With the presentation of the blueprint of the first human genome in 2001 and the advent of technologies for high‐throughput genetic analysis, personalized nutrition (PN) becomes a new scientific field and the first commercial offerings of genotype‐based nutrition advice emerge at the same time. Here, the state of evidence for the effect of genetic and epigenetic factors in the development of obesity, the metabolic syndrome, and resulting illnesses such as non‐insulin‐dependent diabetes mellitus and cardiovascular diseases is summarized. This study also critically value the concepts of PN that are built around the new genetic avenue from both the academic and a commercial perspective and their effectiveness in causing sustained changes in diet, lifestyle, and for improving health. Despite almost 20 years of research and commercial direct‐to‐consumer offerings, evidence for the success of gene‐based dietary recommendations is still generally lacking. This calls for new concepts of future PN solutions that incorporate more phenotypic measures and provide a panel of instruments (e.g., self‐ and bio‐monitoring tools, feedback systems, algorithms based on artificial intelligence) that increases compliance based on the individual´s physical and social environment and value system. Personalized nutrition is of great interest in research, but also in the public. Most concepts of personalized nutrition consider genetic information. To date, personalized nutrition concepts lack scientific evidence, but are offered in many ways by commercial providers.