Boston, MA–The largest, prospective study to date, by Brigham and Women’s Hospital and Harvard School of Public Health researchers, suggests that women with the highest intake of folate and vitamin B6 cut their heart disease risk in half when compared to women with the lowest intake. The authors examined the question of folate and B6 impact on coronary heart disease (CHD) since low intake of both vitamins has been linked to elevated blood homocysteine levels (hyperhomocysteinemia), a cause of arterial occlusion. The results are reported in this week’s Journal of the American Medical Association and come from the Nurses’ Health Study.
In the study group, the largest contributor to overall intake of folate and B6 are multiple vitamins and fortified cold cereals. The other foods which contribute most to folate intake are orange juice, green leafy vegetables, broccoli and eggs. The foods contributing to intake of vitamin B6 are bananas, chicken, beef, potatoes, fish and whole grains. Comments Eric Rimm, ScD, assistant professor of epidemiology and nutrition at the Harvard School of Public Health, and lead author of the study, “Because intake of multiple vitamins is so prevalent in this population, we can measure the independent effects of these vitamins from the diet or from supplements. From either source, we found an inverse association with heart disease risk.”
He adds, “We were surprised to see that for women with the highest intake of both vitamins in the diet, heart disease risk was almost cut in half, compared to women with low intake of both. In fact, our findings suggest that to reduce risk of coronary heart disease, daily vitamin intake of folate and B6 ought to be higher than the current RDA. Women with the lowest risk of heart disease had average intakes of at least 500 ìg/d for folate and 3 ìg/d for vitamin B6.”
An intriguing finding, say the authors, that needs further confirmation pertains to women who drink moderately and have a high folate intake. Previous studies have shown a relationship between moderate drinking (1-2 drinks per day) and reduction in heart disease risk. The women at the lowest risk of all for CHD, those who drink and have a high folate intake, have a dramatically reduced risk (80%) of CHD when compared to women with low vitamin intake and who do not drink.
The Nurses’ Health Study is an on-going prospective study of women, age 30-55 at enrollment in 1976. The study is directed by Frank Speizer, MD, Brigham and Women’s Hospital and Harvard Medical School. Subjects were subsequently followed every two years and asked to answer questionnaires concerning their diet, lifestyle and health.
Harvard School of Public Health is dedicated to advancing the public’s health through learning, discovery, and communication. More than 300 faculty members are engaged in teaching and training the 900-plus student body in a broad spectrum of disciplines crucial to the health and well being of individuals and populations around the world. Programs and projects range from the molecular biology of AIDS vaccines to the epidemiology of cancer; from risk analysis to violence prevention; from maternal and children’s health to quality of care measurement; from health care management to international health and human rights.
Source: Harvard School of Publich Health news release, 1998.