Marriage makes you fat

A recent study found that married couples are more likely to put on weight. But there are ways of losing the weight gained after you have tied the knot.

Professor Lawrie Bailyn from the University of Western Australia has completed a 16 year study that showed when couples got married, not only did they get a new partner they also needed to get a new wardrobe.

"Men were more likely to be fatter and more likely to be less physically active," Professor Bailyn said.

On average, men gain around 8kg between the ages of 18 and 25. But if they are married or living in a long term relationship that figure increases to 10kg.

Married women are around 1kg heavier than their single counterparts.

Robin and Ken Atkins have been married for 18 years. They said over the years some bad eating habits, combined with a slowing down of their social lives led to them both carrying a little extra weight.

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Body language expert Alan Pease said some relationships deteriorate as partners gain a little weight.

It could especially bad news for women. Mr Pease said men are biologically attracted to women who seem healthy and able to produce offspring.

But women are biologically wired to be attracted to men who are good providers and looks are not as big an issue.

"Men are looking for health which is reflected in skin, shape and youth so that women can carry on their genes," Mr Pease said.

"Women are looking to men for resources, that is, his ability to provide," he added.

That means even if a guy puts on a little weight while married, his wife is more likely to overlook it, as long as he is still ambitious and a good provider.

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Mr Pease said most of the weight gain probably occurs because both partners get a little too comfortable.

"Just as people should be working on their relationship, they need to be working on a constantly healthy lifestyle, keeping active and eating a healthy diet," Professor Bailyn said.