This is surprising given the scale of the problem. In the UK more than 1 in 2 adults in the UK are overweight and almost 1 in 5 are clinically obese. People who are obese are almost twice as likely to die prematurely than their lean counterparts and they suffer a greatly increased risk of a range of serious diseases, including diabetes, heart disease and cancer. This places a growing strain on healthcare budgets and is the cause of huge personal suffering. The time is long overdue to treat obesity seriously.
Obesity is a complex trait where many social, behavioural and biological factors are involved.
For example, it is well known that a facilitating environment, such as abundant food supply and poor physical activity, will favour the accumulation of fat. But, it is also well known that different individuals, experiencing the same environment, will not have the same propensity to store fat. It is here, therefore, that the different forms of the genes carried by individuals could make a difference. For most of the cases, it is suspected that a combination of multiple genes, together with a permissive multifactorial environment, will cause obesity. Over the past six years, we have tried to make an overview of all the candidate genes and loci for obesity that have been studied in different populations for fat-related phenotypes.