Higher serum antioxidant vitamins predict lower risk of respiratory illness and mortality
July 1 2022. A pooled analysis published on June 9, 2022, in Respiratory Research concluded that having lower serum levels of vitamins C and E was associated a greater risk of suffering from wheeze or respiratory diseases, and that lower vitamin A, C and D were associated with an increased risk of dying from respiratory diseases.
Paivi M. Salo and colleagues analyzed data from 16,218 men and women who participated in the National Health and Nutrition Examination Survey III (NHANES III), conducted from 1988 to 1994, and 17,838 adults who were continuous NHANES participants during 1999 to 2006 who had information available concerning at least one serum antioxidant vitamin level. Questionnaires completed upon enrollment provided data concerning the presence of wheezing during the previous year, and chronic lower respiratory disease diagnoses, including asthma, bronchitis or emphysema. Deaths from chronic lower respiratory disease, influenza or pneumonia were ascertained through 2015. Forty-two percent of the participants reported using vitamin supplements.
Lower vitamin C levels were associated with a greater risk of wheeze. Among smokers, lower levels of the alpha-tocopherol form of vitamin E were associated with increased wheeze and chronic bronchitis/emphysema.
A higher risk of death from chronic lower respiratory disease was associated with lower levels of vitamin C. Among smokers with lower levels of 25-hydroxyvitamin D, chronic lower respiratory disease and influenza/pneumonia deaths were increased. Greater influenza and pneumonia mortality was also associated with lower vitamin A levels. In pooled analysis of NHANES III and continuous NHANEs participants, vitamin C deficiency doubled the risk of dying from influenza or pneumonia in comparison with sufficiency.
“Ours is the largest and most comprehensive epidemiological study on serum antioxidant vitamins and respiratory morbidity and mortality in adults conducted to date,” the authors announced. “The results underscore the importance of antioxidant vitamins in respiratory health.”