Q My wife’s put on a lot of weight in the past ten years. It is affecting our love life as I no longer find her attractive. Any tips that might bring back the magic?

DR THOMAS STUTTAFORD

A Almost as many men are sexually repelled by the exceptionally thin as are attracted by women who could have modelled for Rubens. And few overweight women – who could be described as fat by those concerned about such trivialities – are without a partner.

The object of partialism, an obsession with one part or aspect of a partner’s body, has often been determined by the environment in which the partialist has grown up. In many parts of the world, burgeoning curves, even obvious obesity, is seen as a sign of health and wealth and, therefore, are highly desirable. In parts of Africa the proverb says that a thin daughter is not worth many cows. There, a thin woman may be betraying a sign of disease so that young men have been programmed to choose plumper wives whose figure not only gives promise of pneumatic bliss, and of the ability to have children, but are also likely to be around to care for them.

In the developed world, partialism can be focused on knees, lips, ears, hair colour or some other less obvious part of the body such as the nape of the neck or shoulder blades. Some men similarly are obsessed with weight.

Most Western men have either a marked preference for breasts or bottoms. The instinct that determines this is essentially the same. Breasts developed in size and sexual appeal once Homo sapiens started to walk on two legs. As a result breasts became more visible, whereas bottoms, which most four-legged animals find irresistible, were less prominent.

We need to know whether you married a svelte woman who put on weight to an extent that you never thought possible, or whether she was always well covered and is now obviously overweight. Anyone whose bride is curvaceous should expect after ten years and a child or two to have some changes.

By now your marriage should have reached the stage of friendship rather than pure lust. You should be more interested in her personality rather than being obsessed about her weight. Is it that you are not, in reality, worrying about her appearance but rather her obvious loss of youth and that you feel this reflects on you? Enjoy her company and don’t give a damn if she is a size 16 or a size 12. How have the years treated you? Does your wife have to accept an expanding waistline and receding hairline? Remember: no one holds back the tide of ageing for ever.

Your problems, such as they are, would be solved if you could persuade your wife to lose weight. But people of either sex can put on weight while still having a pitifully meagre diet. Don’t be judgmental. Instead, cooperate with her and help her to find a slimming club.

Being turned on or off by excessive weight is neither a male nor female characteristic. It is hard on the overweight partner, but the cuddly should take heart. A colleague of mine, who has always been a size 10, has occasionally had the equivalent of a size 20 boyfriend. She says that variety is the spice of life. Furthermore, she finds it comforting to enjoy the company of men who are unlikely to be too concerned about her physical flaws. Plump partners with Rubensesque rolls of flesh often try harder to please. They also enjoy the other good things in life, such as oysters, champagne and meringues.

Dr Thomas Stuttaford, the Times doctor, spent many years working in a genitourinary clinic

SUZI GODSON

A You can’t. The words “you” and “fat” should never be used in the same sentence when addressing any woman with whom you intend to have an ongoing relationship. Stating the indisputably obvious might make you feel better, but take it from me, your wife already knows she is fat, and she hates herself for it. Every morning when she wakes up she feels the rolls of fat around her midriff and berates herself. As she showers and washes between the folds of her flesh she loathes herself a little more. As she brushes her teeth, she spits toothpaste at the jowly bloater that stares back at her from the mirror and then she dresses in one of two outfits, both black, that she thinks make her look fractionally thinner before heading to the kitchen to begin her miserable daily battle with fat, carbohydrates and calories.

If it makes her so unhappy, why doesn’t she do something about it, you ask? It’s a fair point. Going on a diet and taking some exercise should be a no-brainer for all fatties, but unfortunately, the connection between intellectual masochism and physical motivation is not straightforward. Your wife may hate the size of her ass, but that won’t necessarily be enough to get her off it. It is partly to do with unrealistic goals. Instead of accepting that it took her ten years to put the weight on and it might take her five to get it off, she loses heart after five weeks on a diet and winds up back where she started, except that this time she feels like a failure, too. The fact that you don’t feel attracted to her has probably not gone unnoticed, but it may be something of a relief to her. Overweight people rarely feel comfortable about physical intimacy.

When Martin Binks, a clinical psychologist and director of behavioural science at Duke University, North Carolina, studied 1,210 overweight people, he found that four out of every ten reported physical problems with sex. Both men and women suffered from lack of sexual desire and enjoyment along with hampered performance. And many reported avoiding sex entirely.

So what can you do to help? Emma Hetherington, the head of programme development at WeightWatchers, says: “Don’t dwell on your own feelings; give her some practical support instead.” You may also need to accept a modicum of responsibility. If she’s cooking steak and chips for you every night, chances are she’s eating steak and chips, so if she is going to diet successfully, you will need to make changes, too. The same goes for exercise. If you want her to stick with an exercise regimen, making dinner or volunteering to put the kids to bed will make it easier for her to find the time to get to the gym. Better still, go with her. A study of more than 31,000 men carried out by the Harvard School of Public Health found that men who were physically active had a 30 per cent lower risk for erectile dysfunction than men who did little or no physical activity. And a study by the University of British Columbia found that 20 minutes of exercise improved sexual response in the female participants compared with no exercise at all.

Once your wife gets started she will find that success is self-propelling. And the good news for you is that the Duke study indicates that weight loss of as little as 10 per cent boosts confidence and improves sex.

Suzi Godson is the author of The Sex Book (Cassell, £16.99) and The Body Bible (Penguin, £16.99)

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