Life Extension Weekly Update, June 21 2002
The June 19 2002 issue of the Journal of the American Medical Association published Scientific Review and Clinical Applications articles sharing the title, “Vitamins for Chronic Disease Prevention in Adults“. The objective of the Scientific Review is to review the clinically important vitamins’ effects, sources, deficiency syndromes, toxicity, and relationship to chronic disease. The review of studies published from 1966 through 2001 on nine nutrients revealed a population consisting of the elderly, alcohol-dependent individuals, vegans, and those with malabsorption who are at risk of inadequate intake or absorption of several of these nutrients. The Clinical Applications article notes that although deficiency diseases such as scurvy and pellagra are rare, insufficient vitamin intake is a cause of chronic diseases, and that suboptimal levels of vitamins, even though these levels might be well above those classified as deficient, are risk factors for osteoporosis, cardiovascular disease and cancer.
The authors examined studies concerning the following nutrients: vitamins A, B6, B12, C, D, E and K, folate, and the carotenoids including alpha and beta-carotene, beta-cryptoxanthin, lycopene, lutein and zeaxanthin. They noted the association of low intakes of the B vitamins with elevated homocysteine levels and the corresponding increased risk of coronary heart disease disease; of low folate with neural tube defect, coronary heart disease and breast and colorectal cancer; of vitamin B6 deficiency with cheilosis, stomatitis, central nervous system effects and neuropathy; of low B12 with macrocytic anemia and neurologic abnormalities; of suboptimal vitamin E with prostate cancer; of low levels of various carotenoids with breast, prostate and lung cancer; of vitamin D with secondary hyperparathyroidism, bone loss, osteoporosis and increased fracture risk; of vitamin C with cancer in some studies, of vitamin A with vision disorders and decreased immune function, and of vitamin K with blood clotting disorders and possibly with increased fracture risk.
In the “Clinical Applications” article, Drs Fletcher and Fairfield conclude that a large proportion of the general population is at increased risk of cardiovascular disease, cancer, osteoporosis and other chronic diseases because of suboptimal vitamin levels. The high prevalence of these diseases indicates the standard diet in the U.S. fails to provide sufficient amounts of the vitamins studied. They write, “Pending strong evidence of effectiveness from randomized trials, it appears prudent for all adults to take vitamin supplements.” This is a significant move forward from the notion that all of one’s nutritional needs can be met by diet alone that the medical establishment has been advising for decades.