Eat More Plants

Cancer Prevention Strategies: Adopt a Plant-Forward Plate with Oncology Dietitian Carol Sullivan

October is Breast Cancer Awareness Month. 

To provide unique insight into this complicated disease, we sat down with Carol Sullivan, Senior Clinical Oncology Dietitian, to pick her brain about the correlation between oncology and nutrition.

FLIK Hospitality: What is your experience specific to nutrition and cancer prevention?

Carol: I have been working in cancer prevention for 10 years. I see patients anywhere along their treatment journey, starting right after [cancer] diagnosis, so I generally wouldn’t see people for prevention, more for prevention of recurrence

 FLIK: Obviously, genetics play a large factor in cancer risk. What role does nutrition play in risk and prevention?

C: From a recommendation for of cancer prevention, really the biggest thing I work on with people is weight loss since we know that having more body fat is related to or a potential cause of multiple kinds of cancer. There are a lot of cancers that have direct links to being overweight. It’s tough because I’m a strong believer in intuitive eating and “healthy at all sizes,” but unfortunately the research doesn’t always point that way when it comes to cancer.

Another thing to think about is not just body fat, but also waist circumference. For women, waist circumference of more than 31½ inches and for men more than 37 inches is considered to be an increased risk for cancer.

Aside from body fat, trying to get people to move more is huge. So I do a lot of coaching around what people like to do and what they can get themselves to do to move more.

FLIK: If someone is overweight or obese, is there a percentage of weight loss that is most beneficial for cancer prevention?

C: I think the weight loss is so individualized – I don’t know if I can put a percentage on it. We know that a 5-10% loss of body weight can really lower your risk for diabetes, hypertension, and other chronic diseases. So if I had to put a number on it, that would be it. 

Carol Sullivan Rd Cso

FLIK: What approach do you typically recommend for someone who is thinking about losing weight in connection to cancer prevention?

C:  There isn’t one specific nutrient or food that is going to help prevent cancer, but there’s mounds of evidence showing that eating a predominately plant-based diet can protect against cancers at many different sites. So that’s usually my approach for weight loss -- a combination of intuitive eating and getting in touch with why you’re eating, how full you are, and really incorporating as many whole foods as possible and trying to get all that good fiber from plant foods.

FLIK: Do you find people are ready and willing to adopt a plant-forward lifestyle? How do you sell them on it?

C: I encourage patients to get creative with the way they’re cooking and what different flavors they can add from herbs and spices and different grains and different vegetables. I talk to people about how they can add more acid into their food and season their food to make it taste better.

And then, along the way, having some education around how powerful plant foods really are and the amount of phytochemicals, vitamins, and minerals that they contain to protect against cancer. I think talking about some of the research can really sell people on trying to make it a goal to include more fruits and vegetables, whole grains, and herbs and spices into their diet. That mindset of “what can I include” can be more helpful than “what must I stay away from.”

FLIK: What new cancer-preventing foods should we know about and why?

C: I don’t think there’s anything new, but I can talk about some of the trendy foods. 

Turmeric is definitely one of the trendy anti-cancer foods right now and there is a lot, a lot, of research behind it. So I do encourage people to use it in their cooking [when appropriate], but it can interfere with some cancer therapies.

Specifically with the breast cancer population, I’ll always talk about cruciferous vegetables. We know that the sulfur component of cruciferous vegetables has a lot of anti-cancer properties. Specifically for women too, green tea is recommended, 2-3 cups a day. The polyphenols in green tea may protect against breast, ovary, and endometrial cancers.

And then the allium family – so beans, garlic, onions, and shallots – I talk about how much flavor those can add to a meal and how to incorporate them because they have a lot of anticancer and antioxidant properties.

And a general recommendation of a total of at least five servings of fruits and vegetables a day… that’s usually a good place to start. 

Spice Display

FLIK: On the flip-side, are there any cancer-causing components in our diets that we should be aware of?

C: If you think about grilling -- the heterocyclic amines that are formed when you grill is a good example of carcinogens that can be in our food.

And then there’s also some thought that just in general, red meat alone can influence cancer because the heme iron can potentially lead to the production of free radicals and that can do some oxidative damage to DNA.

So red meat alone, I always try to encourage less meat for the week plus lower fat red meat and then, if possible, grass-fed for the higher amount of omega-3s.

And then alcohol, of course. The ethanol in alcohol is classified as a human carcinogen. Technically, if you really wanted to avoid anything that could be a potential promoter of cancer, completely avoiding alcohol would be the recommendation. Even the recommendation for heart health – so one drink a day for women and two drinks a day for men – is too much.

FLIK: Happy weekend!

C: I know! This is a big one, myself included! Trying to kick your habit of not having a glass of wine at night. I do talk about using organic tart cherry juice in a wine goblet because it has that viscosity of a good red wine, the color of a good red wine, and it has a little bit of melatonin in it to help with sleep. There’s a lot of good anti-inflammatory properties of tart cherry juice. 


Next week, Carol busts some common misconceptions for us about nutrition and cancer prevention. Stay tuned! 

You can read more about Carol here


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Edited by Anissa Amirouche, Dietetic Intern