One in 10 six-year-olds is obese. The total number of obese children has doubled since 1982. On present trends half of all children in England in 2020 could be obese. So is this just harmless puppy fat or something more serious?
What is the problem?
If a child becomes obese their body processes can change. Some of these may be difficult or even impossible to alter in adulthood.


Fat cells

Fat cells are laid down in the first few years of life. If fat is stored quickly, more fat cells are created. So an obese child can have up to three times as many as a normal child. Eventually, fat cells stop multiplying and an adult has a fixed number for the rest of their life. The existing cells simply swell or shrink to accommodate more fat.

The amount of fat the body wants to store is thought to be proportional to the total number of fat cells. So if you were overweight as a child, your body is programmed to carry more fat. This doesn't mean that you can't lose weight through diet and exercise, but it will be harder.
Health problems for kids
Few health problems are observed in obese children. But they may develop conditions that cause problems later in life, such as high blood pressure.
They may also suffer from 'sleep apnoea'. When this happens, soft tissue in the throat blocks the airways during sleep. This can stop their breathing for up to a minute. This process can happen hundreds of times a night, leading to cardiovascular disease, memory problems, headaches and fatigue.
Diabetes risk
Some obese children may develop type II diabetes. Normally this condition only starts much later in life. When it strikes, the body stops being able to process sugar properly and the cells are starved of energy. Type II diabetes cannot be cured, but it can be treated. It may lead to complications such as nerve damage, heart disease, kidney disease and blindness. Children with this condition will have to live with it all their lives, increasing the chance of complications.

Negative body image can cause depression and social problems - overweight children are often teased. Low self-esteem may not directly affect physical health, but it is the biggest problem encountered. It may even lead to 'comfort eating', exacerbating the situation. If our culture placed less emphasis on the 'perfect body', then at least one set of issues associated with obesity would vanish.
What treatments are available for obesity?

What Treatments Are Available?
Our feelings of hunger are controlled by a part of the brain called the 'hypothalamus'. This takes its cue from a number of different chemical messengers, or hormones, circulating in our blood.
New drugs
Current weight-loss drugs are mainly amphetamine based. They increase the amount of noradrenaline and dopamine hormones in the blood, lowering hunger levels. However, they are not suitable for long-term use and side effects can include high blood pressure, anxiety and restlessness.
New drugs are being developed that may give greater weight loss with fewer side effects. Recently, scientists have focused their attention on the interaction between fat and hunger. Fat produces a hormone called 'leptin', which turns off the feeling of hunger in the brain.
So if we have high fat levels inside us, our appetite is suppressed. But when they drop we become hungry. Although the link between leptin levels and hunger is not simple, scientists may be able to develop drugs that interfere with this cycle.

One research project involves genetically engineered mice with a faster metabolic rate. So however much they eat they still stay lean, burning up the energy as heat rather than laying it down as excess fat. This research could help make new drugs for humans.


Lifestyle changes
New drugs may help people to lose weight, but the problem is keeping it off. Most people who lose weight on a calorie controlled diet put it on again. Only 5% of obese people manage to keep their weight down.
What is required is a complete change in lifestyle. More exercise, a healthier balanced diet and realistic expectations can help make the change permanent. To become more healthy doesn't require huge weight loss.
For more information about diet and exercise visit BBC Health.
How do you stop your child getting too fat? Professor Jane Wardle, health psychologist, gives her advice on childhood obesity