Hardening of the arteries, known as atherosclerosis, is a common heart condition, often associated with type 2 diabetes. In a study at the Royal Victoria Hospital in Ireland, researchers found that vitamin C can help reduce blood pressure and arterial stiffness in adults with type 2 diabetes.

In this double-blind study, 30 patients, aged 45 to 70 years, all with type 2 diabetes, were given either a placebo or 500 mg of vitamin C (ascorbic acid) daily. Testing for arterial and aortic stiffness was done at the beginning and end of this four-week study.

Upon completion, tests showed that those taking vitamin C did in fact decrease their blood pressure. According to the researchers, supplementation with vitamin C may be a useful adjunct to conventional treatment to slow arterial stiffness. Vitamin C is an antioxidant vitamin.

Another recent study also looked at the role of antioxidants against atherosclerosis —specifically, vitamins C and E. In this six-year comprehensive study, the subjects were 520 smoking and nonsmoking men and postmenopausal women, all aged 45 to 69 years. All subjects were given a combination of 136 IU of vitamin E and 250 mg of vitamin C daily throughout the trial.

The overall results showed atherosclerotic progression was slowed by an average of 26% — 33% for men and 14% for women. Participants who were low in vitamin C to begin with showed the most improvement. While they did not provide a theory for why the men were more affected than the women, they did conclude that vitamins C and E did help slow atherosclerosis, a major contributor to heart disease.

Sources: Hypertension 2002 Dec;40(6):804-809; Circulation 2003 Feb 25;107(7):947-53