S-69S.
19. Hodis, Howard N., et al. Serial coronary angiographic evidence that antioxidant vitamin intake reduces progression of coronary artery atherosclerosis. Journal of the American Medical Association, Vol. 273, No. 23, June 21, 1995, pp. 1849-54.
20. Paolisso, Giuseppe, et al. Chronic intake of pharmacological doses of vitamin E might be useful in the therapy of elderly patients with coronary heart disease. American Journal of Clinical Nutrition, Vol. 61, 1995, pp. 848-5216.
21. Stephens, Nigel G., et al. Randomised controlled trial of vitamin E in patients with coronary disease: Cambridge Heart Antioxidant Study (CHAOS). The Lancet, Vol. 347, March 23, 1996, pp. 781-86.
22. Miwa, Kunihisa, et al. Vitamin E deficiency in variant angina. Circulation, Vol. 94, No. 1, July 1, 1996, pp. 14-18.
23. Meydani, Mohsen. Vitamin E. The Lancet, Vol. 345, January 21, 1995, pp. 170-75.
24. Cook, NR. Et al. A randomized trial of vitamins C and E and beta carotene in the secondary prevention of cardiovascular events in women. Archives of Internal Medicine, Vol. 167, August 13/27, 2007, pp. 1610-18.
Hans
Edited 1 time(s). Last edit at 06/13/2013 08:21PM by Hans Larsen.