Question

My 18-year-old daughter is slim, very fit and sporty, has honey-toned skin, is 5ft 7in tall, weighs 8st 7lb, and is a healthy eater. She moisturises every day and doesn't drink much. She's very healthy overall. She's spent the last six months on a gap placement in Vancouver and though she was active and ate healthily, she has put on about half a stone. In the past two months she has noticed some very ugly, purplish stretchmarks at the tops of her thighs - horizontal and towards the front of her legs. She is extremely upset and worried about a) how they came to be there and b) how to get rid of them. Like all girls her age, she loves to wear short skirts and bikinis, etc. What would you advise?

The dermatologist

Emma Edmonds

Stretchmarks affect more than half the population and can appear if there is rapid stretching of the skin. They commonly occur on the abdomen and breasts of pregnant women, in adolescents undergoing a growth spurt and in those who are overweight. Less commonly, they may be due to a medical condition such as Cushing's disease (when the body produces too much cortisol) or as a side-effect of medications.

The first thing I'd do is take a baseline blood test to make sure there is no medical problem. Provided all is well, I'd recommend a vitamin A-based retinoid cream or silicone gel, as these can help the appearance of stretchmarks. Fake tans can provide camouflage, while dermabrasion, chemical peels and laser surgery can be expensive, with only variable success. Your daughter is unlikely to get rid of the marks completely; keeping her weight constant is probably the best protection against new marks.

· Dr Emma Edmonds is a dermatologist for the British Skin Foundation (www.britishskinfoundation.org.uk)

The patient

Rachel Morgan

My advice to your daughter would be to get things in perspective. It's upsetting to get stretchmarks when you're young, but I bet that she's not the only one of her friends who has them, and it sounds like she has only limited stretchmarks at the moment. My view is that they're just one of those things, like cellulite, that millions of women have to put up with.

I was in my early twenties when mine first started cropping up all over my stomach, between my thighs and around the front of my legs. I'm quite pale skinned and the stretchmarks were bright red. But even then, I didn't lose my confidence. I didn't try any creams because I felt that, for good or bad, my stretchmarks were just part of me, but lots of my friends tried all kinds of lotions and potions. Maybe your daughter can do this if she wants to feel like she's doing something to help herself. But time is the best cure - mine are now silver and hardly noticeable.

· Rachel Morgan, 35, is a mother of two from Penarth, South Wales

The dietician

Jacqui Lowdon

Stretchmarks are common and are usually caused by rapid weight gain or loss, and height growth, particularly in younger teenagers. If putting on half a stone contributed to her stretchmarks, losing the weight quickly will do similar damage. Your daughter sounds like she is on the slim side, so I'd advise her to maintain her current weight; but if she is determined to lose the 7lb, make sure she does it slowly and steadily, to allow her skin to retain its elasticity. She should also drink plenty of fluids to keep her skin hydrated - at least two litres a day.

A diet naturally rich in vitamins A, C and E will be good for her skin, as these are antioxidant vitamins which help prevent free radical formation and damage to the skin. Avocado, nuts, whole-grain cereals, pulses, citrus fruits and carrots are all good sources. If your daughter also avoids processed foods, and eats five portions of fruit and veg a day, she will minimise any future damage to her skin.

· Jacqui Lowdon is a registered dietician at the University Hospital of Wales, Cardiff

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