Cancer Cancer Education Featured Food & nutrition

Drink for your health: what should I drink when I have cancer?

We hear a lot about what to eat and what not to eat (for people with cancer and for those without). But it’s also important that we talk about what to drink.

Drinking enough fluids keeps you hydrated and prevents dehydration. Fluids help your body:

  • Digest food and carry nutrients throughout your body
  • Get rid of waste and flush out medications (including chemotherapy)
  • Keep a normal blood pressure and body temperature
  • Protect your organs and joints

Unless told otherwise by your doctor, people with and without cancer should aim for 9 to 12 cups of fluid each day.

It’s important to talk about what to drink because the type of fluids you choose can help you meet your protein and calorie needs. Fluids range in their nutrition content. Some fluids, like water, have no calories or protein, whereas others, like milk or soy milk, have lots. Choosing the right fluids can help you get the right amount of nutrition, depending on your needs.

When you have cancer, getting enough fluid, protein, and calories is an important part of your treatment and healing. If you have lost weight, have problems eating, or have questions about your nutrition, please speak with a registered dietitian. (Patients at the Odette Cancer Centre can stop by or call the Nutrition Resource centre to book an appointment.)

As a registered dietitian in the patient education program at Sunnybrook’s Odette Cancer Centre, I get many questions about what to drink. I answer some of the most common ones below.

As a person with cancer, why is what I drink especially important?

If you have cancer, choosing the right fluids is one of the easiest ways to add more protein and calories to your diet. Side effects from cancer and treatment can make it hard to eat enough. If you find swallowing painful or have a poor appetite, nutritious fluids like soups and smoothies pack a lot of nutrition into each sip and go down easier than a meal. This is important, because getting enough protein and calories can help you:

  • Maintain your weight and muscle mass
  • Keep your strength and energy
  • Cope with treatment-related side effects
  • Reduce your risk of infection
  • Heal and recover faster

Swapping out low-nutrient fluids for high-nutrient alternatives can make a big difference. If you drink 1 cup of water in the morning but switch to 1 cup of milk, that’s an extra 9 grams of protein and 130 calories added to your day!

Are there any types of fluids I should drink lots of?

If you have lost weight, have problems eating, or need more protein in your diet, drink lots of fluids that are high in protein and calories. Choosing higher fat dairy products, like homogenized milk or cream, can also help you get more calories in each sip.

Examples of high protein and high calorie fluids include:

  • Cow, soy, or pea milk
  • Smoothies with added protein
  • Soups made with cream, meat, fish, poultry, or legumes (dried beans, peas, or lentils)
  • Yogurt drinks
  • Nutrition supplement drinks like Boost, Ensure, Scandishake, or generic store brands

If your weight is stable, you have a good appetite, and you are eating enough protein, choose low-calorie fluids more often, like:

  • Water
  • Tea and coffee
  • Broth

Are there any types of fluids that should be avoided?

If you have side effects from treatment, avoiding certain fluids might help. If you have diarrhea, for example, sugary drinks like juice or pop can make it worse. If you feel nauseous, high-fat fluids like cream soups might not be appealing. If you have pain when swallowing, avoid fluids with acidic or spicy ingredients, like lemon or cayenne pepper. Speak to a dietitian for more tips on how to manage side effects that are impacting your eating or drinking.

It’s also recommended to limit your caffeine intake to 400 mg each day, to prevent side effects like difficulty sleeping, headaches, and nervousness. That is equal to about 3 cups of coffee.

Finally, the World Cancer Research Fund and American Institute for Cancer Research recommends avoiding alcohol before and after a cancer diagnosis. If you do choose to drink alcohol, drink in moderation – that’s one drink per day for women and no more than two drinks per day for men. One drink is 12 oz. of beer, 5 oz. of wine, or 1.5 oz. of spirits. 

I’m having trouble eating…can what I drink help?

Absolutely! Some people, especially those with head and neck cancer, often only drink fluids throughout their treatment. It is possible to meet all of your nutrition needs this way, as long as you choose your fluids wisely. Smoothies and soups with added protein and nutrition supplement drinks can easily replace a meal or snack.

I’m having trouble even drinking – what should I do?

Most cancer centres have a registered dietitian who can help. Tell your care team about your difficulty with eating and drinking, and ask how to meet with the dietitian.

In the meantime, if you’re having trouble drinking because you don’t feel hungry, try taking small sips throughout the day and choose only high protein, high calorie fluids. Stir in protein or skim milk powder to add even more nutrition. Focus on fluids that you like, even if that means drinking milkshakes every day!

If fluids just don’t taste good, experiment with new flavours. Try soups with beans and lentils if meat tastes metallic. Add citrus, like lemon or orange, to smoothies to wake up your taste buds (unless you have mouth sores). If drinks taste too sweet, dilute with water or plain milk, or add a bit of salt.

If swallowing fluids is painful, avoid acidic and spicy flavours, drink fluids at room temperature, and puree and strain soups and smoothies to remove rough edges.

If the pain continues, speak to your doctor or a pharmacist. They may be able to prescribe a medication that can help.

About the author

Kelly Gillies-Podgorecki

Kelly is a registered dietitian at the Odette Cancer Centre.