Metastatic breast cancer (MBC) treatment often brings challenging side effects like nausea, fatigue, mouth sores, and constipation, which can severely impact appetite and nutrition. Maintaining adequate calorie and nutrient intake is crucial for energy levels, immune function, and preventing treatment interruptions. Small adjustments to diet—food choices, textures, timing—can make a significant difference, but consulting an oncology dietitian is essential for personalized guidance.
Managing Nausea During Treatment
Nausea is a common and frustrating side effect. When appetite is suppressed, focusing on bland, easily digestible foods is key. Saltine crackers, white toast, plain pasta, applesauce, and bananas are good starting points. Eating something small before getting out of bed can also help settle the stomach.
Instead of three large meals, opt for six to eight smaller meals throughout the day. Examples include white toast with peanut butter and banana, or shredded chicken with mashed sweet potatoes. Smoothies provide a convenient way to consume calories and nutrients when solid food is unappealing, blending in banana, nut butter, oats, or protein powder.
Ginger tea, chews, or ale may alleviate nausea, but avoid if the flavor is unpleasant. Minimizing strong food smells—cooling meals before eating or choosing fridge-cold options—can also help. Ventilation and using lids/straws for drinks further reduce odor impact.
Avoid: fried/greasy foods, spicy dishes, sugary drinks, and high-insoluble-fiber foods (whole grains, raw broccoli) until nausea subsides.
Addressing Mouth Sores and Painful Eating
Mouth sores make chewing and swallowing painful. Prioritize soft, moist foods to minimize irritation. Applesauce, yogurt, mashed potatoes, and soft cooked vegetables are good choices. Add broth, soups, sauces, or purees to make swallowing easier.
Soft protein sources like tofu, creamy nut butters, scrambled eggs, and smooth hummus are often better tolerated. Smoothies can be customized with peanut butter, bananas, berries, Greek yogurt, or even a small scoop of ice cream for extra calories.
Experiment with food temperature; some patients prefer warm foods for soothing, while others find cool foods more comfortable.
Avoid: acidic foods (tomato products, citrus juices), citrus fruits, spicy foods, and crunchy/sharp foods (chips, crackers).
Strengthening Immunity During Treatment
MBC treatment often weakens the immune system. Supporting it through nutrition is crucial. Protein (chicken, fish, eggs, beans, lentils) is essential for tissue repair and antibody production. Omega-3 fats (salmon, walnuts, chia seeds) reduce inflammation.
Vitamins A, C, D, and E play vital roles in immune function; obtain them from sweet potatoes, citrus fruits, fatty fish, and nuts/seeds. Focus on whole foods over high-dose supplements unless a deficiency is confirmed by your care team. A plant-rich diet (two-thirds of your plate) with lean protein provides optimal nutrients.
Gut health is critical. Consume oats, beans, berries, leafy greens, and whole grains to support beneficial gut bacteria. Practice safe food handling: wash produce thoroughly, use separate cutting boards, reheat leftovers fully, avoid expired foods, and consume pasteurized dairy/juices.
Avoid ultra-processed foods (prepackaged snacks, sugary cereals, processed meats) that lack nutrients.
Managing Joint Pain and Inflammation
Inflammation from MBC treatment can cause joint pain. An anti-inflammatory diet can help. Berries, leafy greens, and cruciferous vegetables (broccoli, cauliflower) provide antioxidants and compounds to regulate inflammation.
Include whole-soy foods (tofu, tempeh), mushrooms, healthy fats (olive oil, avocados), and spices (turmeric, ginger). These ingredients have anti-inflammatory properties.
Combating Fatigue Through Diet
Fatigue is prevalent during MBC treatment. Prioritize calories, protein, and hydration. Combine protein and carbohydrates for stable blood sugar (oatmeal with nut butter, smoothies with soy milk/banana/protein powder, beans and rice). Ensure adequate iron/folate intake through lentils, beans, leafy greens, and fortified cereals.
Anti-inflammatory foods can also reduce cancer-related fatigue. Sip fluids consistently; dehydration worsens fatigue. Opt for low-prep options when energy is low: premade smoothies, yogurt, string cheese, or precut fruits/vegetables.
Relieving Constipation From Treatment
Treatment medications can cause constipation. Combine that with reduced appetite or activity, and your digestive system slows down. Focus on high-fiber foods (fruits, vegetables, beans, whole grains) and adequate hydration. Prune juice or fiber supplements can help.
Regular physical activity (even gentle walking) also stimulates bowel movements. If constipation persists, talk to your doctor about safe stool softeners or laxatives.
By prioritizing these nutritional strategies, patients undergoing MBC treatment can better manage side effects, maintain energy levels, and improve their overall quality of life. Collaboration with an oncology dietitian is crucial for tailoring these recommendations to individual needs and treatment plans.
