Previous population studies have suggested that the increasing frequency of asthma in Western societies may be associated with changes in diet that have led to decreased intakes of antioxidants such as vitamin C. This study investigated the possibility that decreased levels of antioxidants may also contribute to severe asthma, which imposes a considerable social and economic burden on the community.
Neil Misso (Asthma & Allergy Research Institute, Nedlands, Australia) and his colleagues compared the dietary intakes and blood concentrations of antioxidants, including vitamin C, in 28 patients with severe asthma compared with 53 mild asthmatic patients and 43 subjects without asthma. Among all subjects the dietary intakes of vitamin C and carotene, which are mainly derived from fruit and vegetables, were lower in males than in females, and males with severe asthma had a particularly low intake of these antioxidants.
The blood concentrations of vitamin C were markedly lower in patients with severe asthma compared to subjects with mild asthma or those without asthma, and this difference was observed in both males and females. An unexpected but interesting observation was that patients with severe asthma were more overweight, had a higher intake of fat and a higher blood cholesterol concentration compared with the other subjects. In addition, lung function was better in subjects with high blood vitamin C and low blood cholesterol concentrations.
These results suggest that patients, and particularly males, with severe asthma may benefit from modification of their diet to ensure an adequate intake of antioxidants such as vitamin C.
Further studies are required to confirm whether this strategy, which would be relatively easy to implement, may help in decreasing the morbidity and socioeconomic burden associated with severe asthma.
The European Respiratory Journal is the peer-reviewed scientific publication of the European Respiratory Society (more than 7,000 specialists in lung diseases and respiratory medicine in Europe, the United States and Australia).
European Respiratory Journal
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