Sir

David A. King and Sandy M. Thomas in their essay 'Big lessons for a healthy future' (Nature 449, 791; 2007) describe how, in Western societies, “growing recognition of how science can contribute to health, well-being and the economy” is leading to governmental attempts to control public health. Their Foresight study suggests that by 2050, in the United Kingdom, about 60% of men, 50% of women and 25% of children will be obese, and that the associated chronic health problems will cost an additional £45.5 billion (US$93 billion) a year. To combat this, the authors propose a strategy similar to that used for climate-change policy, in which six chief advisers (and their entourages) of government departments developed a 'top-down' strategy.

Such a paternalistic approach is reminiscent of past attempts to eradicate cholera and smallpox by better sanitation, housing and vaccination. However, today's lifestyle-related diseases, such as obesity, type-2 diabetes mellitus and cardiovascular disease, are different. They develop slowly, in response to chronic food intoxication and lack of exercise, causing a long-lasting imbalance between excess energy intake and insufficient energy expenditure. And they require a different approach.

Paternalistic health-care systems will be of little avail because they fail to activate the individual's motivation to care continuously for his or her own health, which is necessary for success. To secure such motivation, there would have to be annual financial incentives for those complying, with set targets as to body weight and physical strength. Such incentives could be tax breaks, or a partial annual cash refund of private health-insurance premiums. The aim would be absence of lifestyle-related disease at the age of 60. An addressable target group for such incentives could be people aged 35–55 who care for children and/or elderly family members, as additional pressure from their dependants might help to secure compliance with health targets.