Dietary nutrients and blood pressure in urban minority adolescents at risk for hypertension

Objective: To determine if blood pressure (BP) level is associated with dietary micronutrients in adolescents at risk for hypertension. Design: Adolescents aged 14 to 16 years, with BP higher than the 90th percentile on 2 separate measurements in a school setting, had diet assessments. A 24-hour intake recall was obtained on 180 students (108 boys and 72 girls). Folic acid intake was used as an index of fruit, vegetable, and whole grain intake; the high folate group had a folate intake greater than the recommended daily allowance and the low folate group had a folate intake less than the recommended daily allowance. Data were analyzed by 2-way analysis of variance. Results: Mean diastolic BP was significantly higher in the low folate vs the high folate group (boys: 72 vs 67 mm Hg; girls: 76 vs 73 mm Hg; P=.008). The difference in systolic blood pressure was not significant. There was no difference in body mass index between the diet groups. Sodium intake per 4184 kJ was not different. The low folate group had significantly lower intakes per 4184 kJ of potassium (P=.002), calcium (P=.001), magnesium (P<.001), and total intake of beta carotene, cholecalciferol, vitamin E, and all B vitamins. Conclusions: Among adolescents at risk for hypertension, BP was lower in those with higher intakes of a combination of nutrients, including potassium, calcium, magnesium, and vitamins. Dietary benefits on BP observed on diets rich in a combination of nutrients derived from fruits, vegetables, and low-fat dairy products could contribute to primary prevention of hypertension when instituted at an early age.