Nausea, vomiting, and mouth sores are all common side effects of breast cancer treatment. When you feel sick to your stomach and your mouth hurts, you may start to dread mealtimes.

Yet eating a balanced diet is especially important when you have breast cancer. Proper nutrition helps your body heal from treatment. Eating right will keep you at a healthy weight and help preserve your muscle strength.

If you’re having difficulty eating enough, use these tips to get more nutrition into your daily diet.

Certain food choices are better than others for people with breast cancer. Here’s a quick guide.

  • Fruits and vegetables. Brightly colored fruits and vegetables are high in plant nutrients called phytochemicals. Cruciferous vegetables like broccoli, cauliflower, kale, and Brussels sprouts may be especially good choices because they have antiestrogen properties. Berries, apples, garlic, tomatoes, and carrots are also beneficial choices. Try to eat at least five servings of fruits and vegetables daily.
  • Whole grains. Whole-wheat bread, oatmeal, quinoa, and other whole grains are high in fiber. Eating extra fiber may help you avoid the constipation that certain cancer drugs can cause. Try to eat at least 25 to 30 grams of fiber daily.
  • Lentils and beans. These legumes are high in protein and low in fat.
  • Protein. Choose healthy sources of protein, which will help keep your body strong. Examples include skinless chicken and turkey breasts, and fatty fish such as tuna and salmon. You can also get protein from nonanimal sources like tofu and nuts.

On the other hand, there are certain types of foods you should consider limiting or avoiding completely. This includes:

  • High-fat meats and dairy products. These foods are high in unhealthy saturated fats. Limit fatty red meat (burgers, organ meats), whole milk, butter, and cream.
  • Alcohol. Beer, wine, and liquor could interact with the cancer drugs you take. Drinking alcohol is also a risk factor for the development of breast cancer.
  • Sweets. Cookies, cake, candy, sodas, and other sugary treats cause weight gain. They’ll also leave less room in your diet for healthy foods.
  • Undercooked foods. Cancer treatments can make your white blood cell count drop. Without enough of these immune-fighting cells, your body is left more vulnerable to infections. Avoid raw foods like sushi and oysters during your treatment. Cook all meats, fish, and poultry to a safe temperature before eating them.

If you’ve been reading up on breast cancer, you might have come across stories online claiming that one diet or another can cure you. Be wary of these highly exaggerated claims.

Certain types of eating plans — like the Mediterranean or low-fat diet — might help improve the outlook for some people with cancer. One study linked a low-fat diet to better odds of survival after a breast cancer diagnosis.

In contrast, the ketogenic diet is a high-fat, low-carbohydrate eating plan that has gained recent popularity. You dramatically cut carbohydrates to put your body into a state of ketosis, where it’s forced to burn stored fat for energy.

Though a few studies have shown the ketogenic diet to be promising for certain types of cancer, it hasn’t been proven to treat breast cancer. And it can alter the chemical balance in your body, which could be risky.

Any diet you try should contain a healthy balance of nutrients, protein, calories, and fat. Going too extreme could be dangerous. Before you try any new diet, check with your dietitian and doctor to make sure it’s safe for you.

A plant-based diet means that you mainly eat foods like fruits, vegetables, grains, nuts, and seeds. This is similar to a vegetarian or vegan diet, but many people who follow plant-based diets still eat animal products. However, they limit their intake.

The American Institute for Cancer Research recommends following a plant-based diet for cancer prevention. Their research shows that cancer survivors may benefit from this diet as well. This diet allows you to receive fiber, vitamins, minerals, and phytochemicals from plant foods, while also getting protein and nutrients from animal products.

Aim to fill two-thirds of your plate with plant foods, and one-third with fish, poultry or meat, or dairy. Try to avoid or limit red meat and processed meat.

Eating a healthy diet is beneficial if you’re living with breast cancer, especially during and after cancer treatment. Good nutrition keeps your body healthy and strong, and helps you feel better quicker.

A healthy diet can help you:

  • maintain a healthy body weight
  • keep body tissue healthy
  • lessen cancer symptoms and side effects of treatment
  • keep your immune system strong
  • maintain your strength and reduce fatigue
  • improve your quality of life

Breast cancer symptoms and treatment side effects may leave you feeling too unwell to cook, plan meals, or eat as you normally do. Here are some tips to help make eating healthy easier.

Shrink the size of your meals

Nausea, bloating, and constipation can make it hard to eat three large meals a day. To get the calories you need, graze on smaller portions five or six times daily. Add snacks like granola bars, yogurt, and peanut butter on crackers or apples.

Meet with a registered dietitian

A dietitian can help you design a healthy meal plan that fits with your food preferences and nutritional needs. They can also teach you ways to manage cancer treatment side effects like nausea so that you can eat a more well-balanced diet.

If you can, work with a dietitian who has experience in treating people with breast cancer. Ask your oncologist or nurse to recommend someone.

Use different utensils

Sometimes chemotherapy can leave a bad taste in your mouth that gives food an unpleasant flavor. Certain foods — like meat — can take on a metallic taste.

To improve the taste of your food, avoid metal utensils and cooking implements. Use plastic cutlery instead and cook with glass pots and pans.

Plan and prepare meals ahead of time

Cancer treatment can take up a lot of your day and leave you feeling exhausted. Meal prep can help make eating easier. Also, if you prepare your meals ahead of time, you’re more likely to stick to a healthy eating plan.

Create a meal plan for the entire week. Ask your dietitian to recommend healthy, cancer-friendly recipes, or find suggestions through organizations like the American Cancer Society.

Cook an entire week’s meals over the weekend when you have more time. If you’re too tired to cook or you can’t stand the smell of it, ask a friend or relative to prepare meals for you.

Add more fluids

If your mouth hurts too much to eat solid foods, get your nutrition from liquids. Drink smoothies or nutritional beverages.

In addition, treatment side effects like vomiting and diarrhea can dehydrate you. Try to drink at least 2 to 3 liters of water, fruit juice, and other caffeine-free beverages each day. If you feel nauseated, drink herbal tea with ginger or peppermint to settle your stomach.

Eating a nutritious diet when you have breast cancer has many health benefits. Not only can it make you feel better faster, but it can boost your immune system and keep you strong. If you’re considering trying a new diet or are having trouble sticking to a healthy eating plan, talk to your doctor or a dietitian.

It might also be helpful to reach out to others for support. Our free app, Breast Cancer Healthline, connects you with thousands of other women living with breast cancer. Ask diet-related questions and seek advice from women who get it. Download the app for iPhone or Android.