Overweight and obesity is linked to a range of health conditions, including at least 13 types of cancer. UK overweight and obesity prevalence is among the highest in Europe, and has increased markedly in recent decades.
This study estimated future levels of adult overweight and obesity across the UK, up to 2040. It used BMI data from national health surveys and trends to project future prevalence. The analysis examined patterns for the UK overall and for each UK nation, as well as differences by sex and socioeconomic deprivation.
The aim was to understand how prevalence of overweight and obesity may develop in the coming decades and which population groups are likely to be most affected.
If current trends continue, average adult overweight and obesity prevalence is projected to continue increasing across the UK through to 2040. By 2040, 71% of UK adults are projected to be either overweight or living with obesity, compared to 64% in 2019.
The increase is expected to be driven by increases in obesity (including severe obesity). If current trends continue, average adult severe obesity prevalence in the UK is projected to almost double from 3% in 2019 to 6% by 2040 (91% relative increase).
The proportion of adults at a healthy weight is expected to decline, and if current adult BMI trends continue, it is projected that there will be more people who are obese compared to people who are healthy weight in the UK by 2040 – making obesity the most common BMI status.
If current obesity prevalence trends continue, the deprivation gap for obesity between the least and most deprived groups is projected to increase by more than half in England and Scotland by 2040.
These findings suggest that overweight and obesity will remain a major public health challenge in the UK over the coming decades. Projected growth in the proportion of people towards the highest end of the BMI scale is concerning because poorer health outcomes, including risk of several types of cancer, are often associated with higher BMI. As overweight and obesity become more common across the population, the number of people living with obesity-related illness is also likely to rise, increasing pressure on health services and wider society.
The persistence of inequalities is also important: obesity is projected to remain more common in areas of higher socioeconomic deprivation, potentially widening existing health inequalities.
These findings highlight the need for population-wide approaches that make healthy diets and physical activity easier and more accessible, alongside targeted action to support groups at greatest risk. Future research should continue monitoring trends, evaluate the impact of obesity prevention and treatment policies, and explore how changing patterns of obesity may influence future disease burdens, including cancer.
Read the report in fullNick Payne, Katrina Brown, Amar Ahmad, Christine Delon & Sam Finnegan.
