There’s no shortage of advice about what to eat to reduce breast cancer risk, but what about when you already have a breast cancer diagnosis? The symptoms of breast cancer (like weight loss) and side effects of treatment (including fatigue and changes to your taste buds) can make nutrition challenging for people with breast cancer. Maintaining a healthy diet as you undergo treatment can help supply your body with the nutrition that it needs, so it’s important to know what you should eat and what foods you should avoid.

Read on to learn what the latest cancer research tells us, and find out how others living with breast cancer manage their eating habits.

Foods To Eat When You Have Breast Cancer

Nutritional needs, flavor preferences, and cultural backgrounds related to food vary from person to person. Generally speaking, some of the best foods for people with breast cancer are high in fiber, omega-3 fatty acids, and antioxidants. It is important to take in enough calories so that you do not lose weight. It is also important to discuss your diet — especially supplements, if you are taking them — with your health care team. Certain kinds of chemotherapy may be affected by supplements such as antioxidants. In addition, getting adequate protein through seafood, eggs, and poultry will help maintain your strength and muscle mass through treatment.

Research is mixed on the connections between diet and breast cancer. Higher intakes of vegetables, fish, and olive oil (as seen in Mediterranean diets) appear beneficial. There is a weak association between fruit consumption and breast cancer survival rates. Specific fruits, including pomegranate, citrus, and mangosteen, have been shown to have anticancer effects by inhibiting the growth of breast cancer cells.

Some studies indicate that the isoflavones in soy foods, such as tofu and soy milk, can improve breast cancer outcomes. However, soy remains somewhat controversial since there is also research indicating opposite (adverse) effects; soy can have a weak estrogen-like effect in the body. Until more studies are conducted, it’s probably best to continue eating soy in moderation rather than purposefully removing or increasing it in your diet.

Potentially beneficial ingredients to cook with include:

• Black cumin
• Black pepper
• Cruciferous vegetables, such as bok choy, Brussels sprouts, and kale
• Flaxseed
• Garlic
• Ginger
• Mushrooms (including oyster and lingzhi mushrooms)
• Red chili peppers
• Saffron
• Turmeric

Whole grains and legumes, such as beans, edamame, and lentils, can provide the 25 to 30 grams of fiber recommended to promote a healthy body weight and immune system. A simple way to improve your diet is to opt for whole wheat instead of refined flour, as well as low-fat dairy over full-fat products. For a hot or iced beverage, try green tea. Green tea contains compounds that help support the effectiveness and reduce the harmful side effects of breast cancer treatments like radiation and chemotherapy.

Foods To Avoid When You Have Breast Cancer

Diets that are high in saturated fat and trans fats (found in fried food), red meat, and refined sugars are associated with increasing risk factors for women with breast cancer. Since drinking alcohol is associated with higher estrogen levels and an increased risk of breast cancer, it’s recommended that people who have breast cancer do their best to avoid it.

MyBCTeam members share tips on how to reduce their symptoms and improve their quality of life through nutrition. A popular topic of conversation is the effect of food on hot flashes.

“Has anyone who is taking a hormone blocker or going through menopause noticed a correlation between the severity of hot flashes and their diet?” one MyBCTeam member asked. “I heard caffeine makes them worse, and I don’t drink coffee, so I am OK there. I noticed hot flashes are worse for me with chocolate, candy, ice cream (not all dairy items), and alcohol.”

Other members confirmed these suspicions: “Yes, caffeine makes the hot flashes worse. I do drink coffee, but I limit how much. Alcohol and chocolate also seem to make them worse, so I tend to avoid them.”

Another MyBCTeam member said, “Yes, there are foods that can trigger hot flashes, like caffeine, chocolate, and spicy food. But that doesn’t mean you have to avoid them altogether. A little of everything in moderation is just fine.”

Navigating Treatment Side Effects

Members of MyBCTeam ask how others are dealing with the side effects of treatment.

One member asked, “Has your taste for different foods changed? I loved pizza and fried chicken, but now the smell of either makes me nauseated. Eating either is out of the question. My hospice nurse said cancer would do that.”

“My taste in food changed, but I think it’s more mental than physical in my case,” wrote another member. “I have another procedure before I start treatment, and I’m gravitating toward healthier foods because I think it’ll help me recover more quickly.”

“Anything cherry I hate now! It tastes like Vicks NyQuil 🤮,” another member shared. “Salt on certain things ruins the food for me, which isn’t a bad thing since I already have high blood pressure. So, that is a good change in my mind. Also, I eat way more fresh herbs than I used to. It helps with constipation from all these darn meds. Metamucil tastes nasty to me, and the greens seem to work better. What do you guys crave most?”

“I’m currently addicted to frozen fruit, especially mangoes and bananas. I can’t get enough. These also help with constipation,” a member said.

Those who struggle with a poor appetite and food aversions may benefit from bland, cold foods. Smaller snacks spaced throughout the day can be easier to tolerate than larger meals. Avoid filling up on liquids with meals, but consider high-calorie smoothies and shakes to supplement your intake if needed.

Another potential side effect of chemotherapy is a lower white blood cell count. As a result, you may be at higher risk of food poisoning. If your white blood cell count is low, take extra precautions when preparing and choosing your food to avoid foodborne illness.

Post-Surgery Nutrition Tips

Members of MyBCTeam often reach out to see how others feel on a particular medication or after a procedure. One member who was having a mastectomy asked, “What foods have you eaten post-surgery? Is it just liquids for the first week?”

Others responded with their experiences. “You can eat wherever you want, but the liquids would be good because if you eat heavy food, you’re going to get constipated, especially if they give you meds,” replied one member. “Just watch what you eat with heavy foods.”

“You eat whatever you please, lovely lady!” another member said. “I was home on my couch eating peanut butter toast five HOURS after my mastectomy. Protein helps with healing, so just keep up with your usual balanced diet as best you can! Painkillers can also be tough on the tummy. Eating something fairly substantial can help with that.”

Because post-surgery pain medications can cause constipation, health care providers encourage high-fiber foods like bran and prunes paired with plenty of fluids. Once the anesthesia wears off and your doctor says it’s OK, you should be cleared to eat normally.

Nutrients That Promote Healing

Protein is essential for wound healing after surgery, so getting enough protein through food or supplements can help you get back on your feet faster.

Additional nutrients to consider include:

• Vitamin A and carotenoids — Can be found in bright orange and dark green veggies, such as pumpkin, sweet potatoes, and leafy greens
• Vitamin C — Can be found in fresh fruits and some vegetables
• Zinc — Can be found in eggs, whole grains, and fortified grains

A multivitamin may help support your nutritional needs, but megadose vitamins can be harmful. They should not be taken without your health care provider’s approval.

Talk With Others Who Understand

MyBCTeam is the social network for people with breast cancer and their loved ones. On MyBCTeam, more than 53,000 members come together to ask questions, give advice, and share their stories with others who understand life with breast cancer.

Are you living with breast cancer? Do you follow a special diet or have meal-planning tips? Share your experience in the comments below, or start a conversation by posting on your Activities page.