The study found that unhealthy diet accounts for 10.8% of the overall disease burden, whilst tobacco accounts for 10.7%. The disease burden is the years of life lost to death and lived with disability.
Potentially preventable risk factors such as poor diet, obesity, alcohol and smoking explain 40% of ill health in England.
Life expectancy in England increased by 5.4 years between 1990 and 2013, from 75.9 years in 1990 to 81.3 years in 2013, one of the biggest increases compared with the other EU15+ countries (the first 15 countries to join the EU, and Australia, Canada, Norway and the US).
The increase has been factored to falls in the death rate from cardiovascular disease, stroke, chronic obstructive pulmonary disease and some cancers (with progress partly offset by increased death rates from liver disease).
However, improvements in life expectancy haven’t been matched by improvements in levels of ill health.
Britons are living longer but spending more years in ill-health, often with a combination of conditions, some of which would have previously been fatal. For example, with diabetes, the years of life lost to the disease have decreased by 56% but years living with disability have increased by over 75%.
Professor John Newton, chief knowledge officer at Public Health England, said: “The findings show the huge opportunity for preventive public health. If levels of health in the worst performing regions in England matched the best performing ones, England would have one of the lowest burdens of disease of any developed country.
“And even though there have been big falls in premature mortality, the top causes of early deaths in England and in each English region are still heart disease, stroke, lung cancer and chronic obstructive pulmonary disease, which to a greater or lesser extent, are attributable to preventable risk factors.”
Dr Adam Briggs, co-author and Wellcome Trust Research Training Fellow, University of Oxford, said: “Life expectancy is increasing across the country but large inequalities still remain. Life expectancy in 2013 for those living in the most deprived areas was still lower than those in less deprived areas enjoyed in 1990. How deprived you are is the key driver of these differences rather than where you live and therefore deprivation and its causes need to be tackled wherever they occur.”
Professor Kevin Fenton, Director of Health and Wellbeing, Public Health England, said: “People are living longer, but they are living longer with disability, which will require more integrated models of care spanning health and social services.
"The other important implication for health services is that it is likely that up to 40% of its workload is due to potentially preventable risk factors. This reaffirms the importance of people taking positive steps today, liking eating well and stopping smoking, to improve their health in the long term.”
The study was commissioned by Public Health England and published in The Lancet. The full report can be read here.