Cancer is a complex illness caused by numerous factors. Some, like those related to genetics, are out of your control but many, such as smoking and physical activity, are cancer risk factors you can drastically influence.
Your diet is one such factor that you can tweak to help lessen your risk of developing cancer down the line. In fact, of the nearly 569,500 cancer deaths that occurred in 2010, it’s estimated that one-third were related to physical inactivity, poor nutrition, obesity or being overweight (also often diet related), and therefore could have been prevented.1
You’ve probably already heard the advice to eat lots of fruits and vegetables, or at least five servings a day, to help fight chronic illnesses like cancer. But, just as important as knowing which foods to eat to help prevent cancer is knowing which foods to avoid.
The Top Cancer-Causing Foods to Avoid
In order to use your diet as a strategic “weapon” against cancer, one of the easiest things you can do is make sure the following foods are not a part of your regular diet.
1. Processed Meats
You may love hot dogs, lunch meat, bacon and sausages, but these meats are among the worst of the worst for your health. When you eat processed meats, you’re almost assuredly consuming sodium nitrite (or sodium nitrate), which is added to processed and cured meats as a preservative, flavoring, color fixative and antimicrobial agent.
Unfortunately, nitrites can be converted into cancer-causing nitrosamines in your body, which may explain why numerous studies have linked processed meat consumption to cancer. For instance:
- People who eat a lot of processed meat may be 50 percent more likely to develop colorectal cancer than those who eat the least.2
- Increased consumption of processed meat is associated with an increased risk of stomach cancer.3
- Eating a lot of processed meat is linked to a 68 percent higher risk of pancreatic cancer compared to eating only a small amount.4
2. Red Meat
While some red meat can safely be included in your diet (for instance, grass-fed beef, which contains conjugated linoleic acid (CLA) that may help to fight cancer)5, there is evidence that eating a lot of red meat can increase your cancer risk. One such study found that eating red meat daily for 10 years (in an amount equivalent to a quarter-pound hamburger) increased men’s risk of dying from cancer by 22 percent, and women’s by 20 percent.6
Separate research has also linked red meat consumption to an increased risk of breast,7 colon and prostate cancers.
3. Charred and Well-Done Meats
The way you cook your meat may actually make a big difference in the cancer risk it poses to you, with well-done and char-grilled meats among the worst offenders.
Many studies have shown a correlation between eating well-done meat cooked at high temperatures and an increased risk of cancer, and at least part of that risk is likely due to toxic cooking byproducts.
For instance, when amino acids and creatine (a chemical found in muscle meats, including beef, pork, chicken and fish) interact with high cooking temperatures, heterocyclic amines (HCAs) are formed. At least 17 different HCAs have been identified that may increase cancer risk,8 including colon cancer, stomach cancer and others.
Further, a review of 30 epidemiological studies found that 80 percent showed a link between eating well-done meat and cancer.9 A separate study also found a link between charred meat and pancreatic cancer, with those eating the most very well done meat at a 70 percent increased risk compared to those who ate the least.10
4. French Fries and Potato Chips
Potato chips and other snack chips and French fries may contain high levels of acrylamide, another carcinogenic substance that forms when foods are heated at high temperatures, such as during baking or frying.
Animal studies have shown the substance increases the risk of several different types of cancer, and the International Agency for Research on Cancer states that acrylamide is a “probable human carcinogen.”
Generally speaking, acrylamide may be found in any food heated to a temperature above 248 degrees Fahrenheit, but potato chips and French fries have been found to contain the highest levels among foods tested.11
According to the National Cancer Institute:12
“The World Health Organization (WHO) and the Food and Agriculture Organization (FAO) stated that the levels of acrylamide in foods pose a “major concern” and that more research is needed to determine the risk of dietary acrylamide exposure.”
5. Sugar — Especially Fructose
You may have heard the notion that sugar feeds cancer cells, and although all cells, even healthy cells, use glucose to grow, cancer cells use sugar more efficiently, and in greater quantities, than healthy cells. Research shows a strong connection between sugar consumption and cancer, so much so that you may want to limit or at least moderate your intake to reduce your cancer risk. For instance:
- Women who ate the most high-glycemic-load foods were close to three times more likely to develop colorectal cancer.13
- High blood sugar levels, caused by health conditions like diabetes along with eating too many sugary foods, have been linked to cancers of the pancreas, skin, uterus, urinary tract and breast. Further, women with the highest blood sugar levels were found to have a 26 percent higher risk of developing cancer than those with the lowest.14
- Women with the highest carbohydrate intake (62 percent of their diet or more) were more than twice as likely to develop breast cancer than those with a lower carb intake (52 percent or less).15
One recent study also found that fructose — found in soda and many other processed sweets — may feed cancer cells even more than glucose.16
The researchers “fed” both glucose and fructose to pancreatic cancer cells in lab dishes and found that although the cells thrived on glucose, they used fructose to divide and increase proliferation. The researchers even suggested that limiting the intake of refined fructose may disrupt cancer growth.17
Cancer is currently the second most common cause of death in the United States (heart disease is first), accounting for nearly one of every four deaths.18 While it may be impossible to eliminate your risk entirely, cutting back on, or eliminating, these cancer-causing foods from your diet is one simple way to stay healthy and help keep your cancer risk as low as possible.
Again, eliminating cancer-causing foods is only one way to use your diet to lower your cancer risk. Stay tuned for an upcoming newsletter on the best foods to eat more of to help keep cancer away.
1. American Cancer Society Facts & Figures 2010
2. JAMA. 2005 Jan 12;293(2):172-82.
3. J Natl Cancer Inst. 2006 Aug 2;98(15):1078-87.
4. J Natl Cancer Inst. 2005 Oct 5;97(19):1458-65.
5. Cornell University Department of Animal Science, The Bauman Research Group, Conjugated Linoleic Acid (CLA) Studies.
6. Arch Intern Med. 2009;169(6):562-571.
7. Arch Intern Med. 2006;166:2253-2259.
8. National Cancer Institute, “Heterocyclic Amines in Cooked Meats” September 15, 2004.
9. Nutrition Reviews 2005 May;63(5):158-65.
10. ScienceDaily.com April 22, 2009.
11. Food and Agriculture Organization of the United Nations. World Health Organization. Summary report of the 64th meeting of the Joint FAO/WHO Expert Committee on Food Additives (JECFA), February 8-17, 2005.
12. National Cancer Institute “Acrylamide in Food and Cancer Risk.”
13. Journal of the National Cancer Institute February 4, 2004;96(3):229-233.
14. Diabetes Care, Vol. 30, No. 3, March 2007: 561-567.
15. Cancer Epidemiology Biomarkers & Prevention August 2004;Vol. 13, 1283-1289.
16. Cancer Research August 1, 2010; 70: 6368.
17. Reuters.com August 2, 2010.
18. American Cancer Society Facts & Figures 2010.