Loneliness is a killer: It's as bad for your health as alcoholism, smoking and over-eating, say scientists

Obesity and alcoholism may be bad for your health, but there’s a less obvious condition out there that is just as dangerous – loneliness.

According to a study the support of family, friends and neighbours can increase your chances of living to a healthy old age by 50 per cent. But the findings, based on an analysis of more than 300,000 people, suggest social isolation is as bad for your health as smoking 15 cigarettes a day or being an alcoholic. It also does more damage to your health than not exercising – and is twice as harmful as obesity.

The American scientists who made the discovery say lack of social support should be added to the ‘short list’ of risk factors for an early grave. Dr Julianne Holt-Lunstad, of Brigham Young University in Utah, who led the study, said friends and family influenced health for the better by offering a ‘calming touch’ or by helping people find meaning in their lives.

The researchers looked at data from 148 previously published studies that measured people’s social networks and tracked their health for an average of seven and a half years.

The data did not show whether people were in ‘positive’ or ‘negative’ relationships – simply the number of people they were in contact with regularly.

The authors of the study believe the health benefits of positive friendships could be even stronger. ‘The data simply show whether they were integrated in a social network.