Nutritional Supplementation May Interfere With Cancer Treatment

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According to Denise B. Reynolds, RD, patients eating well should not be experiencing nutritional deficiencies during cancer treatment.

In an interview with CancerNetwork® on nutrition during cancer treatment, Denise B. Reynolds, RD, discussed whether she observes deficiencies in vitamins or minerals among patients undergoing treatment for cancer, as well as her recommendations for supplementation.

Reynolds, a registered dietitian at Atrium Health Levine Cancer, suggested that patients who are eating well should not be experiencing any nutritional deficiencies while undergoing cancer treatment, except in unique cases. Those experiencing anemia whose red blood cells are breaking down may benefit from iron supplementation or infusion but should speak with a physician first. Additionally, vitamin D deficiencies may emerge, requiring supplementation.

Beyond potential iron and vitamin D supplementation, Reynolds recommends shying away from “high-powered” supplementation meant to boost the immune system, as these may interfere with chemotherapy or radiation.

Transcript:

It is different for every cancer, and cancer treatment is individualized. There are issues. For example, if you have nausea and vomiting, then you are [likely] losing a lot of fluid [and] you are not keeping the calories down. Overall, if someone is eating well, they should not be deficient in any specific vitamins. Now, the cancer treatment itself can cause anemia, because you are breaking down cells––breaking down red blood cells. A physician may ask that you take iron or may have an iron infusion. If you are deficient in vitamin D, which so many of us are, even without cancer, they might recommend a vitamin D supplement. Other than that, we do not recommend any supplements while you are receiving cancer care.

Certain supplements can be high in, say, antioxidants, and that can interfere with the chemotherapy [or] radiation. For [patients] who do not recognize that, they [may] have friends and family who give them high-powered supplements or drink something that helps boost their immune system, so to speak. We do not want that. That can interfere with some of the treatment that we offer our patients.

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