Meat linked with cancer risk

People who eat a lot of red meat and processed meats have a higher risk of several types of cancer, including lung cancer and colorectal cancer. Researchers defined red meat as all types of beef, pork and lamb. Processed meat included bacon, red meat sausage, poultry sausage, luncheon meats, cold cuts, ham and most types of hot dogs including turkey dogs. Previous studies have also associated meat consumption with cancer risk. Meats can cause cancer by several routes, as they are sources of both saturated fat and iron, which have independently been associated with carcinogenesis. Meat is also a source of several chemicals known to cause DNA mutations, including N-nitroso compounds, heterocyclic amines and polycyclic aromatic hydrocarbons. Researchers at the US National Cancer Institute studied 500,000 people aged 50-71 years who took part in a diet and health study done in conjunction with the AARP, formerly the American Association for Retired Persons. After a follow-up of eight years, 53,396 cases of cancer were diagnosed. Statistically significant elevated risks (ranging from 20 per cent to 60 per cent) were evident for oesophageal, colorectal, liver and lung cancer, comparing individuals in the highest with those in the lowest quintile of red meat intake. The people in the top 20 per cent of eating processed meat had a 20 per cent higher risk of colorectal cancer — mostly rectal cancer — and a 16 per cent higher risk for lung cancer. Furthermore, red meat intake was associated with an elevated risk for cancers of the esophagus and liver. These differences held even when smoking was accounted for. However, red meat intake was not associated with gastric or bladder cancer, leukaemia, lymphoma or melanoma. The findings show that a decrease in the consumption of red and processed meat could reduce the incidence of cancer at multiple sites.