There is so much information about nutrition and breast cancer out there… but not all of it is helpful or based on science. As a registered dietitian at a cancer centre and in the media, I get asked tons of questions about nutrition information my clients found online or heard from other people. Here are the most common questions I get asked and the evidence-based answers you need to make the best choices for your health and wellness! Keep in mind these are quick and dirty answers. If you want more details, feel free to tweet me @80twentyrule.
1. Should I cut red meat out of my diet to lower cancer risk?
Eating too much red meat is linked to a higher risk of some cancers. If you do choose red meat, limit the amount to 18 ounces or less a week. To help you visualize that, 3 ounces of meat is roughly the size of a deck of cards. When you do have red meat, it’s also a good idea to go for leaner cuts. This will help you take in fewer calories and less saturated fat, keeping you on track to manage your weight and protect your heart.
If there is a type of meat to totally cut out of your diet, it’s processed meat. Processed meat such as sausages, hot dogs, pepperoni, bacon and deli meats, are sometimes smoked and often contain chemicals called nitrates. Chemicals in smoked meats and nitrates may increase the risk of colorectal cancer, even in small amounts. They are also linked to a higher risk of heart disease and type 2 diabetes. As a result, it’s best to avoid eating processed meats as much as possible.
Why am I letting you know about something that affects your risk of other cancers, heart disease and diabetes instead of just focusing on breast cancer? Going through cancer treatment increases the risk of getting other types of cancers and other chronic diseases. That’s why it is so important to eat well not only to lower your risk of breast cancer, but to prevent other health concerns.
2. Should I eat organic foods to avoid synthetic (man-made) pesticides?
When clients ask me this, I always respond with this question: If you were to only buy organic produce, would that mean you would eat less vegetables and fruits because of the higher cost?
If the answer is yes, I tell them we need to come up with a better solution than eating 100% organic.
The benefits of eating vegetables and fruits outweigh any negative effects of synthetic pesticides. First and foremost, aim for 7-10 servings of fruits and vegetables a day in a variety of colours. This will help you get plenty of cancer-fighting antioxidants, plant nutrients (phytonutrients), vitamins, and minerals. Beyond that, eating organic is a personal choice. If you do want to choose more organic foods, here’s how to make it work for you if cost is a concern:
- Check out the Environmental Working Group’s Dirty Dozen and Clean Fifteen List. This list will show you how to make the most out of your food budget by purchasing organic versions of the “dirty dozen”, or foods higher in chemical pesticides, and conventional versions of foods that tend to be sprayed with less chemical pesticides.
- If you have questions about GMOs (genetically modified organisms) check out my blog post for my take on this issue.
3. Does sugar feed cancer?
The idea that “sugar feeds cancer” comes from the observation that cancer cells in the lab will die when they don’t have sugar. What you don’t hear about: this is also true for healthy cells. Carbohydrates, and even some of the protein and fat in our food, are all eventually turned into sugar (glucose) that our body can use for energy). This means cutting “sugar” out of your diet completely is impossible.
There is a difference between refined carbohydrates and sugars that are added to food and beverages and carbohydrates or sugars naturally found in healthy foods. Refined carbohydrates and added sugars raise your blood sugar levels and can cause cravings and weight gain. These foods are also linked to higher levels of insulin, a hormone that may help cancer cells grow. These refined carbohydrates and added sugars also contain very little nutrition. This is what dietitians call “empty calories.”
Replace refined foods such as sugar and white flour with healthy sugars and carbohydrates such as fruit and whole grains. Natural sugars and carbohydrates found in fruit and whole grains come with fibre, which slows down the digestion of sugar and plays a role in reducing cancer risk. Fruit and whole grains also contain vitamins and phytonutrients, compounds that may reduce cancer risk and help fight cancer.
Eating a diet that is too high in added sugar or refined carbohydrates means you are more likely to be overweight, which is linked to a higher risk of getting breast cancer and of breast cancer recurrence. For good health, limit added sugars to 6-7 teaspoons per day. To help put that into perspective, a can of pop has at least 10 teaspoons of sugar!
4. Is alcohol good or bad if you have breast cancer?
You may have heard that red wine is good for your heart. But what about cancer risk? Alcohol increases cancer risk in large amounts. Women should limit alcohol to 1 standard drink a day, which is 5 ounces of wine, 1.5 ounces of spirits or a 12 ounce bottle of beer. And no, you can’t save them all up for the weekend 😉
5. I heard juicing helps fight cancer. Should I go on a juice fast and for how long?
Fresh juice can fit into a healthy diet, but shouldn’t be used as a meal replacement or as your only source of nutrition. This will put you at risk of nutrient deficiency and loss of lean muscle mass. Juicing also removes the fibre from fruits and vegetables, which is needed for a healthy digestive system, to prevent constipation, and to prevent colorectal cancer, diabetes and heart disease. Removing the fibre means you are left with only carbohydrates or sugar. This could mean you get hungry faster and might produce more insulin (see #3 for more on insulin).
Tips for smart juicing:
- Eat at least 5 servings of whole fruits and vegetables first. Once you meet that goal, you can add juicing as a strategy to get extra servings. If you are on radiation treatment or chemotherapy, check with your doctor or dietitian before adding juicing to your routine.
- Use mostly vegetables with some fruit for sweetness if you are watching calories or sugar intake.
- Try blending fruit or vegetables into a smoothie as a way to include the fibre.
- Have some protein and a bit of healthy fat with your juice for staying power. A handful of nuts or some Greek yogurt are great choices!
6. Should I avoid soy? What about isoflavone supplements?
Enjoy up to 2 servings a day of soy foods and you will not have a higher risk of breast cancer – you may even lower your risk. A serving of soy is 250 mL (1 cup) of soymilk, ¾ cup (175 g) of tofu, 1/3 cup of soynuts or ½ cup of edamame. Choose unprocessed forms of soy such as edamame rather than soy burgers or soy hot dogs. The processed versions are lower in phytonutrients and higher in things we don’t need, like salt and other preservatives. Also, avoid isoflavone or soy supplements. Isoflavones are plant nutrients found in soy that may help fight cancer, but it’s always better to get nutrients from food rather than supplements. You don’t want to get too much of a good thing!
How to find reliable nutrition information
Speak to a registered dietitian who specializes in oncology or find resources written by a dietitian (RD). RDs have a 4 year specialized undergraduate and often a Master’s degree in nutrition, do a 1 year internship where they get hands-on training in nutrition therapy for a variety of diseases and settings, and write a licensing exam. Dietitians are a regulated health profession like doctors and nurses. This means we are part of a college that protects the public. We must give information that is based on the latest scientific evidence. If we give inaccurate information, we can lose our license to practice or pay a fine. “Nutritionists” can call themselves that without any training or education. You deserve the best!
Christy Brissette, MSc, RD
Registered Dietitian and Food and Nutrition Communications Expert
ELLICSR Kitchen, The Princess Margaret Cancer Centre, Toronto