Increased risk of several cancers
The risk of several cancers is higher in obese people, including endometrial, breast and colon cancers. BMI is associated with cancer risk, with substantial population-level effects (although the heterogeneity in the effects suggests that different mechanisms are associated with different cancer sites and different patient subgroups).
- The International Agency for Research on Cancer (IARC) has found that around 7,000 male and 13,000 female cancer cases in the UK each year could be attributed to obesity –and that over four in 10 cancers in the UK could be prevented through lifestyle changes that encourage healthy eating and exercise. [5]
- Research has suggested that body-mass index (BMI) is an important predictor of cancer risk, 2 and a Norwegian cohort study reported associations with several cancer sites, including the thyroid 3 and ovaries; 4 and the UK Million Women Study showed associations between BMI and ten of 17 sites investigated.5
- Two large reviews brought these and many smaller studies together.6, 7 In a meta-analysis of 221 datasets, strong associations were recorded between BMI and cancers of the oesophagus, thyroid, colon, kidneys, endometrium, and gallbladder, and weaker associations were shown for several other sites. 7
- Increased BMI was negatively associated with lung cancer.