Positive Health Online

Abstract

HARIK-KHAN and co-workers, Clinical Research Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA, write about the levels of antioxidant vitamins in serum and the risk of asthma in children.

Background

The dietary intake of the antioxidant vitamins A, C, E, and of carotenoids has been linked to the presence and severity of asthma. This study examined some of the data collected in the Third National Health and Nutrition Examination Survey, conducted in the US between 1988 and 1994, for evidence that low antioxidant vitamins are associated with asthma.

Methodology

4,093 children between the ages of 6 and 17 were selected and their data analyzed.

Results

9.7% of these children reported a diagnosis of asthma. Bivariate analysis showed that asthma diagnosis was associated with lower levels of serum vitamin C, alpha-carotene, beta-carotene, and beta-cryptoxanthin (another carotenoid). In order to take into account the fact that antioxidant levels may be surrogate markers for socioeconomic variables such as race, poverty, tobacco exposure, or malnutrition, logistic models that included these variables were utilized. After these corrections, the only antioxidants significantly associated with asthma were vitamin C and alpha-carotene, with a more pronounced association of vitamin C (odds ratio between the highest and lowest quintile of serum vitamin C was 0.65).

Conclusion

Low vitamin C and alpha-carotene intakes are a risk factor for asthma in children.

References

Harik-Khan RI, Muller DC, Wise RA. Serum vitamin levels and the risk of asthma in children. American Journal of Epidemiology 159 (4): 351-357, Feb 15, 2004.