Vitamin intake is not associated with community-acquired pneumonia in U.S. men

The age-related decline in immune function may predispose individuals to increased infection risk. Nutrition is an important determinant of immunocompetence, but vitamin supplementation in relation to infection has not been evaluated extensively in well-nourished populations. We evaluated the associations between intakes of antioxidants and B vitamins and risk of community-acquired pneumonia in well-nourished, middle-aged and older men. This was a prospective study conducted between 1990 and 2000 among 38,378 male, U.S. health professionals, aged 44 to 79 y in 1990. Participants answered a detailed 131-item FFQ to assess diet and also provided information on vitamin supplement use. We included those who at the onset had no history of pneumonia, myocardial infarction, stroke, other heart disease, arterial surgery, cancer or asthma, and also had complete dietary data. There were 446 new cases of nonfatal community-acquired pneumonia during 145,878 person-years of follow-up. After adjustment for age, smoking, BMI, alcohol use, physical activity, diabetes and total energy intake, there were no associations between total intakes of antioxidants or B vitamins and pneumonia risk. After excluding men who took vitamin E supplements, vitamin E intake from food sources only was inversely associated with pneumonia risk (multivariate relative risk comparing extreme quintiles = 0.58, 95% CI, 0.39-0.86, P-value test for trend = 0.01). Vitamin supplements are unlikely to reduce pneumonia risk in well-nourished, middle-aged and older men.