It's official: Marriage DOES make you fat... Men and women twice as likely to be clinically obese after tying the knot Last updated at 3:23 AM on 20th March 2010 It is often said that marriage makes you contented. Now scientists have discovered the extent to which that happiness translates into extra pounds around the waist. Married men are three times as likely to suffer from abdominal obesity - or belly fat - as single men, their report shows. Married women are twice as likely to have those problems as those who remain unmarried. The Hellenic Medical Association for Obesity concluded that abdominal obesity was the worst health problem among married couples after conducting a survey of 17,341 people aged between 20 and 70. Tight squeeze: Abdominal obesity - or belly fat - is the worst problem among married couples Association president Dimitris Kiortsis joked: 'Next time you are wondering what wedding present to buy a friend, perhaps a slimming course might be a good idea.' The researchers blamed married couples' expanding waistlines on the amount of time they sit together watching TV and eating. And they claimed that dwindling sex lives cut the number of calories that wedded couples lose with exercise. As the findings were announced at a conference in Athens yesterday, Professor Kiortsis, an obesity expert, said married couples order takeaways and exercise less often than before. Unmarried people often spend a lot of time keeping fit and making themselves attractive to find a partner. 'But once they get married they let themselves go,' he added. 'The need to hunt for a partner is reduced.' But it wasn't all bad news for married couples. Stress and anxiety is reduced in a good marriage,' said Professor Kiortsis. 'There is less smoking and therefore one's appetite increases.' Last year, a report estimated that 22 per cent of newlywed women put on weight within a year of the ceremony, with the average gain being a stone-and-a-half. More than half of those who took part in the survey of 3,000 married women, sponsored by yoghurt-maker Yakult, said they no longer worried about their appearance and weight after their wedding day.