Dear Gary Lineker, Congratulations on winning the Food Commission's Greedy Star award after earning more than £5 million from the Walkers Crisps adverts.

Much deserved, I'm sure, as your two-year ad campaign has helped "sell enough crisps to cover the whole of Holland", according to a spokesman from Walkers.

But there's no need to be defensive about your achievements and go blaming the parents.

You say it is lack of exercise, not junk food, that is making children overweight.

Well, I must agree, people are far too sedentary these days.

The reason they have no get-up-and-go is because they are feeling sluggish from a diet consisting of processed food high in salt, sugar and dangerous fats.

A packet of your favourite salt and vinegar crisps contains one gram of salt, which is half the maximum recommended total daily intake for a six-year-old. All in one handy little snack.

As you are not a nutritionist, you are hardly expected to know that excess salt causes water retention and raises blood pressure.

Or that the monosodium glutamate, flavourings and colourings in crisps can trigger off headaches and disruptive behaviour - particularly if children are lacking in vitamins and minerals.

You may be aware that one third of each packet of crisps is pure fat.

Don't get me wrong, we do need to eat fat, but did you know the wrong type can seriously undermine our physical and mental health?

And the hefty dose of fat provided by those crisps you've been promoting is almost all - you've guessed it - of the wrong type.

I spoke to Dr Alex Richardson, senior research fellow at Mansfield College and the Department of Physiology, University of Oxford.

There is much more at stake here than weight gain.

Dr Richardson explains: "Children no longer consume enough of the vital omega 3 fats contained in oily fish which are crucial for brain development and function."

"If our intake of these complex fats is low, the body can build its own essential fats from simpler omega 3 fats found in some nuts, seeds and green vegetables.

"But this conversion process is clobbered by our high intake of hydrogenated and saturated fats as found in processed convenience foods and snacks.

"The upshot of it all is we are seeing a huge rise in behavioural and learning disorders in children as well as mental health problems in adults. Another common fall-out from a lack of essential fats is low immunity and allergies."

Dr Richardson will be speaking about which fats can make you smart and which can make you stupid at the Children's Mental Health - Feeding The Next Generation conference in London on October 9.

For details, call 0870 161 3505 or visit I have great pleasure in offering you, Gary, a complementary ticket.

You say parents are being manipulated and treated like idiots by health groups. Perhaps you'd like to consider how certain food companies are manipulating gullible sports stars into losing their good reputations by endorsing junk, while the companies themselves are laughing all the way to the bank.

Martina is a qualified nutritional therapist at the Crescent Clinic of Complementary Medicine, 37 Vernon Terrace, Brighton. Tel: 01273 202221 or email: