Nutrition Update

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JAMA article recommends vitamin supplements for all adults.

The June 19 2002 issue of the Journal of the American Medical Association

(http://jama.ama-assn.org/) 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.