Does vitamin deficiency cause asthma?

Children with asthma were found to have significantly decreased serum levels of vitamin E, beta-carotene, and vitamin C even when they had no symptoms, and higher levels of lipid peroxidation products during attacks. Using antioxidant nutrients might be helpful in combating the increased oxidant levels in asthmatics.

Epidemiological studies on respiratory function note a beneficial overall effect on respiratory function from taking vitamin C. Yet the effect of vitamin C on asthma remains controversial, because studies have yielded contradictory results.