Genes influence every aspect of human physiology, development, and adaptation. Obesity is no exception.
But genetic factors identified so far make only a small contribution to obesity risk: many people who carry these so-called “obesity genes” do not become overweight, and healthy lifestyles can counteract these genetic effects.
Nutrition also plays a role in the duration and quality of life.
Epigenetics is a rapidly evolving area of research and the first steps are already being made in identifying potential biomarkers for obesity that could be detected at birth.
There is compelling evidence that an adverse prenatal and early postnatal environment can increase obesity risk in later life. Diet and weight loss interventions in obese mothers may lead to a decreased risk of obesity in the offspring, possibly mediated through changes in insulin signalling, fat storage, energy expenditure or appetite control pathways.
These findings may help in predicting an individual’s obesity risk at a young age, before the phenotype develops, and opens possibilities for introducing targeted strategies to prevent the condition.
It is also now clear that several epigenetic marks are modifiable, not only by changing the exposure in utero, but also by lifestyle changes in adult life, which implies that there is the potential for interventions to be introduced in postnatal life to modify or rescue unfavourable epigenomic profiles.