We challenge the question of how environmental (diet, physical activity, alcohol) factors modify genetic associations put forward by us and others, in recent genome wide association studies (GWAS) of lipoprotein traits, cardiovascular disease (CVD) and obesity and aim to utilize this information in intervention studies and in development of prediction models. We work to further improve genetic CVD / obesity risk prediction by extending our previous genetic risk scores with the exploding knowledge on CVD and obesity genetics currently evolving. Importantly, by combining expertise in multifactorial genetics/ genetic epidemiology / molecular biology with nutrition epidemiology and systems biology, we take steps further challenging the question of interactions between the genetic and environmental risk factors of these traits in very large epidemiological cohorts with long follow-up times and world-unique dietary data available (Malmö Diet and Cancer Study).