In the early years of the KOALA-study we focussed on nutritional factors and microbial exposures that could protect against the development of allergy and asthma. Examples of nutritional factors of interest are breast and formula feeding, essential fatty acids, vitamin D, folate. Examples of microbial factors are: gastrointestinal viral infections, gut microbiota (intestinal microflora), helminth infections, vaccinations, pro-, pre- and antibiotics. Gene-diet and gene-environment interactions are the focus of the genetic studies, which are manly performed in collaboration with other birth cohorts. As the children grow older, the focus is broadened to asthma, lung function, physical fitness and physical activity, seeking the synergy with the second theme.
The biomedical relations of our interest are perinatal and childhood influences on development of overweight and obesity, and metabolic, inflammatory and cardiovascular risk factors for adult adverse health outcomes. Measurements include, physical activity (accelerometry), fat distribution, blood pressure and physical fitness. Psychosocial research is directed at the role of parenting practices and habit formation on the development of overweight and obesity in childhood. This is not only studied in the family, but also in other environments where children grow up: day-care centre, school and neighbourhood.