The World Health Organisation's report on health inequalities is a stark reminder that tackling the growing gap between rich and poor is not only a moral imperative, but an economic one.
The report concludes a "toxic combination of bad policies, economics and politics is in large measure responsible for the fact that a majority of people in the world do not enjoy the good health that is biologically possible. Social injustice is killing on a grand scale."
It found that in the UK, a boy from St Pancras could expect to die 11 years earlier than one from Hampstead, just a few underground stops further north and that in Calton, a suburb of Glasgow, children's life expectancy is 28 years less than in nearby Lenzie. At 63, people from India can expect to live a decade longer than those from Calton.
Discrepancies in life expectancy within the UK are not new. Those from affluent areas tend to enjoy longer, healthier lives than those from more deprived neighbourhoods. But that does not make it any the less shocking that some parts of the UK have lower life expectancies than developing countries or that a matter of a few miles can make such a big difference to how long you can expect to live.
While governments of any political persuasion are in a position to do something about many of the causes of poor health – the report concludes education and bad housing need particular attention – tackling others require citizens to change their lifestyle. That will be easier said than done. But failure could prove costly.
Take obesity. Poor diet can lead to poor health. If trends continue, a quarter of children and the majority of the adult population will be obese by 2050, according to a report by the government's Foresight committee. It estimates that related consequences such as soaring diabetes, heart disease and strokes will cost the NHS £6.5bn alone, while additional impacts, such as a high proportion of the population unable to work, will take the total bill to £49bn.
It is not simply a question of getting children, and their parents, to eat less. Compared to the late 1970s, seven- to 12-year-olds are consuming fewer calories, not more. It's about getting them to be more active.
Whether the Tories' "nudge" policies or Labour's obesity strategy, it is hard to see how policies dreamt up in the Westminster village can engineer the sort of behaviour change required to halt, let alone reverse the inexorable rise of children and adults who are clinically obese.
The government is to be lauded for trying to tackle the issue head on, but to date its efforts have largely been in vain. The target, set in 2004, "to halt by 2010 the year on year increase in obesity among children under 11" has proved too ambitious, despite measures including a national weighing programme for four- and 10-year-olds, traffic light food labeling, the five-a-day fruit and vegetable campaign and banning junk food advertising during programmes aimed at the under 15s.
The Tories' policies promise more of the same: more visible food labeling, reduction of portion sizes and "proportionate" regulation on advertising.
Even though the five-a-day campaign has been running since 2003, only 17% of children actually eat at least five portions a day. And the latest target seems to be going backwards. Rather than halt the rise in child obesity by 2010, the new target just aims to reduce it by 2020.
The culture and children's departments want all children doing five hours of school sport a week by 2010 while a new play strategy will make it easier to encourage children who don't like sport to be active.
But the WHO suggests that to really achieve health inequalities, all policies must be checked for the extent to which they promote healthy equity. Too often, they hamper not promote healthy living.
"Trade policy that actively encourages the unfettered production, trade, and consumption of foods high in fats and sugars to the detriment of fruit and vegetable production is contradictory to health policy," the report notes.
To test trade policy against health goals in this way would involve a level of intervention and regulation of the economy that – excuse the pun – the government would find too hard to swallow.
Perhaps the answer is not top-down direction from the government, but a tougher attitude to obesity locally. The Local Government Association thinks we need to be even tougher. Shouldn't children who are morbidly obese be placed on the "at risk" register, it argues, on the grounds that their health is threatened just as much as if they were malnourished? It seems drastic, but council leaders may have a point.