Cancer Diet for Patients

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Cancer patients have unique dietary needs depending on what type of cancer they have and their current treatment plan. Part of eating well with cancer is making sure you’re getting enough calories and nutrients to maintain your strength and energy levels. Here are some tips on how to eat before, during, and after cancer treatment.

Protein-Rich Foods to Eat Before Beginning Cancer Treatment

Theresa Chiechi

Before Cancer Treatment

If you're preparing for surgery, radiation, or chemotherapy, your healthcare provider may tell you to increase your calorie and protein intake beforehand. Doing so provides your body with additional fuel stores for recovery, especially if your appetite goes down after treatment.

It's not uncommon to lose muscle mass and strength during the fight against cancer. With enough protein, you can help prevent this negative side effect.

Aim to have a source of protein with every meal and snack, such as:

  • Dairy: Cottage cheese, Greek yogurt, string cheese
  • Eggs: Omelets, boiled eggs, deviled eggs
  • Meats: Chicken, beef, and pork
  • Nuts: Almonds, pistachios
  • Seafood: Shrimp, grilled or broiled fish fillets
  • Seeds and beans: Chickpeas, black beans, sunflower seeds, peanuts, or peanut butter

Now is a good time to prepare some freezer meals so you'll have healthy options available if you don't have the energy to cook while you're undergoing treatments.

The nutritional issues associated with cancer treatment, particularly reduced appetite, can be related to stress and depression. Finding proactive ways to manage stress before undergoing treatment will equip you with tools to rely on if treatment becomes difficult.

These may include deep breathing, meditation, stretching, swimming, reading, writing, or connecting with others who can relate to your situation.

During Cancer Treatment

Talk to your healthcare provider before starting cancer treatment so you have some idea of what to expect. Everyone reacts to cancer treatments differently, so it's best to take it one day at a time and manage symptoms as they come.

Managing Side Effects

Common side effects of cancer treatment may include:

Fiber is essential for regularity. Good sources of fiber include foods like oatmeal, beans, fruits, and vegetables. If you're having trouble eating enough high-fiber foods, a fiber supplement can be helpful. Speak to a dietitian to determine if a fiber supplement is necessary, and make sure you're drinking enough fluids to support good digestion.

If your mouth is sore, choosing softer foods can help you avoid pain while eating. Your healthcare provider should be able to recommend a saltwater rinse that you can use several times per day. You also be able to use a numbing spray in your mouth when eating if needed.

For low energy, fatigue, and poor appetite, physical activity can help. Although you may feel tired, pushing yourself to go outside for a short walk or do some home exercises can help you get your energy levels and hunger cues back.

Choosing small, frequent meals and foods that don't have a strong smell can make it easier to keep nausea at bay. If you're struggling to swallow or aren't able to eat for more than one day, talk to your practitioner so they can come up with a plan to address these issues.

To avoid significant weight loss, you may need to focus on packing in extra calories. The strategies recommended to boost your calorie intake may go against dietary advice you've been given in the past, so you'll need to reconsider the way you view healthy eating during treatment.

For example, you may be advised to use more butter, cheese, and gravies. Your healthcare provider may suggest ice cream after dinner or extra peanut butter and sauces. Keep an open mind and let go of a restrictive eating mindset if advised to bulk up your calorie count.

Sometimes modified textures or a temporary tube feeding can be the right solution to help your body while getting through cancer treatments.

A dietitian can help you find individualized strategies to manage cancer treatment side-effects so you can get the nutrients your body needs.

Can Foods Reverse Cancer?

Several diet books have claimed to know the secret to cure cancer. However, it's more accurate to view nutrition as a means to help you feel your best for treatment and reduce the spread of existing cancer. Overly restricting your intake of certain foods by going on a "cancer diet" may put you at a disadvantage when struggling to take in an adequate number of calories.

Popular diets among cancer patients include the macrobiotic diet, the paleo diet, the ketogenic diet, and vegan diets. Unfortunately, none of these dietary strategies are definitively proven to reduce the rate of cancer spread or mortality in humans.

Needlessly limiting your intake of fiber, protein, or antioxidants as the result of dietary restrictions may do more harm than good.

Antioxidants present in foods (like vitamin C in fruits and vitamin E in nuts) can help protect your healthy cells. However, these foods are not necessarily beneficial when taken in supplement form and cannot reverse cancer.

While sugar is often vilified as a cancer-promoter, it seems that excess weight gain as the result of a high-sugar eating plan is more likely to cause an issue (especially for weight-related cancers, like breast cancer). Focus on making your calories count, rather than choosing empty calories from sugary foods with no redeeming qualities.

For instance, if a protein shake with added sugar is the only way you can tolerate getting some protein in, you shouldn't turn it away because of the sugar content. It's more important to give your body what it needs even if it comes with a little extra sugar.

After Cancer Treatment

Once you complete cancer treatment, your healthcare provider can advise you on any specific dietary restrictions to keep in mind. Aim to avoid alcohol and processed meats. These items are known carcinogens and have little to offer for recovery and good health.

Choose a range of nutrient-dense foods to replenish your body's energy stores and fuel a healthy lifestyle. Continue to focus on foods that are naturally high in fiber to support your digestive system.

If you're required to follow a modified diet (with thickened liquids, for instance) a dietitian can recommend specialty products and cooking tips to incorporate into your favorite foods and beverages.

Depending on your individual goals, your healthcare provider may want you to work on weight loss or weight gain. Adjusting your calorie intake while still taking in a sufficient amount of protein will help you reach your goal while still building back your strength.

A Word From Verywell

The journey through cancer treatment is different for everyone, so don't let your worries get the best of you when preparing for the road ahead. Manage your anxiety by taking cancer treatment one step at a time.

Your team of healthcare professionals, including speech and language pathologists, nurses, dietitians, and therapists, can support you with effective strategies to face challenges as they arise.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. NIH National Cancer Institute. Eating hints: before, during, and after cancer treatment.

  2. Zick SM, Snyder D, Abrams DI. Pros and cons of dietary strategies popular among cancer patientsOncology (Williston Park). 2018;32(11):542-547.

  3. Academy of Nutrition and Dietetics. Antioxidants - protecting healthy cells.

  4. Espat A. University of Texas MD Anderson Cancer Center. Does sugar cause cancer?.

  5. American Cancer Society. Eating well after treatment.

By Anastasia Climan, RDN, CD-N
Anastasia, RDN, CD-N, is a writer and award-winning healthy lifestyle coach who specializes in transforming complex medical concepts into accessible health content.