The obesity epidemic could be fuelling Britain’s growing problem of loneliness, scientists believe, after discovering a genetic link between the two conditions.

Around a quarter of people over 65 in Britain suffer from loneliness, which can raise the risk of many diseases, and can even cause people to die earlier, while nearly two thirds are overweight.

Researchers at the University of Cambridge discovered that similar areas in genes which increase the likelihood of people being overweight also influence social isolation.

It is the first study to show a causal link between loneliness and obesity, and scientists suggest that it is possible to tackle the loneliness epidemic by encouraging people to lose weight.

Dr John Perry, senior scientist at Cambridge University, said: “This study has enabled us to use genetics to identify a causal association between loneliness and obesity.

“We often think that loneliness is driven purely by our surrounding environment and life experiences, but this study demonstrates that genes can also play a role.

“There is always a complex mix of genes and environment, but it does suggest that at a population level, if we could tackle obesity we would be able to bring down loneliness as well.”