Poor diet, nutrition and obesity
A diet low in vitamins A and B can raise a person’s risk of head and neck cancer. Eating a lot of salt, cured fish and meat has been shown to increase the risk of throat cancer.
8% of Thyroid cancer cases in the UK are caused by being overweight or obese. The risk is 23% higher per 5-unit BMI increase. CRUK estimates that being overweight is now responsible for at least 1 in 20 cancers, and plays a significant role in a number of different types, including cancers of the bowel, breast, ovary and pancreas. The strength of the link varies but, in general, the heavier you are, the greater the risk, with an obese woman being at least twice as likely to develop womb cancer than a slim peer, and 30 per cent more likely to get bowel cancer.
The mechanism behind the link with weight is complex but excess fatty tissue can encourage metabolic and hormonal changes that promote cancerous change and growth, and impair the ability of the immune system to spot and destroy cancer cells before they become established. Not all fat is equal in this regard. While peripheral fat stores, such as those under the skin and around the buttocks and hips, can affect hormone levels, the most dangerous type is “visceral” fat stored around your midriff (and organs). It is apple-shaped men and women, rather than pears, who are most likely to develop obesity-related cancers.