The Role of Nutrition in Cancer Prevention

food spread out on table
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A hundred years ago, cancer was such a scary subject that nobody talked about it. These days we talk about it more. We also get sick and die of it more. In 1900, one out of every 33 people died of cancer. Today, cancer kills more than one in four Americans. 

Why is this happening? High body fat and inactivity contribute to this. Another contributing factor is the way we eat. In fact, 25%-35% of cancers are due to diet.

 The nutrients we take in directly affect the mechanisms that make cancer grow and spread. And indirectly, they can help to manage the biochemical conditions that encourage or discourage the disease.

The good news? By eating better, you can lower your risk. 

Meat and Cancer

Cancer rates (and types) vary considerably around the world, but one thing is clear: the countries that eat the most meat also have the highest rates of cancer.  

Does that mean that eating meat causes cancer? Not necessarily. The problem may be the type of meat, or that maybe meat eaters may also eat more processed foods, or fewer vegetables. Studies are ongoing to help determine what’s going on, but in the meantime, it’s best to moderate your consumption of processed meat.

Indeed, processed meats pose the biggest risk. For example, eating just two ounces of processed meat a day can increase your risk of colorectal cancer by 21%.

Plants and Cancer

People who eat large amounts of fruits and vegetables are half as likely to develop cancer as people who don’t. You read that right. Eating plenty of plant foods can cut your cancer risk in half.

But not all plant foods help. Highly processed plant foods (like potato chips) won’t protect you from cancers and might contribute to them.


What to Do Now

Now you know that eating too much processed meat seems to make cancers worse and eating lots of plant foods seems to cut the risk, but what else can you do to protect yourself from developing diet-related cancers?

Here are ten tips to make your table healthier.

  • Stay lean: Some of the strongest evidence available links excess body fat with cancer. Up to one third of colon, breast, kidney, and digestive tract cancers are associated with being overfat.

  • Eat healthy fats: Balance dietary fat by choosing more unsaturated and omega-3 rich foods (flax, hemp, fish, walnuts, avocado, etc.).

  • Limit sugars: Cut back on added sugars and refined carbohydrates.

  • Limit processed animal products: Cut back on processed meats.

  • Eat lots of plant foods: Especially beans, vegetables, fruits, and whole grains. 

  • Drink water and tea.

  • Limit alcohol.

  • Don’t take unnecessary supplements.

And, while not specifically diet-related, these are too important to leave out:

  • Exercise regularly: Five hours or so a week seems to be the sweet spot.

  • Don’t smoke.

By following these recommendations, you can cut your risk of cancer by up to 60%. Don’t become another negative statistic. Start by making one small change and building from there.


Alexander DD, et al. Meta-analysis of animal fat or animal protein intake and colorectal cancer. Am J Clin Nutr 2009;March 4th Epub.

Byers T.  Nutrition and lung cancer: lessons from the differing effects of foods and supplements.  Am J Respir Crit Care Med 2008;177:470-471.

Chlebowski R. Low-fat diet may reduce risk of breast cancer relapse. American Society of Clinical Oncology annual meeting: Summary of clinical trial results.  Accessed April 30, 2009.

Cho E, et al. Premenopausal fat intake and risk of breast cancer. J Natl Cancer Inst 2003;95:1079-1085.

Cross AJ, et al. A prospective study of red and processed meat intake in relation to cancer risk. PLoS Med 2007;4: e325.

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