During the evaluation of the diet, the subjects have to continue with the same degree of physical activity as previously. No dietary supplements such as fish oil, probiotics or multivitamin drugs are allowed to take. As most one visit to a restaurant or to another diet per week is allowed. Journeys or a stay during a longer time period at another place must be discussed with the leader of the research. Maximal intake of alcoholic beverages is 30 g ethanol/week. 12 g ethanol corresponds to the following: 1 bottle (50cl) ordinary beer, 1 bottle (33cl) strong beer, 1 glass (15cl) wine, 1 glass (8cl) strong wine, or 1 glass (4cl) spirits. formula: volume% x ml volume/100 x 0.8.