5 Dietary Habits That Could Reduce Your Cancer Risk

January 31, 2023

Learn about the five most impactful dietary changes you can make to help your body prevent or fight cancer.

Every year, many of us make New Year’s resolutions to eat healthier.

But it can be tough to maintain your motivation, especially if you’re sacrificing foods you love for foods that—well, you don’t. 

That, plus my commitment to the Health At Every Size principles, is always on my mind when making dietary recommendations for my patients. AND, at the same time, what you put on your plate and what you drink throughout the day could have a direct impact on your risk for developing cancer. So it’s a fine balance we have to strike. 🙂 

Cancer is the second leading cause of death in the United States, accounting for 1 in 4 deaths, and poor dietary habits have long been recognized to increase cancer risk. Obesity has been recognized as a risk factor for thirteen types of cancer, including gastrointestinal cancers, postmenopausal breast cancer, and prostate cancer. Diet, obesity, and metabolic syndrome may account for as much as 30-35% of cancer deaths, which means that many of those deaths may have been prevented by dietary changes.*

*A quick pause here to acknowledge the anti-fat sentiment that’s been overwhelmingly present in most fields of medicine, dating back hundreds of years, which has caused immeasurable harm to people who live in larger bodies. I try to follow the science, and balancing that against longtime biases in our field is always a tricky gambit. 


Unfortunately, there is no one diet that can guarantee that you won’t get cancer, just like there isn’t a diet that can fight cancer naturally by itself.

However, research has provided much in the way of actionable scientific data on foods that can make a big difference in our health, and that do seem to have anti-cancer effects. 

There are also several metabolic processes in the body that are affected by the foods we eat, many of which are involved in the development of cancer. Inflammation, the way we metabolize hormones, how high our insulin levels are, the health of our gut microbiome, how well our immune system functions—all of these systems can potentially impact your cancer risk factors. 

“Every bite of food you eat broadcast’s a set of coded instructions to your body – instructions that can either create health or disease.” —Mark Hyman, MD

So how can we best eat to create the “coded instructions” to optimize health and prevent cancer?

1. Eat a diet that is “Plant Forward.”

“Plant-forward” is a diet that focuses on fruits and vegetables, legumes, nuts and seeds, but is not limited to those foods.

A plant-forward diet can reduce cancer risk overall. Plants provide us with important vitamins, minerals, phytochemicals and antioxidants as well as fiber that give those coded instructions to our genes to create optimal health. 

Women who eat a high amount of fruits and vegetables each day may have a lower risk of breast cancer, particularly more aggressive types of tumors, according to a study published in the International Journal of Cancer.

  • Lots of cruciferous vegetables. Research has shown evidence that a diet high in cruciferous vegetables, like broccoli, cauliflower, cabbage, kale, brussels sprouts and bok choy may be associated with a reduced risk for both breast and prostate cancers. This is due to compounds in those vegetables, such as sulforaphane, that can change gene expression and help our bodies metabolize our hormones more effectively. 
  • Aim for 5-9 servings of fruits and vegetables per day. An easy way to do this is to have fruits and vegetables make up half of your plate for each meal. 
  • Make organic choices whenever possible. Use the Environmental Working Group’s “Clean Fifteen” and “Dirty Dozen” to identify what which foods you should prioritize buying organic vs. which ones are safe to buy conventional.

2. Focus on fiber.

Fiber rich foods are an important component of an anti-cancer diet. Fiber has many health benefits, including controlling blood sugar and decreasing estrogen levels, which has been shown to help prevent breast cancer. 

Fiber also helps eliminate cancer-causing chemicals in the intestines, which may help lower colon cancer risk. 

Finally, fiber is essential for maintaining a healthy gut microbiome (the trillions of microbes, including bacteria and fungi which live in our gut) which play a role in our immune function as well as likely play a role in cancer risk. 

High fiber foods include beans and lentils, edamame, as well as fruits and vegetables, especially broccoli, berries, avocados, apples, pears, flax and chia seeds. 

If you eat grains, whole grains can also be a source of fiber.

3. Whole foods are best.

  • Being plant-forward also emphasizes whole foods 
  • Eat foods that are as close to how they grew or were produced in nature. This means limiting or eliminating ultra-processed foods (foods with long ingredient lists, including additives, preservatives, food dyes and artificial ingredients).  
  • Include unprocessed foods such as fresh fruits and vegetables, nuts, seeds, legumes, as well as fish and meats.
  • Avoid or limit refined grains, sugar, and highly processed seed oils (canola, vegetable, soybean, safflower, sunflower oil)

4. Be mindful about your protein.

The World Health organization has classified processed meats, including ham, bacon, salami, sausages, and hot dogs as Group 1 carcinogens (known to cause cancer). The nitrite and nitrate preservatives used to cure processed meats are likely the culprit, and can lead to colorectal and stomach cancers. 

The majority of the research points to a diet high in red meat (including beef, lamb, and pork) as being a possible cause of cancer.  However, we know that moderate amounts of red meat provide a good source of protein, iron, zinc and B12. 

There is controversy over whether some of the compounds in red meat itself, or the way in which it is cooked (the black char on grilled meat), present the highest risk. 

  • It is probably not necessary to completely avoid red meat if you enjoy it in your diet. The American Institute for Cancer Research recommends limiting weekly amounts of red meat to 12-18 ounces or less. 

  • Try to find grass fed and grass-finished red meat; it has the highest omega-3 content and the least amount of harmful compounds. Wild caught seafood, organic or at least antibiotic-free poultry, and pastured organic eggs are also good protein sources. 

  • If you consume dairy, choose fermented products such as Greek yogurt, kefir, and cottage cheese that have live cultures, which can also support your gut microbiome.

5. Think before you drink.

  • Hydration is so important for our body to function optimally. Drink filtered water, and ideally not too much out of plastic bottles, as they may contain chemicals like BPA. 

  • If you drink coffee, recent studies have shown a protective effect for head and neck, colorectal, breast, and liver cancer. (I know, I’m psyched about this too.) Hundreds of biologically active compounds including caffeine, flavonoids, lignans, and other polyphenols are found in coffee. These and other coffee compounds have been shown to increase energy expenditure, inhibit cellular damage, regulate genes involved in DNA repair, have anti-inflammatory properties and/or inhibit metastasis, among other activities. 

  • But wait! There is also evidence that coffee consumption is associated with lower risk of insulin resistance and type 2 diabetes, which have been linked to higher risks of colorectal, liver, breast and endometrial cancer incidence and/or death. Just don’t add sugar or artificial sweeteners to your coffee, or creamers with artificial ingredients. 

  • Herbal, green, and black teas also have anti-cancer benefits. 

  • Stay away from soda, both sugar and artificially sweetened, as it has been shown to increase obesity as well as risk for pancreatic, colon, and endometrial cancers. 

  • We now know that as far as cancer risk, there is no “safe” amount of alcohol. Alcohol has been shown to increase risk of cancers of the mouth, throat, larynx, esophagus, liver, colon, rectum and breast. There are many mechanisms at play, including the fact that alcohol is converted into acetaldehyde, a chemical that can damage DNA, as well as  increase reactive oxygen species (free radicals), and increase inflammation. 

  • Alcohol increases risk of breast cancer as it can raise estrogen levels. 

  • If you do drink, limit the amount of alcohol you drink, as well as how often you drink it.

If you already have cancer, it is very important to talk with an experienced professional about the best nutrition advice customized to your type of cancer, your phase of treatment, as well as your overall health concerns and needs. The right anti-cancer diet for someone with breast cancer, for example, may be different from the best diet for someone with prostate cancer, and it will change depending on what phase of treatment you are in.

If you would like specific recommendations on the right anti-cancer diet for you and your individual needs, we would love to work with you. 

If you or a loved one has a cancer diagnosis, we would love to discuss all of the ways that integrative oncology support could help you.

Book an appointment with us now to schedule time to get a comprehensive evaluation and recommendations.