Suzi Godson

No. Obviously you will need to take them off at some point to wash them, but as things stand, Lycra is fairly low on the list of hazardous materials. Yes, your interest in wearing tight shiny leggings probably indicates the start of some kind of fabric fetish, but so what? Far worse to be 16 and obsessed with wearing hooded sweatshirts and carrying kitchen knives.

People don't really understand fetish and that's why they are scared of it, but the vast majority of fetish is harmless. In fact, one of the reasons it is so difficult to establish the prevalence of fetish in our society is because it rarely interferes with a person's life to the extent that they need treatment.

In 1983 the clinical psychologists A.J.Chalkley and G.E.Powell reviewed 20 years of discharge records from the Bethlem Royal and Maudsley hospitals in London and estimated that the incidence of fetishism among the psychiatric population to be 0.8 per cent.

Their study, published in the British Journal of Psychiatry, revealed that the vast majority of fetishes involved items of clothing, including underwear and hosiery (58.3 per cent), rubber and rubber items (22.9 per cent), footwear (14.6 per cent), leather and leather items (10.4 per cent), and soft materials and fabrics (6.3 per cent).

But perhaps the most interesting aspect of their research was that of the 48 cases reviewed, only 14 patients said their fetish was why they had sought or needed psychiatric help.

If Chalkley and Powell were doing their research today they would head straight to fetish central, the worldwide web. Whether you want men in tights or women in chains, the internet is awash with so much fetish that 0.8 per cent is surely a gross underestimation. In the same way that bondage and shoe fetish have informed and filtered into mainstream fashion directions, American Apparel's (www.store.americanapparel.co.uk ) brightly-coloured spandex lamé leggings are surely the high street interpretation of Lycra fetish.

As fetishes go, getting a kick out of wearing cycling gear is a manageable quirk and, given your age, one that you may well grow out of. At 16, virtually everything has sexual potential anyway.

I suspect that your main concern is how friends and family would react if they found out. Teenagers get freaked out about anything that marks them as different, or makes them stand out in a crowd, yet at the same time, they all recognise that individuality is currency. But whether they are passionate about politics or performance, whether they are fashion forward or backward, whether they wear Lycra or ball gowns, the boys and girls who are brave enough to do their own thing and individual enough to carve out their own identity are always, eventually, rated for their originality.

The first time you go out wearing Lycra pants your friends might tease you. The fourth time you go out wearing Lycra leggings someone will ask you where you got them because they think they'd like a pair too. By the time Lycra for boys is a fashion trend, you'll probably have moved on to velvet.

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

Dr Thomas Stuttaford

From your letter it would appear that you may have a tendency to be attracted by the pursuit of two different aspects of sexuality. The Lycra leggings suggest some degree of fetishism whereas your interest in women's clothes - especially as they are your mother's - hints at transvestism.

I expect that you'll have read enough on the internet or in sexual manuals to have a sound knowledge of both transvestism and transsexualism and the relation between them and their possible link to fetishism. Transvestism is a propensity to dress in the clothes traditionally worn by the other sex while transsexualism can occur in either sex. It is the condition in which someone is convinced that a terrible mistake has occurred and that they are the victim of having a female or male mind in the body of someone of the opposite sex. They agree that they are physically male and even that their chromosomes confirm this, but this doesn't shake their determination that something needs to be done to realign their physique to their personality.

Cross dressing - transvestism - seems to be more common in the art world. This may be more apparent than real and only reflect an environment in which unusual or flamboyant dress will be considered Bohemian. The potter Grayson Perry typifies a transvestite who is open about his desire to cross-dress, but is happily married, has a daughter and is determinedly heterosexual.

In other occupations people make great efforts to hide any tendency to cross- dress and it is discovered only when a secret cache of clothes is found. Other transvestites are exposed when a partner returns home unexpectedly to find their spouse dressed in clothes of the other sex. Often they are found in front of a mirror as frequently the clothes are a masturbatory aid. In other instances people say that cross-dressing makes them feel relaxed and safe. Some may be able to make love to a partner only when they are wearing or touching clothes belonging to the other sex.

Fetishism is a recurrent, intense sexual urge, which has been obvious for at least six months, to use a non-living object as part of a sexual ritual. It usually begins in adolescence, affects far more men than women and is only rarely a feature of homosexuality. Fetishists favour rubber, Lycra, silk, fur or metallic materials. Objects that are frequently used are women's underclothes, including bras, pants and stockings, and any other classically female garment.

Fetishism has to be distinguished from partialism, an equally intense, almost obsessive, interest in some body part, not always with an obvious sexual connotation. I remember one distinguished, apparently archetypal army officer who couldn't resist women with dimpled knees.

Are your interests unhealthy? If you could have full sex only when wearing Lycra leggings, you may have a problem with partners. However, adverse effects on your health would occur only because of the psychological strain of keeping this a secret. It is unlikely at your age that tastes will change. You may well need an understanding partner.

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

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