Designer labels do nothing for me, unfortunately. I have yet to discover how wearing a particular brand name can make me a better person.

In fact, considering the prices of designer gear, I hope to pass this little foible on to my offspring before they reach their teens.

If all else fails, they'll have to make do with home produced logos such as "I'd even look good wearing a bin liner" or, more simply, "A Label".

But perhaps I'm missing the point. For most of us, identity is bound up with what we believe others think of us.

Teenagers, in particular, feel the need to be accepted and fit in with trends.

These include food fads at a time when profound physical changes are occurring and when a nutrient-dense diet is required, to support growth and the inevitable hormonal mayhem.

Teenagers' increasing independence means more meals are eaten away from home and replaced by snacks and fast food.

There may be lifestyle changes, such as less sport and more computer-based activities, as well as experimentation with alcohol and nicotine.

Many children are having to deal with conflict at home and school, are worried about the future or are overly concerned with body image.

Consequently, eating disorders are rising steadily.

A common m i s t a k e teenagers make is to rely too heavily on refined carbohydrates (bread, pasta, pizza) and sweets, which are rapidly absorbed, causing energy dips and mood swings.

Even more alarming is the amount of fizzy drinks consumed more than one in eight teenagers is drinking at least 22 cans of cola per week.

Obesity, serious tooth erosion , diabetes and osteoporosis are only some of the potential risk factors.

One wonders how far diet is related to crime and delinquency.

The protein content in the diest of a teenager can be low and nutritional deficiencies are common, in particular of the minerals calcium, zinc, chromium, manganese, magnesium, iron, selenium and vitamins A, B, C and E.

An appropriate multivitamin and mineral supplement is highly recommended for development.

So are essential fatty acids, found in oily fish, nuts and seeds, which help to promote brain function and support immunity.

If you have a toxic teenager who is in no mood to listen to your well-intentioned advice, take them to a nutritionist.

They will explain how to achieve shiny hair, clearer skin and better concentration.

Meanwhile, don't nag but provide an environment in which nutritious snacks and wholesome meals are readily available, so that your teenager can make the right choices.

Instead of a steady stream of crisps, biscuits, ice-cream, toast and marmalade, offer fruit sorbet, home-made popcorn, baked potato skins plus dip or a slice of watermelon with cubes of feta cheese.

It needn't be fussy or complicated and with the variety of foods and cookbooks on display, there really is no excuse to fall back on junk food.