Obesity lies at the heart of a host of serious medical problems including diabetes, heart disease, strokes and severe joint damage. Despite the World Health Organisation classifying obesity as a disease, experts fear not enough is being done.
Behind the growth in obesity is a combination of a more sedentary lifestyle and a high fat, high sugar diet which causes us to pile on the pounds.
"One in six people are now obese - three stone or more over their correct weight - and probably 30 per cent of the population are simply overweight." says Dr Nick Finer, a consultant specialising in obesity who works at Addenbrookes, Cambridge and Luton and Dunstable Hospital.
These figures have doubled in the last 10 years, and Dr Finer, who appears in a BBC Horizon programme this week, predicts that if trends continue everyone could be clinically obese within 50 years. The cost implications are also great. Obesity now eats up 6 per cent of the US health budget, and an estimated 2 per cent of the UK's - equivalent to the amount spent on treating cancer or all tobacco-related diseases.
While two new drugs are likely to come on the market within the year, designed to reduce fat intake while increasing energy expenditure, Dr Finer called for government to take immediate action to curb the problem.
He also wants the medical profession to recognise the seriousness of the situation. "If you look at the US, whose trends we tend to follow, the majority of the adult population, more than 50 per cent, are overweight or obese," says Dr Finer "It is a terrifying scenario."
Horizon "Fat Cats Thin Mice" is on BBC2, Thursday 6 March at 9pm.Reuse content