My 10-year-old son is very overweight - he's 5ft 2in and weighs 13st. He's always had a good diet at home, but has a sweet tooth and buys junk food every day. As he's become bigger, he's started getting bullied, which makes him turn even more to comfort food. He used to love football, but he never wants to run around these days. Because I have two other children (neither of whom is overweight), I do have some crisps and biscuits in the cupboards and I have considered locking these to stop Peter snacking, but I'm worried this may make him feel besieged at home as well as school. I'm trying to find a way to make him understand the damage he's causing his body, but I'm failing miserably. Can you help?

Carol Gittings
The mother

My son Ross started gaining weight at six, and was bullied at school from a young age. Last year, aged 14, he was 5ft 6in and 18 ½ stone. I've tried everything over the years: GPs, consultants, counselling, even Great Ormond Street, but in the end it came down to the same thing - everyone just told him to change his eating habits. But the key is working out why these children are unhappy and helping them through it. By last summer I was petrified that Ross was going to get diabetes or heart disease, as his BMI was twice normal levels. So I booked him into a weight-loss camp for five weeks. An average day consisted of lifestyle lessons, various activities and four hours of exercise. Ross came home 14lb lighter and 'walking taller'. The vicious cycle was broken: he now understands that he needs to respect his body and exercise. He still has a long way to go - but we're finally getting somewhere.

· Carol Gittings is a school administrator and a mother of two from Hertfordshire

Michael Bruch
The psychotherapist

Eating food for comfort is an issue when this becomes a substitute for coping with problems. Your son may have learned to eat sweets to comfort himself; he may need help to improve his self-control skills, and he should never be rewarded with such foods, if possible. This may involve not stocking food he craves or locking it away, and also the encouragement of healthy snack options. Ideally such rules would apply to all children and yourself. A psychologist who specialises in cognitive behavioural therapy can help unravel your son's problems. The British Association for Behavioural and Cognitive Psychotherapies (01254 875 277) has a list of accredited practitioners. I'd like to see the whole family engage in behaviours that will help your son. It's also important to reactivate his social life and encourage him to participate in school sports.

· Michael Bruch is a consultant cognitive behavioural psychotherapist at University College London who specialises in children and adolescents and eating disorders

Paul Gately
The weight-loss expert

You are obviously aware of your son's eating issues, which is a good start. Now think what you can do to change his attitude to food. You are in charge of the home environment, and you have more control than you realise. I think you're right not to lock the food cupboards, as this will make your son feel guilty and a failure. Let crisps and biscuits stay, but in moderation, and make sure the fruit bowl is full so your kids can freely snack. This way you are limiting junk food, but the kids are still free to make their own (limited) choices. Over time, your son's attitude to food should improve. Also think about incentives but without using food - a family trip out bowling, a new football strip, a hug can all be just as effective as a pack of sweets. Finally, implement fun family days that involve activity so that he burns calories while he's having a good time.

· Paul Gately is professor of exercise and obesity and director of Carnegie Weight Management at Leeds Metropolitan University (0113 283 2600)

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