A look at the underlying factors that could explain socio-economic inequalities in obesity.
Obesity rates have risen to epidemic proportions and it is now one of the western world's most serious health problems. But why does it appear to affect poor people most?
The World Health Organisation estimates that in 2005 about 1.6 billion adults worldwide were overweight, of whom at least 400 million were obese. People who are overweight or obese have a higher risk of heart disease, Type II diabetes and other diseases including some cancers.
The spread of obesity among children is also alarming experts. At least 20 million children under the age of 5 years were overweight in 2005, according to the WHO. In Britain, it is predicted that by 2050, 60 per cent of today's children will be overweight or obese adults — costing taxpayers an estimated £50 billion.
Despite the enormity of the problem, it is still not clear why the poorer people are, the more likely they are to become obese. A better understanding of the socio-economic forces that lie behind the increase in obesity is vital for implementing health and food policies to control its emergence and reduce the effects on health and well being.
The LSE's Joan Costa-i-Font and the University of Barcelona's Joan Gil analysed obesity patterns in Spain where half of the population is overweight and 14.5 per cent obese. After the UK, Spain is the EU country with the highest increases in obesity rates over the last decade. Given the association between chronic diseases such as heart disease and obesity, it is responsible for 18,000 or 5.5 per cent of deaths a year in Spain. It is thought to be responsible for as much as seven per cent of total health expenditure.
Dr Costa-i-Font, a Senior Research Fellow in Health Economics at LSE Health, and Dr Gil found that roughly 70 per cent of inequalities in obesity are explained by differences in education rather than low income alone. Lack of education usually leads to low income which explains why there are income-related inequalities in patterns of obesity.
Dr Costa-i-Font says: "We found that roughly 50 per cent of the inequalities in obesity are explained by differences in education and that its effect is even more important than that of income alone."
He argues that government policy should concentrate on changing behaviour by educating people about the health risks associated with obesity and about the importance of eating healthily and exercising. This would prove more effective, he says, than efforts to boost the incomes of poor people or to tax fat content in food. Although some research finds that obesity is linked to cheaper foods, other evidence questions the possible effects of the introduction of 'fat taxes' on products with high fat content.
Dr Costa-i-Font concludes: 'The introduction of "fat taxes" would be regressive and expand income inequalities even more. However, promoting or subsidising education about healthy lifestyles may well change behaviour of certain low-income groups currently more orientated to the consumption of junk food.'
What lies behind socio-economic inequalities in obesity in Spain? A decomposition approach by Dr Joan Costa-i-Font and Dr Joan Gil is published in the journal Food Policy.
For more details about Dr Costa-i-Font and his research, see his entry in LSE's Experts Directory: Dr Joan Costa-i-Font