No Meat, Dairy, Added Sugar, or Processed Foods: Will it Help Metastatic Breast Cancer Patients?

Oct. 8, 2018

Thomas Campbell, M.D.Thomas Campbell, M.D., a worldwide bestselling author and authority on nutrition, and a family physician at the University of Rochester Medical Center, is conducting an eight-week pilot study among women with stage 4 breast cancer. Researchers are providing study volunteers three prepared meals a day that meet his criteria for a strict, plant-based diet — and then they will evaluate whether this type of optimal nutrition impacts tumor markers, symptoms, and improves a patient’s quality of life.

Campbell is also collaborating with Wilmot Cancer Institute physician/scientist Richard Moore, M.D., who directs the Gynecologic Oncology Program, to track circulating tumor cells and inflammation in the blood samples of patients in the nutrition study.

Although evidence suggests that healthy diets contribute to general well-being and prevention of many diseases and conditions, little is known about nutrition’s role in advanced breast cancer, Campbell said.

“We have a unique opportunity here in Rochester to explore this aspect,” he said, “as well as a having a motivated population of breast cancer patients.”

Women should not think of lifestyle changes such as a plant-based diet as a singular approach to treating breast cancer, he emphasized. “We don’t have enough science yet. I think people should take very seriously what they eat — but what’s most important is to talk to an oncologist and plan the best treatment. I am an all-of-the-above type of doctor, and I don’t believe in one piece of therapy above another. You have to use all of the tools at your disposal.”

The meals in Campbell’s clinical study include popular whole foods such as oatmeal with blueberries, roasted eggplant meatballs, and quinoa salad. But his approach is not for the faint of heart.

We sat down with Campbell to talk food, psychology, and what people with breast cancer can do to improve their eating habits. Following is an edited version of our conversation.

How important is nutrition if you have breast cancer?

It’s likely to be very important but we clearly need more research. In the meantime, we know that a couple of lifestyle issues are definitely important to breast cancer, particularly post-menopausal breast cancer: excess body weight, alcohol consumption, and, of course, tobacco.

For many types of breast cancer, alcohol and excess body weight are really bad news. For alcohol, there’s really not a lower threshold that’s safe. One study even found that a half a drink a day was associated with a higher risk of breast cancer. I think that avoiding alcohol is really important as part of a diet and lifestyle strategy. And for prevention of breast cancer, we also know that excess body weight is bad news. So, maintaining a healthy weight is important, too.

What is the ideal food plan? How do breast cancer patients make improvements, even if they’re not overweight?

There’s an organization called The American Institute for Cancer Research (AICR) that’s done a lot of coalescing of data, looking at diet and cancer research. Basically, they recommend a plant-based diet, emphasizing fruits and vegetables, whole grains, beans and legumes, and limiting or avoiding red meat and totally avoiding processed meat. They allow small amounts of lean meat, and things like nuts and avocado are fine. You reduce the animal portion of the plate, increase the plant portion, and limit processed foods in general, like white flour, sugar, and fats.

When we talk about ‘’processed foods” I tend to be a bit more extreme than other people. I work with a lot of people and I see so much processed food in our standard American culture. And it’s very tricky and deceptive. They have packages in the grocery store that say “half your servings of whole grains for the day” — and yet 40 percent of the calories come from fat, or too much salt, or refined flour. It gets really hard to negotiate small changes. So, I really encourage people to make big changes. Processed food is a very broad spectrum. On one side you have Reese’s Puffs cereal, and on the other side a “natural” cracker. Right? If you’re switching from tortilla chips to Triscuits, and generally keeping the rest of your diet the same, you’re not helping yourself.

I encourage people to push themselves. People tend to feel virtuous by making small changes because we’re all masters at rationalization. We want to avoid feeling bad about what we do. But you have to be honest with yourself. 

You have to think of your food as a dietary pattern. If anything in your diet comes from an animal, think of it as a condiment. The center of the plate should be whole grains, beans, fruits, and vegetables.

This all makes sense, but is it possible? What if you’re the only one in your family who’s buying into the changes? What can you say to women who face these hurdles?

Yes, I agree there are many barriers.  It is very, very difficult. That’s why we have a 12-week program to provide that support, at least initially. The hardest part is always the first month or two. In some ways it’s easier to jump in and make extreme changes. That’s what we recommend: Jump in the deep end, and it’ll yank you out of your bad habits and bring on new ones.

The most difficult challenge of all is when a woman has a household of people who aren’t supportive of dietary changes. But cancer can be a pretty good motivator, and if she’s motivated enough, she can do it. We have patients who succeed in that situation. It just takes extra work and determination.

In general there’s been a big interest in plant-based and whole-food diets, and there are plenty of resources. But initially it’s daunting because people wonder: What the heck am I going to eat? Where do I find these foods? It’s annoying to start buying a whole list of things at the grocery store that you’re never bought before – but by week three, the hard work is done.

I’m not a psychologist, but in my experience of working with many hundreds of people, I think of this as a Venn diagram. Three elements converge – social factors, which is the first hurdle; our material environment (what we physically see in front of us all the time, such as opportunities to eat junk food); and then our brain chemistry and addiction. A lot of interesting research supports our addiction to fat and sugar, in particular, which is at the core of processed foods. When you have that in-the-dark-of-the-night craving for a chocolate bar, there’s some serious biochemistry at work.

We have to start realizing that it might be better to regard junk food and processed foods as low-grade cigarettes. If you treat those foods like an addiction, you can quit entirely. With tobacco, research suggests that tapering is not as effective as quitting cold turkey. With sugar, it’s probably easier to quit instead of limiting yourself to a little bite of chocolate every night. If you’re going to eat a chocolate chip cookie I’d rather you have a whole one on Sunday, instead of a bite every night. Realize that your brain is sniffing out the calorie-dense stuff all the time. If you indulge that side of the brain regularly, it’s going to win out.

The flip side is that I can’t prove that really big, severe changes to diet are going to help with breast cancer. That’s why we’re doing the study, and meanwhile we’re left in this gray zone. But research has shown that you certainly can’t hurt yourself by eating a healthy, plant-based diet – and you will feel better, too.

We know there are many risk factors for getting breast cancer, such as high exposure to hormones, exposure to growth factors and insulin, and high levels of inflammation. Each of these risk factors gets better if I put you on a plant-based diet. Some people say, “Heck, this is a terminal disease and I want to enjoy myself and not play around with food I don’t like.” And that’s okay. Still, I strongly advise women to pay strict attention to what they eat.

Campbell is co-author of The China Study, a landmark book that explores the link between eating animal products and serious chronic illnesses such as heart disease, diabetes, and cancer. He is also medical director of the Weight Management & Lifestyle Center at UR Medicine’s Highland Hospital. For more information on Campbell’s pilot study for metastatic breast cancer patients, please contact study coordinator Kelly Koch at (585) 341-9921.