Deficiency of vitamin D and vitamin C in the pathogenesis of bronchial asthma.

Epidemiology of bronchial asthma (BA) indicates a marked paradox: rapid rise in the prevalence.Simultaneous decline in mortality is mostly related to improvement in the diagnosis and therapy. In many economically developed countries the BA affects more than 10 per cent of the population, while mortality related to this respiratory disorder is below 1/100,000. Factors favorably influencing mortality of BA include new more effective medications, decline in smoking and also improved nutrition, based on awareness of protective role of vitamins. Vitamin D deficiency has a number of biological effects that are potentially instrumental in the pathogenesis and severity of BA. Increased number of randomized, controlled, interventional studies is showing positive effects of vitamin D supplementation in pediatric and in adult BA. Oxidative stress is potentially an important pathogenic factor in the progression of BA. Vitamin C (ascorbic acid) belongs to the most effective nutritional antioxidants. By counteracting oxidants, reducing generation of reactive oxygen species, vitamin C may inhibit external attacks in the respiratory tract, thus modulating the development of BA (Fig. 2, Ref. 15).