More than 1,000 obese people are screened for genetic mutations (MC4R). Those with positive screenings as well as 320 randomly selected people without MC4R mutations are randomized to 2 consultation types: one including recommendations for eating and physical activity behavior, the other with an additional part on genetic determinants and actions in obesity. Their results are compared to a control group (n>100). It is hypothesized that obese people with obesity-specific genetic mutations, and obese people with a family history of obesity, benefit more if the consultation includes additional elements on genetic determinants.