विटामिन और खनिज

Our bodies are normally well protected against continual attack from pathogens and noxious insult by a complex and integrated immune system. However, daily bombardment from indoor and outdoor air pollutants can compromise immune function and ultimately lead to infection (e.g. acute respiratory tract infections, diarrhoea) and conditions such as sick building syndrome (with mucosal, skin and general symptoms). All of us may be affected by reduced air quality, although certain factors increase the risk of impaired immunity (e.g. young or advancing age, exposure to tobacco smoke, close proximity to areas of high air pollution, office work, commuting). A major exogenous factor modulating immune function is nutrition; even subclinical deficiencies in various nutrients can have adverse effects on the immune system, which may be exacerbated by environmental threats. In particular, the oxidant-antioxidant balance (vital for communication within the immune system) may be affected. Dietary supplementation can help to restore immune function to the normal range, and an antioxidant-containing multivitamin supplement has been shown to ameliorate the symptoms of sick building syndrome, acute respiratory tract infections and diarrhoea. This review looks at the impact of reduced air quality on the oxidant-antioxidant balance and the role of selected micronutrients (vitamins A, D, E, C, B6, B12, folate and the trace elements copper, iron, selenium and zinc) and multivitamin supplementation.