Men living in the most deprived areas of Croydon die, on average, 10 years younger than those in the most affluent.
A review of health and well-being in Croydon showed the stark contrast across the borough between the have and the have nots.
Men living in Selhurst ward have an average life expectancy of 75, compared with almost 85 years for those in Heathfield Ward.
The worst in the UK is 73.6 in Blackpool, while the unitary authorities of Manchester, Blackburn and Darwen and Salford are the only others lower on average than Selhurst.
The contrast for women is narrower at 5.4 years between the lowest in Fieldway and the highest in Selsdon and Ballards.
George Ayers, a member of the shadow heath and well being board and councillor for New Addington, which has some of the worst areas of deprivation in London, said: “The huge disparity across Croydon is nothing new and these figures show that more needs to be done.
“One area we have been approaching is looking at lifestyle choices, in particular the opening of the Brenda Kirby Cancer Centre.
"Certain types of cancer such as lung cancer, have been linked directly to lifestyle and we have made big strides there.”
Deprivation figures across the borough are split into groupings of 1,500 people, with an area of New Addington within the 1,000 most deprived in Greater London, based on factors such as income, employment, housing, crime and education.
The Joint Strategic Needs Assessment (JSNA) conducted by Croydon Council and South West London NHS, revealed Croydon’s men and women have a higher life expectancy than the England average, and Croydon’s men, at 79.5 is higher than London’s average of 78.6.
The review also revealed there has been an increase in child obesity, homelessness, take up of immunisations as well as the highest repeat abortion rate in the country.
Positives included good rates of breast feeding, numbers quitting smoking and low numbers committing suicide.
Kate Woollcombe, Croydon director of public health, said: “Every decision the council makes has an impact on health and well being positively or negatively that is why the JSNA is integral.”
The figures showed the life expectancy disparity between rich and poor areas is greater in Croydon than both London and England as a whole. In London the lowest life expectancy for men is in Tower Hamlets and Greenwich at 76.7, while men in Kensington and Chelsea live to 85.1.
Coun Margaret Mead, cabinet member for adult services and health said: “Obviously this has been an issue for some time, and it should be noted the gap has narrowed.
“We have always recognised New Addington has always needed more support than some other areas and we have looked to bring in things like the food initiative to encourage better lifestyle.”
Croydon Council will take complete control of public health issues in April next year when primary care trusts are dissolved as part of the Health and Social Care Act.
Coun Mead said: “This latest JSNA indicates the areas we need to focus on. We are working towards next April, when public health will come directly under the council’s responsibility.”