Effect of vitamin C on ambulatory blood pressure and plasma lipids in older persons

J Hypertens. 2000 Apr;18(4):411-5. doi: 10.1097/00004872-200018040-00009.


Objectives: To determine the effect of oral vitamin C supplements on ambulatory blood pressure and plasma lipids.

Design: A 6-month double-blind randomized placebo-controlled cross-over study with a 1 -week washout between cross-over periods.

Methods: Vitamin C 500 mg daily or matching placebo was given to 40 men and women aged between 60 and 80 years for 3 months each in a cross-over fashion. Clinic and 24-h ambulatory blood pressure, plasma ascorbate and lipids were measured at baseline and at the end of each cross-over phase.

Results: Clinic blood pressure did not change between placebo and vitamin C phases. Daytime ambulatory blood pressure showed a small but significant fall in systolic blood pressure (2.0 +/- 5.2 mmHg; 95% confidence interval 0-3.9 mmHg) but not in diastolic blood pressure. Regression analysis showed that with increasing baseline daytime blood pressure the fall in blood pressure with vitamin C supplementation increased. Regression analysis of the change in high-density lipoprotein (HDL) cholesterol showed a significant effect of sex on the change in HDL cholesterol. In women, but not men, HDL cholesterol increased significantly by 0.08 +/- 0.11 mmol/l, P=0.007. There was no change in low-density lipoprotein cholesterol between treatment periods.

Conclusion: In older adults high intakes of ascorbic acid have modest effects on lowering high systolic blood pressure, which could contribute to the reported association between higher vitamin C intake and lower risk of cardiovascular disease and stroke.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aging / blood
  • Aging / physiology*
  • Ascorbic Acid / blood
  • Ascorbic Acid / pharmacology*
  • Blood Pressure / drug effects*
  • Blood Pressure Monitoring, Ambulatory
  • Cross-Over Studies
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Female
  • Humans
  • Hypertension / physiopathology
  • Lipids / blood*
  • Male
  • Reference Values
  • Systole


  • Lipids
  • Ascorbic Acid