The researchers from the University of Alberta conducted tests on young rats, and found when the animals were given low-calorie versions of foods they overate regardless of whether they were lean or obese.

The researchers suspect that low-calorie versions of usually high-calorie foods disrupt the body's ability to use taste to regulate calorific intake and they say diet foods are probably not a good idea for growing youngsters.

Lead researcher Professor David Pierce says on the basis of the study findings, it is better for children to eat healthy, well-balanced diets with sufficient calories for their daily activities rather than low-calorie snacks or meals.

In the study the rats were fed either sweet or salty high-calorie or low-calorie gelatin cubes over the course of 16 days.

The researchers found that young rats given low-calorie foods began to overeat during their regular meals while older, adolescent rats also fed diet foods did not show the same tendency to overeat.

The researchers believe this occurred because the older rats, unlike the younger rats, were able to rely on a variety of taste-related cues to correctly assess the energy value of their food.

The younger rats learned to match tastes usually associated with food high in calories with low-fat alternatives, and so carried on eating to try to get their calorie count up when in fact it had already reached a healthy level.

Professor Pierce says the research highlights the importance of promoting a balanced diet and exercise as the best ways to keep children fit and healthy and says diet foods are not a good idea for growing youngsters.

Obesity is a significant risk factor for both type-2 diabetes and cardiovascular disease, and soaring rates present an increasing public health problem.

Experts say the study reinforces the need to encourage healthy eating habits in children from early in life by avoiding sweetened beverages, processed food and fast food.

They also recommend limiting TV time, fitting physical activity into the everyday routine and eating together as a family.

The study appears in the journal Obesity.

10 YEARS % CHANGE Type of cancer 10 year % change* Number of newly diagnosed cases, 1994 Number of newly diagnosed cases, 2004 % of all cancers, 2004 Malignant Melanoma 43% 5,783 8,939 3.1% Oral 23% 3,696 4,769 1.7% Uterus (womb) 21% 5,018 6,438 2.3% Kidney 14% 5,636 7,044 2.5%

*Based on European age-standardised rates per 100,000

Read the full incidence report online.

SunSmart campaign

SunSmart is the UK's national skin cancer prevention campaign, commissioned by the UK Health Departments and run by Cancer Research UK. The SunSmart messages are:

Spend time in the shade between 11 and 3. The summer sun is most damaging to your skin in the middle of the day. Make sure you never burn. Sunburn can double your risk of skin cancer. Aim to cover up with a t-shirt, hat and sunglasses. When the sun is at its peak sunscreen is not enough. Remember to take extra care with children. Young skin is delicate. Keep babies out of the sun especially around midday. Then use factor 15+ sunscreen. Apply sunscreen generously and reapply often.

...Also report mole changes or unusual skin growths promptly to your doctor.

Find out more at www.sunsmart.

Open Up to Mouth Cancer campaign

Open Up to Mouth Cancer is a national campaign commissioned by the Department of Health and run by Cancer Research UK. The aim of the campaign is to raise awareness of mouth cancer and methods for its effective prevention and early detection, especially among at-risk groups. The early warning signs of mouth cancer include:

an ulcer or sore in your mouth a red or white patch in your mouth an unexplained pain in your mouth or ear an unexplained lump in your neck a sore or painful throat a croaky voice or difficultly swallowing

See your doctor or dentist if any of these symptoms last longer than three weeks.

Reduce the Risk campaign

Research suggests that around half of all cancers could be prevented by changes to lifestyle. Cancer Research UK's Reduce the Risk campaign highlights five ways you can lower your cancer risk:

Stop smoking - It's the best present you'll ever give yourself Stay in shape - Be active and keep a healthy body weight Eat and drink healthily - Limit alcohol and choose a balanced diet with plenty of fruit and vegetables Be SunSmart - Protect your self in the sun and take care not to burn Look after number one - Know your body and see your doctor about anything unusual. Go for screening when invited

For more information about the campaign visit www.reducetherisk.

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