More than a quarter of women say they put on weight after moving in with their male partner - because they eat more unhealthy foods, like takeaway pizza, curries and fish and chips.

A survey of 1,000 Brits - 500 men and 500 women - found that 27 per cent of the women polled said that within weeks of moving in with their partner they started eating a less healthy diet, snacking on junk food and takeaways.

They blamed men for the change in their diet, saying they had a 'negative effect' on their eating habits and ended with them putting on weight.

The remaining 73 per cent said that men made little or no difference to their diet after moving in with them.

A survey of 1,000 Brits - 500 men and 500 women - found that 27 per cent of the women polled said that within weeks of moving in with their partner they started eating a less healthy diet

Conversely, 40 per cent of men polled said that women had a 'positive impact' on their diet when they moved in and said they ended up eating less junk food food when living together, with the remaining 60 per cent saying it made 'little of no difference' to their diets.

The research, by self-storage firm Space Station, also found that just one-in-10 couples said their sex lives improved after their partner moved in.

A total of 37 per cent said they had less sex since moving in together, with the remainder saying their sex lives remained unchanged.

One in ten couples admitted to rowing over a lack of space in the home, with over half of men saying their partner took up too much space compared to just a fifth of women who said their man took up 'too much space'.

Claire Grant, 31, of St Albans, Herts, said she ended up 'snacking all the time' and eating takeaways after moving in with her partner in the summer.

She said: 'I moved into my partner's home and found that he had this snack cupboard and endless takeaway menus.

'When I was living by myself I used to restrain myself and eat pretty healthily, but since moving in with my partner I've just gone crazy, eating crisps, nuts and ordering takeaways three times a week.

'I've probably put on half-a-stone in the past few months, so I'll have to get down the gym in the New Year.'

Hypnotherapist Dipti Trait said: 'Weight gain and loss in human beings in a lot of cases is inextricably linked with our behaviour and habits.

When we as human beings feel settled, we relax

'When we as human beings feel settled, we relax. This feeling of relaxation can extend into other areas in our lives.

'So, in the case of feeling secure in our relationships, we can begin to relax with our behaviours, such as our eating habits.

'This can explain why when we are in relationships that feel comfortable, we tend to enjoy this feeling of being secure and our habits become more routined and settled in their patterns.

'Habits are just actions and choices we make without really thinking too hard, so when we feel comfortable in our lives because everything is ticking along nicely, the brain goes into a mode of routine, and these routines often go unnoticed, because they become normalised.'

Vlatka Lake, of Space Station, said that although moving in together was an 'exciting time' many people ended up 'eating less healthily'.