Background: Prospective data on the relation between whole grain intake and incident hypertension in men are limited, and no previous studies have quantitatively estimated total grams of whole grains in relation to risk of hypertension.
Objective: The purpose of this study was to estimate the association of whole-grain intake (g/d) and risk of incident hypertension in a large prospective cohort of men.
Design: The Health Professionals Follow-Up Study is a prospective cohort consisting of 51,529 male health professionals ranging in age from 40 to 75 years at enrollment in 1986. Baseline and updated measurement of whole-grain intake as well as important covariates were measured, and 31,684 participants without known hypertension, cancer, stroke, or coronary heart disease were followed prospectively for 18 years through 2004 for onset of hypertension.
Results: A total of 9,227 cases of incident hypertension were reported over the 18 years of follow-up.
In multivariate-adjusted analyses, whole-grain intake was inversely associated with risk of hypertension [more whole grain, less risk of high blood pressure], with a relative risk (RR) of 0.81 (95% CI: 0.75-0.87) in the highest compared with the lowest quintile (P for trend < 0.0001). [Note: a relative risk of 1.0 would indicated no difference in risk between the highest and lowest grain intake groups. An RR of 0.81 represents a 19% difference in risk.]
In the multivariate model, total bran was inversely associated with hypertension, with a relative risk (RR) of 0.85 (95% CI: 0.78, 0.92) in the highest compared with the lowest quintile (P for trend: 0.002).
Conclusions: In summary, we found an independent inverse association between intake of whole grains and incident hypertension in men. Bran may play an important role in this association. These findings have implications for future dietary guidelines and prevention of hypertension.
Source: American Journal of Clinical Nutrition, Sep 2009;90(3):493-8. PMID: 19571218, by Flint AJ, Rimm EB, et al, (Address: Departments of Epidemiology and the Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA). [E-mail: email@example.com]