Obesity now causes more cases of four (4) common cancers in the UK than smoking. Cancer Research UK says bowel, kidney, ovarian and liver cancers are more likely to have been caused by being overweight than by smoking tobacco. It says millions are at risk of cancer because of their weight and that obese people outnumber smokers by a ratio of two to one.
While the link between obesity and cancer is well established, the biological mechanisms behind it are not yet fully understood. Fat cells make extra hormones and growth factors that tell cells in the body to divide more often. This increases the chance of cancerous cells being made too.
However, being overweight or obese does not really mean a person will definitely develop cancer but it does raise their risk. And this risk is higher the more weight a person gains and the longer they are overweight for.
According to the UK report, 13 different cancers are linked to obesity and they are: breast (in women after the menopause), bowel, pancreatic, oesophageal (food pipe), liver, kidney, upper stomach, gallbladder, womb, ovarian, thyroid, multiple myeloma (blood cancer) and meningioma (brain cancer).