Bodyweight and risk of cancer in the UK - statistics

There is convincing evidence that being overweight or obese increases cancer risk 1. It is estimated that, in the UK, current levels of overweight and obesity could lead to around 19,000 cases of cancer each year. 2. Table 2.1 summarises what we currently know about overweight, obesity and risk of cancer.

Table 2.1: Overweight, obesity and cancer risk - summary

Download this table (20.5KB)

The best evidence for a relationship between cancer and excess bodyweight is for cancers of the endometrium, kidney, oesophagus and gastric cardia (adenocarcinoma), colon, breast cancer in post-menopausal women, gallbladder and pancreas. Figure 2.1 shows the proportions of some of these cancers caused by being overweight or obese. 2,13, 14

Figure 2.1: Proportion of selected cancers caused by overweight and obesity

Download this chart (21KB)

Back to top ^

Obesity (BMI of 30 or above) increases the risk of developing endometrial cancer by two to four-fold and the risk increases linearly with increases in BMI above 25 (overweight) 3. Obesity also increases the risk of breast cancer in post-menopausal women by up to 30%. 4, 5,13By contrast, pre-menopausal women with a BMI of 31 or more have been shown to have a 46% reduced risk of breast cancer, compared with women whose BMI is less than 21. 5 This risk reduction may be because obesity can disrupt ovulation 6.

A likely mechanism for the increased risk for breast and endometrial cancer in overweight women is that fatty tissue alters the levels of sex steroids. In men and post-menopausal women, fatty tissue is a major site for synthesis of oestrogens. Obesity can also increase concentrations of oestradiol in the plasma by reducing levels of sex-hormone binding globulin caused by higher insulin production and insulin-like growth factor I activity. Breast cancer risk is also affected by age at menarche and height, both of which are influenced by bodyweight earlier in life 6.

The risk of colon cancer increases by about 25% in overweight men and by about 50% in obese men compared to men with a BMI under 25. 15. The link between overweight and colon cancer is weaker in women, with a meta-analysis showing a non-significant 9% increase in risk for obese women compared to women with a healthy bodyweight (BMI<25). 15. Central obesity may be a better indicator for colon cancer risk than BMI, with the European Prospective Investigation into Cancer and Nutrition showing similar risk increases in men and women, of up to 50%, for having a higher waist circumference or waist-to-hip ratio. 17 It has been shown that high levels of physical activity can reduce or remove the effect of obesity on the risk of colon cancer 7.

Risk of renal cell cancer increases by 24% in men and 34% in women with a 5-point increase in BMI, risk of oesophageal adenocarcinoma by approximately 50% in men and women and risk of gallbladder cancer by 59% in women, but not in men, for the same increase in BMI. 16.

Two recent large prospective studies in America support an association between obesity and pancreatic cancer, and a meta-analysis showed a 19% risk increase for obese individuals. 9, 10,20. Other cancers that have been linked with BMI in at least one meta-analysis include liver, thyroid, leukaemia, multiple myeloma and ovarian. 13,16,18, 19,21

In England, a total of 66% of men and 57% of women have a BMI of 25 or more: this includes 24% of men and 25% of women who are obese ( Figure 2.2) 12. In addition, 33% of boys and 35% of girls aged 2-15 in England are overweight or obese 11.  

It has been estimated, based on non-linear regression of trends in BMI in England between 1993-2004, that by 2050 60% of males and 50% of females in England will be obese. Based on the same analysis, it has been estimated that, by 2021, the proportion of overweight adult men in England will be equal to the proportion of obese men – around 43% in each group, while the proportion of men with a healthy bodyweight (BMI <25) will be 13%. For women, it has been estimated that the proportion of overweight and obese adults will be equal in 2024 (both 35%), while only a quarter of adult women will have a healthy BMI. 22

Figure 2.2: Bodyweight of British adults, 1993 and 2002

Download this chart (13.5KB)

Back to top ^

 

 

 
Back to Tobacco and cancer risk - statistics Back to
Tobacco and cancer risk - statistics
Forward to Physical activity and risk of cancer - statistics Forward to
Physical activity and risk of cancer - statistics

Browse related content

 

References for bodyweight and cancer risk

  1.  Diet, Nutrition, and the Prevention of Chronic Disease: Report of a joint WHO/FAO expert consultation, in WHO Technical Report Series. 2002, World Health Organisation/Food and Agriculture Organization: Geneva.
  2.  Renehan, A.G., et al., Incident cancer burden attributable to excess body mass index in 30 European countries. Int J Cancer, 2009.126(3): p. 692-702.
  3.  Bianchini, F., R. Kaaks, and H. Vainio, Overweight, obesity, and cancer risk. Lancet Oncol, 2002. 3(9): p. 565-74.
  4.  Lahmann, P.H., et al., Body size and breast cancer risk: Findings from the European prospective investigation into cancer and nutrition (EPIC). Int J Cancer, 2004. 111(5): p. 762-71.
  5.  van den Brandt, P.A., et al., Pooled analysis of prospective cohort studies on height, weight, and breast cancer risk. Am J Epidemiol, 2000. 152(6): p. 514-27.
  6.  Key, T.J., et al., Diet, nutrition and the prevention of cancer. Public Health Nutr, 2004. 7(1A): p. 187-200.
  7.  Murphy, T.K., et al., Body mass index and colon cancer mortality in a large prospective study. Am J Epidemiol, 2000. 152(9): p. 847-54.
  8.  Moore, L.L., et al., BMI and waist circumference as predictors of lifetime colon cancer risk in Framingham Study adults. Int J Obes Relat Metab Disord, 2004. 28(4): p. 559-67.
  9.  Michaud, D.S., et al., Physical activity, obesity, height, and the risk of pancreatic cancer. JAMA, 2001. 286(8): p. 921-9.
  10.  Patel, A.V., et al., Obesity, recreational physical activity, and risk of pancreatic cancer in a large U.S. Cohort. Cancer Epidemiol Biomarkers Prev, 2005. 14(2): p. 459-66.
  11.  Health Survey for England 2004: Updating of trend tables to include childhood obesity data. [Summary of key findings] The NHS Information Centre for Health and Social Care 2006
  12.  Health Survey for England - 2008 trend tables. The NHS Information Centre for Health and Social Care 2009.
  13.  Reeves, G.K., et al., Cancer incidence and mortality in relation to body mass index in the Million Women Study: cohort study. BMJ, 2007. 335(7630): p. 1134.
  14.  Merry, A.H., et al., Body mass index, height and risk of adenocarcinoma of the oesophagus and gastric cardia: a prospective cohort study. Gut, 2007. 56(11): p. 1503-11.
  15.  Moghaddam, A.A., et al., Obesity and Risk of Colorectal Cancer: A Meta-analysis of 31 Studies with 70,000 Events. Cancer Epidemiol Biomarkers Prev, 2007. 16(12): p. 2533-47.
  16.  Renehan, A.G., et al., Body-mass index and incidence of cancer: a systematic review and meta-analysis of prospective observational studies. Lancet, 2008. 371: p. 569-78.
  17.  Pischon, T., et al., Body size and risk of colon and rectal cancer in the European Prospective Investigation Into Cancer and Nutrition (EPIC).J Natl Cancer Inst, 2006. 98(13): p. 920-31.
  18.  Larsson, S.C. and Wolk, A., Overweight, obesity and risk of liver cancer: a meta-analysis of cohort studies.Br J Cancer, 2007. 97(7): p. 1005-8.
  19.  Schouten, L.J., et al., Height, body mass index, and ovarian cancer: a pooled analysis of 12 cohort studies.Cancer Epidemiol Biomarkers Prev, 2008. 17(4): p. 902-12.
  20.  Berrington de Gonzalez, A., et al., A meta-analysis of obesity and the risk of pancreatic cancer. Br J Cancer, 2003. 89(3): p. 519-23.
  21.  Leitzmann, M.F., et al., Body mass index and risk of ovarian cancer. Cancer, 2009. 115: p. 812-22.
  22.  McPherson, K., Marsh, T. and Brown, M. Tackling obesities: Future choices -- Modelling future trends in obesity and the impact on health 2nd Edition. 2007.