Experts said analysis of statistics needs to continue to help boost people's health amid concerns at cuts being considered at the Office of National Statistics (ONS).
A public consultation is under way examining how the ONS can save around £9 million this year and next in the face of "significant funding pressures".
Up to £1 million will need to come from reducing a number of its statistical outputs, including those relating to births, deaths, life expectancy and health inequalities.
But Dr John Middleton, vice president for policy at the Faculty of Public Health, said cutting analysis of vital data could lead to a widening gap between the "health haves and health have nots".
His comments came as the ONS released its latest figures showing that the affluent London borough of Richmond upon Thames has the highest healthy life expectancy (HLE) for men and women in England. Men and women in the area have a HLE of 70.3 years and 72.1 years respectively.
The lowest HLE was in Manchester for men at 55 years and Tower Hamlets for women at 54.1 years - a 15-year gap compared to Richmond upon Thames.
Dr Middleton said: "The kind of data that is published today may not be available in years to come. The Office for National Statistics is having to consider cutting programmes that measure this vital information. We need to keep monitoring as much as we can about our health so that we can continue to improve it. Otherwise, the gaps between the 'health haves' and 'health have nots' will continue to get wider."
Around 80% of the ONS' output is required by law. The ONS said in a statement: "The consultation includes a limited number of non-statutory outputs ... only some of which would have to be reduced in order to make the required savings. In many cases alternative statistics on these subjects will continue to be available, although these may be published less frequently or in less detail."
A Department of Health spokesman said: "These figures highlight that we must continue to work to narrow the gap in health inequalities because everyone should have the same opportunity to lead a healthy life, no matter where they live or who they are.
"The Health and Social Care Act sets out the first ever specific legal duties on health inequalities for NHS England, clinical commissioning groups, and for the Secretary of State. Local councils have received ring-fenced budgets to help local people get healthier and to reduce health inequalities."