Antioxidant Vitamins Protect Men Against COPD

Men who take the antioxidant vitamins C and E are at reduced risk for chronic obstructive pulmonary disease (COPD), according to a new prospective study.

Some studies have suggested that dietary antioxidants may have a protective role against COPD. This prospective study found that antioxidant vitamins, particularly vitamins C and E, have a beneficial effect on the risk of COPD and lung function, according to spirometry measurements of forced expiratory volume (FEV₁) and forced vital capacity (FVC).

“In addition, the antioxidant effects of vitamins C and E on the risk of COPD might be stronger in men who smoke than in noncurrent smokers,” stated the researchers, led by Pankaj Joshi, BPH, MS, PhD, of the Department of Preventive Medicine at Kangwon National University School of Medicine in South Korea.

The researchers evaluated 10,038 patients from the community-based Korean Genome Epidemiology Study cohort. From these patients, they identified 325 patients with COPD and 6781 patients who were at risk.

The risk of COPD was positively associated with aging, low education, low household income, lower body mass index, and cigarette smoking.

“The risk of COPD decreased with increase in the dietary vitamin C and vitamin E intake, predominantly in men,” the researchers stated. “In addition, the lung function was significantly improved with increase in vitamins C and E intake.”

No statistically significant interactions were observed between smoking and vitamin C or E intake in relation to COPD risk among men.

The researchers noted that the protective effect of vitamins C and E on lung function was dose-dependent. “An increase in vitamins C and E intake was significantly associated with an increase in FEV₁ and FVC. For the combined effect of smoking and the selected antioxidant vitamins on COPD risk among men, we observed that the current smoker with the lowest vitamin C or E intake had a higher relative risk than the noncurrent smoker with the highest intake of the vitamins C or E,” they stated, although this interaction was not statistically significant.

The researchers found that an increase in vitamin C intake of 100 mg/d was significantly associated with increase in FEV₁ and FVC, consistent with the findings of several studies.

Also consistent with other studies, they observed an increased risk of COPD in older patients, men, and those with a history of tuberculosis or asthma.

In conclusion, the researchers stated, “Our results suggest the independent beneficial effect of antioxidants, particularly vitamins C and E, on COPD risk and lung function in men.”