Diet and Cancer Risk
While no one food or lifestyle can prevent cancer, healthy food choices may help to lower your risk. Studies have looked at what we eat, but they have not been able to prove that certain foods can lower your risk. Experts say that a diet high in fruits and vegetables "probably" lowers cancer risk, but we don't know for sure.
What we do know is that a healthy diet, along with regular physical activity and maintaining a healthy weight has been shown to lower cancer risk. These three things together are known as the “cancer prevention triangle”. Together, they are thought to be the second most important step, after not smoking, in preventing cancer.
Foods Linked to a Possible Increased Cancer Risk
There are certain foods that have been linked to a possible increase in cancer risk:
Red Meat
A diet high in red meat (beef, pork, and lamb) is thought to increase your risk for colon and rectal cancers. There may be a link between red meat and pancreatic cancers, but studies have found mixed results. It is likely that eating red meat in moderation does not increase the risk of cancer. The AICR (American Institute for Cancer Research) suggests that people eat no more than 18 ounces (cooked weight) of red meats per week to reduce cancer risk.
Processed & Fermented or Cured Meats
Processed (hot dogs, bologna, and lunchmeat) and cured or fermented meats (sausage, salami) eaten regularly increases the risk of colon, rectal, and gastric cancers. There may also be a link to endometrial and pancreatic cancers. These foods, as a result of how they are prepared, have nitrosamines, nitrate, and N-nitroso-compounds (NOCs), which have been shown to cause cancer.
Salted and Pickled Foods
Foods preserved by salting, pickling, or smoking are linked to increased rates of stomach (gastric) cancers. This may be because of the presence of nitrates, high amounts of salt, and possible contamination with the bacteria H. Pylori. Foods like meat, fish, and vegetables, that are preserved with salt, can damage the lining of the stomach. They can also contain nitrates that can lead to cancer. H. Pylori is a bacteria that can be found in some foods. It damages the stomach lining and can cause stomach cancer. It is thought that it grows quickly when a person eats a lot of salt – like in salted, pickled, and smoked foods. People whose diets regularly include pickled foods have been found to have higher rates of stomach cancer.
Charred Meats
There are compounds that form as a result of cooking meats at high temperatures (pan-frying or grilling). These compounds include Heterocyclic Amines (HCAs) and Polycyclic Aromatic Hydrocarbons (PAHs). Studies have found that eating lots of charred (or burned) meat may increase the risk of developing colon, rectal, pancreatic, and prostate cancers.
White Breads, Rice, and Processed Grains
Eating white bread, white rice, and processed grains may increase your risk for colon, rectal, and endometrial cancers because of their link to obesity. Try replacing these foods in your diet with whole grains and brown rice. Many studies have tried to link a diet high in whole grains to reduced cancer risk, but these have not always shown a benefit. The strongest link seen in these studies was that a diet high in fiber and whole-grain foods may lower colon cancer risk.
Additional Resources
The three components of the "cancer prevention triangle" (diet, physical activity, weight) are strongly interrelated and working to improve one can often lead to improvements in another. Use the links below to learn more about ways to work towards a healthier you.
- Information on how to Eat Healthy and Get Active at the American Cancer Society website.
- Resources to help Reduce Your Cancer Risk at the American Institute for Cancer Research.
- The American Cancer Society’s Guidelines on Nutrition and Physical Activity for Cancer Prevention.
- WCRF/AICR Continuous Update Project: a project that looks at research on how diet, nutrition, and physical activity affect cancer risk and survival.
- The US Department of Health & Human Services Physical Activity Guidelines for Americans.NIH AARP Diet & Health Study: a study developed at the National Cancer Institute of the National Institutes of Health to improve our understanding of the relationship between diet and health.
- The European Prospective Investigation into Cancer & Nutrition (EPIC): A large study by the International Agency for Research on Cancer investigating the relationships between diet, nutritional status, lifestyle and environmental factors and the incidence of cancer and other chronic diseases.