Londoners may find it difficult to believe that they are uniquely blessed in their home city. As they struggle to work on packed commuter trains, choke on the fumes of juggernauts thundering by inches from the pavement and struggle with their consciences as yet another Big Issue vendor hoves into sight, they might be forgiven for wondering at the effect it all has on their health.

But early research by the Health of Londoners Project suggests it may not be as bad as it appears (see news focus, page 16). Despite London's tremendous size and massive social problems, the raw data seems to show that Londoners' health compares well in many respects with that of people living in other European capitals.

But it is not all good news. Deaths from ischaemic heart disease and respiratory disease are unacceptably high. Teenage pregnancies and abortions are exceptionally high, infant mortality rates are well above average despite a steep decline in the past two decades, too many babies have low birth rates, and far too many adults are obese.

Some of this can be explained away as the product of different data collection and by other factors. But it is clear that the first mayor of London will have to get to grips with the public health challenge facing the capital as a priority. So far, despite interfering in NHS issues where they have no authority, none of the front-runners has done that in any coherent way.