Alberta Cancer Foundation

Expert Advice on Using Supplements Safely During Cancer Treatment

Illustration of Katie Keller by Jennifer Madole.



The body is hard at work during and after cancer treatment and can sometimes use a boost, nutrition-wise, in the form of supplements. Katie Keller is a registered dietitian at the Tom Baker Cancer Centre in Calgary and works to support the daily nutrition needs of cancer patients. Keller weighs in on the topic of supplementing for cancer patients.

Q: What are supplements?

Supplements can be a really big term for a dietitian. [Simply put], macronutrients are the big guys — think nutrients we get from our diet like protein, carbohydrates and fats — and a supplement that would give us something like that would be a protein powder or some type of meal replacement. Micronutrients are our little guys and [provide] vitamins and minerals. Some examples would be a vitamin C supplement or a B complex. A herbal supplement is typically an alternative treatment. It could be a concentrated form of blueberry extract or curcumin, which is the active ingredient in turmeric.

Q: Can eating a well-balanced diet eliminate the need for supplements?

Food really is the best way for us to get our nutrients. Supplements can be important and beneficial, but they’re not always [needed]. It depends on the individual and the type of situation presented. If people — including cancer patients on- or off-treatment — are eating a variety of different foods regularly throughout the day, they are most likely getting all the nutrients their body needs to function optimally, and this can help support their immune system.

Q: In what scenarios could supplements be helpful?

If someone is not able to get everything they need from their food — and this can be [in scenarios like] a pre-existing health condition, cancer side-effects/symptoms or a personal choice, like they’re vegetarian or vegan — it might be a situation where supplementing does become really important to support overall health and well-being. Within these situations, the type of supplements that we would suggest depends on the individual and their situation.

Q: When a patient is undergoing cancer treatment would you recommend they visit a nutritionist?

Yes, absolutely. Mostly we’re seeing patients because they’re not able to eat adequately — especially when they’re in treatment — and their nutrient needs can be elevated. If patients are losing weight, getting weaker, fatigued or maybe they’re having lots of food restrictions, then they would see us. Supplementing their diet might be an important part of their treatment. At the Tom Baker Cancer Centre, we see patients if they’re gearing up for surgery to do some nutrition optimization, but most commonly we see people who are actively on treatment.

Always check with your health-care team before using supplements during treatment.

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