Folate Associated with Decreased Risk of Hypertension

Category: Conditions of the Circulatory System , Dietary Supplements

A study published in the Journal of the American Medical Association (January 19, 2005293(3):320-329) examined the relationship between folate intake and one's risk for developing hypertension.

This research was part of larger well known program known as the Nurses Health Study which has provided an abundance of data on dietary health to date. This prospective research was conducted based on knowledge of the effect of folate on endothelial cell function. Previous studies showing that folate supplementation can reduce both systolic and diastolic blood pressure.

Two large cohorts of women were previously established, one of 93803 women aged 25-42, the other of 62260 women aged 30-55. These women completed comprehensive dietary questionnaires every 4 years and from that information, folate intake was rather accurately calculated. As well, if a diagnosis of hypertension had been made over the previous 2 years, it was also indicated in the biennial medical questionnaire. In many cases, medical record review was used to confirm the diagnosis. The data for this experiment was analyzed over an 8 year period beginning in 1991.

The results showed that in the younger cohort, folate intake was indeed associated with a lower risk of hypertension. Consumption of 1000ug/d or more of total folate (dietary and supplementation) had a 46% and 40% reduction in the risk of incident hypertension after adjusting for multiple confounders versus women who only consumed less than 200ug/d and 400ug/d respectively. The results were similar, but not as great, in the older cohort of women. Further analysis revealed that the supplemental folate was responsible for the significant reduction in risk of hypertension, while dietary folate alone had no statistically relevant effect.

The authors conclude that "Higher total folate intake was significantly associated with a reduced risk of incident hypertension even after controlling for a large number of covariates including dietary intake, physical activity, BMI, and family history." Interestingly, the results showed a greater association in the younger cohort of women. The authors explain the effect of supplemental folate may be due either to bioavailability or being able to attain higher levels of folate. This is the first prospective study to report an association between folate intake and the risk of incident hypertension.

The significant outcome of the 2005 research study can possibly impact public health recommendations. The conclusion the researchers made was that higher intakes of folate decrease the risk of hypertension, especially in young women.

Posted by Kristopher Foster on December 24, 2008 10:00 AM