- Andrew M Prentice, head of energy metabolism groupa,
- Susan A Jebb, research scientista
- MRC Dunn Clinical Nutrition Centre, Cambridge CB2 2DH
- Correspondence to: Dr Prentice.
- Accepted 24 May 1995
The prevalence of clinical obesity in Britain has doubled in the past decade. The Health of the Nation initiative has set ambitious targets for reversing the trend in recognition of the serious health burden which will accrue, but efforts to develop prevention and treatment strategies are handicapped by uncertainty as to the aetiology of the problem. It is generally assumed that ready access to highly palatable foods induces excess consumption and that obesity is caused by simple gluttony. There is evidence that a high fat diet does override normal satiety mechanisms. However, average recorded energy intake in Britain has declined substantially as obesity rates have escalated. The implication is that levels of physical activity, and hence energy needs, have declined even faster. Evidence suggests that modern inactive lifestyles are at least as important as diet in the aetiology of obesity and possibly represent the dominant factor.
The size of the problem
Department of Health statistics show that the prevalence of serious obesity doubled in Britain between 1980 and 1991 (fig 1) and is continuing to increase.4 In the United States, latest survey data show that obesity is much more prevalent than in Britain and is still increasing; in certain ethnic and regional subgroups 50% of women are clinically obese.5 The American experience provides no grounds for optimism regarding the developing epidemic in Britain.
Obesity is one of the most important avoidable risk factors for a number of life threatening diseases and for serious morbidity.6 In the United States it has been estimated to contribute 8% of all illness costs (around £40 billion a year).7 For these reasons the Health of the Nation initiative has recognised obesity as a key target and set …