High-dose short-term folate administration modifies ambulatory blood pressure in postmenopausal women. A placebo-controlled study.

In humans low intake or low levels of folate are related to elevated homocysteine (Hcy) or blood pressure (BP). This study was performed to test whether in healthy postmenopausal women a 3-week administration of folate (5-methyltetrahydrofolate: 5-MTHF) at the dose of 15 mg/day (n=15), was, in comparison to placebo (n=15), capable of modifying 24-h ambulatory BP, along with Hcy and insulin metabolism. Placebo did not modify any parameter. 5-MTHF significantly decreased nocturnal systolic (-4.48+/-1.8 mm Hg; P=0.029), diastolic (-5.33+/-1.3 mm Hg; P=0.001) and mean (-5.10+/-1.1 mm Hg; P=0.005) BP, in a way that was significantly different from that observed during placebo. 5-MTHF also reduced Hcy (11.77+/-1.15 vs 8.71+/-0.50 micromol/l; P=0.03), and insulin resistance, evaluated by HOMA-IR (2.58+/-0.04 vs 2.03+/-0.04; P=0.01). Whether maintained in the long term, 5-MTHF's cardiovascular and metabolic effect may contribute to primary cardiovascular prevention of postmenopausal women.