IHN Database

Vitamin C and longevity

LONDON, UNITED KINGDOM. Researchers at the London School of Hygiene and Tropical Medicine report that older people with high blood levels of vitamin C live longer than people with low levels. Their study involved 1214 people between the ages of 75 and 84 years. All participants had a blood sample drawn for analysis of vitamin C (ascorbate), vitamin E, vitamin A (retinol), and beta-carotene levels. They also completed detailed food frequency questionnaires during a personal interview.

The researchers found that ascorbate concentrations decreased markedly with age and that participants with the highest blood levels of ascorbate (greater than 66 micromol/L) had about half the risk of dying during the 4-year follow-up period as did participants with the lowest blood levels (less than 17 micromol/L). Blood levels of the other antioxidants measured did not correlate with mortality.

Ascorbate levels correlated well with fruit and vegetable intake of at least 5 servings per day. Only 17% of the participants took vitamin C supplements and doing so did not affect the correlation between blood levels of ascorbate and mortality. Men, smokers, sedentary people, and people of a lower socioeconomic status were more likely to be vitamin C deficient. The researchers conclude that an effort should be made to increase ascorbate levels in older people preferably through an increased intake of fresh fruit and vegetables.
Fletcher, Astrid E., et al. Antioxidant vitamins and mortality in older persons. American Journal of Clinical Nutrition, Vol. 78, November 2003, pp. 999-1010

Editor's comment: Other research has shown that supplementing with 400 mg/day of vitamin C yields an equilibrium ascorbate level of about 70 micromol/L in healthy young volunteers. It is likely that older people may require more, so 300-500 mg 3 times a day is probably a good aim. Vitamin C should always be taken in divided doses throughout the day as it is fairly rapidly excreted. It is also prudent to supplement with a combination of vitamin C and the bioflavonoids usually found with it in nature rather than with just pure ascorbic acid.

category search
Keyword Search

copyright notice