Eating Well During Breast Cancer Treatment

Medically Reviewed by Hansa D. Bhargava, MD on March 17, 2020
5 min read

When you’re being treated for breast cancer, your priority is to stay as healthy as you can. A healthy diet can help give you the strength you need to get through the process.

But side effects from chemo, radiation, or medication can make it hard to eat well. You may have days when you don’t feel like eating anything, or don't like the smell or taste of certain foods. Other days, you might feel fine. You can’t predict how the treatments will affect you.

Your best bet is to plan for days when you feel bad, and adapt your diet to suit your symptoms.

To maximize nutrition, cut back on processed and prepackaged foods. Instead, opt for nutrient-dense whole foods like fruits, vegetables, whole grains, and lean proteins.

If you're unsure how to get started on a healthy diet plan or have dietary restrictions, talk to your doctor or a dietician. But here are some basics:

  • Choose whole grains like brown rice, quinoa, whole wheat, rye, oats, corn, bulgur, and barley.
  • Have fresh fruits and/or vegetables at every meal. Experts recommend at least five servings daily.
  • Include cruciferous vegetables like broccoli, cauliflower, kale, cabbage, and Brussels sprouts. They're rich in plant chemicals that may have cancer-fighting properties.
  • Eat green leafy vegetables like lettuce, spinach, Swiss chard, beet greens, and romaine.
  • Get extra protein from soybeans, peas, chickpeas, lima beans, peanuts, dried beans, and lentils. While you're having treatment, you need half a gram of protein daily for each pound you weigh.
  • If you eat meat, choose lean options like chicken and fish. Fatty fish like salmon and tuna contains omega-3 fats thought to help limit the growth of breast tumors.
  • Avoid pickled, cured, or smoked foods, which tend to have lots of salt and additives.
  • Keep fats to about 30% of your daily calories.
  • Limit alcohol. Some studies have found a link between drinking alcohol and breast cancer. And it has calories, but few nutrients.
  • Drink eight glasses of water a day to stay hydrated.

Nausea and vomiting are common side effects of chemotherapy and radiation. Some medications can cause them too. If they affect you, try these techniques:

  • When you feel nauseous, don't force yourself to eat. Give yourself a break for 4-8 hours until you feel better.
  • To settle your stomach, sip water or flat ginger ale.
  • After you vomit, you need to replace the fluids and nutrition you lost. Chicken or vegetable broth, or a sports drink with electrolytes, can help you hydrate.
  • Eat small, frequent meals. Aim for six to eight per day.
  • Rinse out your mouth with water before and after you eat to take away any bad tastes.
  • Snack on dry, bland foods like crackers, toast, or cereal.
  • If you don't feel like eating, get some nutrients by sipping 100% natural fruit juices.
  • Stay away from sweet, greasy, spicy, or fried foods that can further upset your stomach.
  • Avoid foods with strong smells that can make your nausea worse.

Don’t go too long without eating something. If cooking smells make you nauseated, ask family members or friends to cook for you. Or look for healthy options in restaurants that you can order to go or have delivered.

Breast cancer treatment can affect your senses of taste and smell. Foods you used to enjoy may seem bitter or rancid. Many people who go through chemotherapy say food tastes "metallic."

This can last a few weeks or months, even after treatment ends. To deal with it, change up your routine:

  • If the foods you usually eat don’t taste right, try different ones.
  • Eat a light meal a few hours before each treatment.
  • Use plastic utensils to avoid a metallic aftertaste.
  • Eat foods cold or at room temperature instead of hot.
  • Try fruit smoothies, which don't have strong smells or tastes.

Getting enough protein, liquid, and calories can help with the fatigue breast cancer treatments can cause. But if you sometimes feel too tired to cook or eat:

  • Eat your biggest meal at the time of day you feel best.
  • Snack throughout the day on healthy, convenient foods like string cheese, raisins, baby carrots and hummus, or yogurt.
  • When you're feeling energetic, cook a big batch of soup, pasta, or a casserole. Freeze in serving-size containers to reheat when you don't feel like cooking.
  • If you're just not up to a full meal, substitute an energy bar or nutritional drink.

Chemo or radiation can make it harder for your body to defend itself from infections. If you eat food that's spoiled or contaminated, you can get very sick.

Follow these food safety steps when you cook or eat:

  • Wash your hands with soap before and after you handle food.
  • Keep refrigerated foods at 40 degrees or below.
  • Don’t thaw meats or fish at room temperature. Use a microwave or let them thaw in the refrigerator.
  • Never refreeze thawed foods.
  • Don't keep perishable foods out of the fridge for more than 2 hours. If they contain eggs, cream, or mayonnaise, don't leave them unrefrigerated for more than an hour.
  • Use running water to wash all fruits and vegetables, even those marked "prewashed."
  • When cooking, use separate utensils for stirring and tasting.
  • Avoid rare or medium-rare meat and runny egg yolks.

Food is always the best way to get nutrients. But when treatment side effects make it hard to eat well, a multivitamin could fill in some of the gaps.

You can buy hundreds of types of dietary supplements. But the FDA doesn't regulate them. And some may do more harm than good. If you take large doses of vitamins and minerals, it could make chemotherapy or radiation less effective.

Before you take any supplement, talk to your doctor or a dietician. Follow their instructions for dosages as well as what type to take.