An inverse relationship between serum vitamin C and blood pressure in a Japanese community

To examine the relationship between serum vitamin C concentration and blood pressure level, a cross-sectional study was conducted. The subjects were 9 19 men and 1,266 women aged 40 years and over in a Japanese provincial city , Shibata, Niigata Prefecture. The mean and standard deviation of systolic blood pressure (SBP) were 134.0 +/- 20.0 mmHg for men and 128.3 +/- 20.8 mm Hg for women, and those of diastolic blood pressure (DBP) were 81.0 +/- 11. 7 mmHg and 75.8 +/- 11.4 mmHg, respectively. The mean and standard deviatio n of serum vitamin C were 42.5 +/- 18.6 mu mol/L for men and 56.8 +/- 16.5 mu mol/L for women. SEP and DBP were both inversely correlated with serum v itamin C concentration. The means of SEP or DBP were calculated for quartil es of serum vitamin C, and the significant inverse relationship was observe d in any sex and age group. The inverse association persisted after adjustm ent for possible confounders: body mass index, serum total cholesterol, alc ohol consumption, smoking, physical activity, antihypertensive medication, and dietary intake of salt, calcium, and potassium. Serum vitamin C appeare d to be inversely related with both SEP and DBP in this Japanese population , although further intervention and experimental studies were required to e stablish the cause-effect relationship.