A national survey confirming substantial health inequalities is set to inform ministers' decisions on the location of health action zones.
People living in inner cities and the North suffer poorer health than the rest of the country, according to the 1996 Health Survey for England, published this week.
Geography, wealth and class do make a difference to people's health, the survey indicates.
Those living in deprived urban areas and poor communities in the North are more likely to suffer generally poor health, asthma, obesity and high blood pressure than people from wealthier districts. They are also more likely to smoke.
The findings come as the government prepares to launch the first wave of HAZs to pilot new models of care, and to eradicate health inequalities.
The data will also be used to develop and monitor the forthcoming public health green paper.
Launching the findings this week, chief medical officer Sir Kenneth Calman said the survey would be used to develop policies to enable people to live longer and healthier lives.
Some 9,350 households involving 16,443 adults and 3,885 children took part in the survey. Sixteen per cent of men and 17 per cent of women aged 16-64 were classified as obese, compared with 13 per cent of men and 15 per cent of women in 1991.
The likelihood of obesity is higher in manual than non-manual social classes for both sexes.
Self-reported cigarette smoking prevalence increases progressively from social class I to social class V, the data shows.
Health Survey for England 1996. Available from HMSO. pounds60.