Asthma is one of the most widespread chronic diseases in childhood worldwide. In Germany about 10 percent of all children suffer from asthma. In international studies the reasons for this respiratory disease are assumed and investigated in many different fields, such as genetic predisposition, exposition to allergens and endotoxins or social status and further factors. It is the aim of this paper to discuss if weight at an early age – measured against the BMI – may have an influence on the development of a respiratory disease and asthma bronchiale. In order to clarity this issue an essay on the possible effects of indoor factors on children´s trouble in breathing was consulted. The investigation was carried out on 801 children in the District of Heinsberg (Germany), Middel Limburg (the Netherlands) and Westlijke Mijnstreek (the Netherlands) in 1997; 333 children of them had troubles in breathing, 468 children did not have any symptoms. Beside the factor overweight, the influence of other factors such as gender, premature birth, birth weight, smoking during pregnancy, breastfeeding, social origin and status, passive exposition to smoke and the family case history were considered in the calculations. Risk factors for the development of a respiratory disease and particularly asthma are: male sex, smoking throughout pregnancy as well as passive exposition to smoke, having a low or middle social status as well as a positive asthma case history of the mother or siblings. Weight is also a proven risk factor: with growing BMI the risk of respiratory trouble also grows. Within this context Cole´s cutpoints did not turn out to be significant, especially not for the prevalence of respiratory diseases such as asthma. On the other hand, factors such as origin, birth weight, premature birth, breastfeeding as well as the father´s positive asthma case history do not have any influence on the development of asthma. The relevant literature on this subject on the one hand comes to clearly different results, but on the other also ...