- 29 October 2008
- From New Scientist Print Edition.
AS THE defining epidemic of a modern age notable for overconsumption and excess, obesity is hard to beat. The increased availability of high-fat, high-sugar foods, along with more sedentary lifestyles, has helped push the number of obese people worldwide to beyond 400 million, and the number of overweight to more than 1.6 billion. By 2015, those figures are likely to grow to 700 million and 2.3 billion respectively, according to the World Health Organization. Given the health implications - increased risk of heart disease, stroke, diabetes and some cancers - anything that helps people avoid piling on the pounds must be a good thing, right?
Those who agree will no doubt welcome the growing success of researchers striving to develop "diet pills" that provide a technical fix for those incapable of losing weight any other way.
Last week a study published in The Lancet showed that tesofensine, which works by inducing a sense of fullness, is twice as effective as any other drug at enabling patients to lose weight(see "Whirlwind week for dieters").
There's no question that advances such as this are good news for those with a strong genetic predisposition to obesity. But for the rest of us it is dangerous to see treatment as a more effective solution than prevention.
There are several reasons for this. For a start, the traditional ways of maintaining a safe weight, such as limiting what you eat, increasing consumption of fruit and vegetables and taking more exercise, are beneficial for our health in many ways.
Second, overindulgence in fatty foods has implications for the entire planet. Consider the deleterious environmental effects of the rising demand for meat. As demonstrated in our special issue on economic growth (18 October, p 40), technological fixes will not compensate for excessive consumption.
Third, interfering with the brain circuits that control the desire for food can have an impact on other aspects of a person's personality and their mental and physical health.
We need two approaches: more research into the genetics of obesity to understand why some people are more susceptible, and greater efforts to help people avoid eating their way to an early death.Cynics will say we've tried education and it hasn't worked. That is defeatist: getting people to change their behaviour takes time and effort, held back as we are by our biological tendency to eat more than we need, and by the food industry's ruthless opportunism in exploiting that.
Drugs will be the saving of a few - as a last resort. But the global obesity problem is one of lifestyle, and the solution must be too.