Vitamin C reduced risk for heart disease and increased fertility in men in two new studies. In the heart disease study, reported in the American Journal of Clinical Nutrition, doctors in Britain recruited 3,258 men, aged 60 to 79, who had not been diagnosed with heart attack (myocardial infarction), stroke, or diabetes. Researchers measured the levels of fruits, vegetables, and vitamin C in the diet through a food questionnaire. To determine heart disease risk, doctors measured blood levels of a type of protein (C-reactive protein, or CRP) that signals acute inflammation; and a type of enzyme (tissue plasminogen activator, or t-PA), which indicates that blood vessels may be stiffening.

Compared to men with the lowest blood fluid (plasma) levels of vitamin C, men with the highest plasma levels of vitamin C were 44% less likely to have elevated CRP levels, and 21% less likely to have elevated t-PA. Compared to men who ate the fewest fruits, men who ate the most fruit were 24% less likely to have elevated CRP or t-PA. Men who ate the most vegetables were less likely to have elevated t-PA levels compared to men who ate the fewest vegetables. The doctors noted that blood was less likely to abnormally thicken and clot in men with the most plasma vitamin C.

In the fertility study, researchers recruited 13 otherwise healthy but infertile men, aged 25 to 35, who took 1,000 mg of vitamin C twice per day. After two months, average sperm count had increased 129%, independent and spontaneous movement (sperm motility) increased 93%, and normal shape (sperm morphology) rose 55%. Doctors concluded that vitamin C supplements may improve the quality of semen and odds of conception.

Reference: Journal of Medicinal Food; 2006, Vol. 9, No. 3, 440-2.