Only Two Foods Cause Cancer, Nutritionist Says

Nichole Andrews, RDN, says only two foods raise the risk of cancer, and sugar is not among them.

Andrews is a Washington-based practicing cancer dietitian and nutritionist and the author of the book 'Sugar Does Not Feed Cancer.'

She is also active on social media, where she debunks common myths about cancer-causing foods and shares evidence-based advice for cancer prevention.

In the WellnessPulse interview, Andrews explains what a cancer prevention plate should look like and what foods are unnecessarily demonized.

Q: Can foods cause cancer? If so, what are they?

A: As of now, strong human data indicates that there are only two foods, one of which you can argue is not even a food, that increases cancer risk. It is processed meat and alcohol.

All types of alcohol contain ethanol, which damages cell DNA. Cells in the human body get damaged every day — this is part of being human and aging. However, to reduce cancer risk, we're trying to reduce that amount of damage.

Any consumption of alcohol starts to increase your cancer risk in the liver, breast, colon, stomach, esophageal, and mouth and throat. Truly non-alcoholic drinks containing 0% alcohol are fine.

The other food is processed meats, such as pre-cooked meats, bacon, and deli meats. Their preparation involves long periods of heating or smoking, adding preservatives, all of which raise the risk of colorectal cancer, but not other cancers.

Red meats contain heme iron that may damage the colon. That's why red processed meats like pork, beef, and lamb are going to increase cancer risk even more.

The risk of cancer increases with any consumption of processed meats and alcohol. It may be scary to hear that, but let's also think about thousands of other foods that don't increase cancer risk and are safe.

Q: What animal protein sources would you recommend instead of processed meat? Or should we shift to plant-based protein?

A: You don't have to shift to plant-based protein, although consuming more plants reduces cancer risk. Many people, especially cancer survivors, feel like they have to go vegan to reduce cancer risk. That's not true.

I recommend lean proteins like chicken, turkey, fish, and seafood. You could eat lean cuts of red meat — up to 18 oz of red meat a week is okay, but not more than that. Even though red meats gather heme iron, they still contain some nutrients.

Dairy is a really good choice for protein because it contains calcium, which reduces the risk of colorectal cancer. Another lean, cheap source of protein is eggs. Protein powders and protein beverages are okay as long as they're not fortified with too many micronutrients.

Then, we have all those good plant-based proteins like nuts, seeds, beans, tofu, and soy.

Q: Are some ways of preparing food healthier than others from a cancer prevention perspective?

A: Yeah, absolutely. Some studies suggest that burning meats creates carcinogenic byproducts that could potentially increase the risk of cancer. While it is better not to grill meats, grilling, and burning vegetables and plant-based meat alternatives are safe.

Polycyclic aromatic hydrocarbons and heterocyclic amines are the two carcinogenic byproducts of only animal proteins when they are grilled or cooked for long periods of time.

If you’re grilling meat, try marinating it or pre-cooking it in a pan. Also, make sure that the grill flames don’t touch the meat. You can also try pan-cooking it a little bit before putting it on the grill to finish it.

If you want to grill, choose a high-fiber meal to make sure you have regular bowel movements to remove any carcinogenic byproducts.

Q: There is a common belief that sugar causes or feeds cancer. What's your take on that?

A: It doesn't. Unfortunately, cancer is pretty greedy; it grows and divides fast and doesn't slow down. That's why intense treatments like immunotherapy, chemotherapy, and surgery are needed to kill cancer.

Cancer does uptake carbohydrates, protein, and fat from the body, regardless of whether you eat or not. It is important to eat well during cancer treatment to be really well nourished.

However, altering the diet, removing or reducing sugar, or even starving will not change cancer metabolism; it will not slow down cancer growth.

Technically, cancer has a higher glucose uptake; it will gobble up lots of carbs quicker than your healthy cells, but we can't change that.

Instead, I want patients to focus on eating well for their healthy cells. I'm not promoting a high-sugar diet, but having a birthday cake or a cookie is a normal part of eating.

Having some sugar in your diet, whether you've had or have cancer, is okay; it is not going to cause your cancer to come back or grow quicker.

Q: What does an anti-cancer diet look like?

A: You can build your cancer prevention plate and still love your life, have some sugar and some meat. You can do it during or after cancer treatment.

Two-thirds of your plate or snack should contain plant foods, such as fruits, vegetables, whole grains, nuts, seeds, beans, or legumes. All these plant foods contain antioxidants and phytochemicals that protect cells from damage and repair already damaged cells.

These foods also have fiber, which reduces the risk of colon and breast cancer.

Healthy fat sources are ideal for one-third of your cancer prevention plate. While you can still eat butters and creams, the healthier fats include plant oils, even though they are being demonized.

The healthy fat section can include olives, avocados, and nut seeds, as well as proteins like chicken, fish, turkey, a little bit of red meat, dairy, and eggs. This part should also include the dessert, such as candy or chocolate.

There are things you can do lifestyle-wise: remove alcohol and tobacco and don't take unnecessary supplements.

Supplements are okay if you're low on vitamin D and your doctor prescribed them or if you're pregnant and need folic acid. But don't take supplements to try to make up for food.

Q: Are organic foods always better than conventional foods, especially for cancer prevention?

A: No. Organics use their own type of pesticides, just like conventional does. They both fall within safe levels of pesticide residual.

Many people think organics are better because they don't have pesticides or have better pesticides. That's not true.

Conventional blueberry and organic blueberry have the same nutrient composition, and both have safe levels of pesticide residuals. They are both amazing choices.

Save your money — you don't need organics. It's really about marketing. I just want you to eat more fruits and vegetables.

Q: Some people are selling their nutrition programs promising to cure cancer with food. What would be your message to cancer patients who may be considering replacing regular treatments with such 'miracle diets'?

A: If you consider completely forgoing your doctor's recommendations, I would caution against it. I've seen and heard other survivors who refused chemotherapy and tried to manage cancer with food, which doesn't work.

So what happens then is that cancer grows, the diagnosis progresses, they go back to try to get treatments from the doctor, and they no longer can be treated because it has grown so much.

I would follow your doctor's recommendations to get treatments like chemotherapy, radiation, or immunotherapy. At the same time, use food to nourish your healthy cells because good nutrition will affect your treatment outcomes.

At this time, no diet or fasting regimen can cure cancer, which is a very complex disease.

The takeaway

Only two foods – processed meat and alcohol – have been shown to cause cancer. At the same time, a diet rich in plant foods, such as fruits, vegetables, and whole grains, along with healthy fats such avocados and poultry, may help reduce cancer risk.