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Soy Fiber in Powder Formula

Ask the Nutritionist

Q: Can I use USDA soy fiber to help stay regular after treatment? I am using a soluble and insoluble fiber powder form that has flaxseed and oat bran as major components.

G. Promades, Barrington, Rhode Island 

A: Whole soybeans and soy foods are a common plant source that are also a complete protein, which means it has all of the essential amino acid building blocks for protein that the body needs from food, just like animal proteins such as meat and chicken. Over a third of the calories in soybeans come from its protein content. Flaxseed is great to consume ground because it provides a "healthy fat" in addition to fiber.

Processed soy like soy protein or fiber powders are not recommended for patients with a history of estrogen positive cancers, like breast, uterine, and ovarian cancer.

It’s important to pay special attention when buying soy protein or fiber powders that they do not contain any GMOs. GMOs are organisms that have been genetically modified by genetic engineering. An example is taking a component from the arctic flounder that has properties like anti-freeze and splicing them into a tomato to prevent damage from frost.

Why are GMOs a big concern? They are not natural so we do not know the individual effects on people that ingest them. Not all protein or fiber powders contain this but you want to read the label closely to be sure.

To help with constipation post-treatment, consuming fruits, vegetables, whole grains and other plant-based foods along with adequate hydration can be very effective, healthy and safe. Check out our recipes in the Dana-Farber nutrition app. You can search by symptoms such as constipation.

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  • Ask the Nutritionist

    • Do you have questions about making healthy food choices during and after cancer treatment? Our team of nutrition experts can help. Submit your question through our Ask the Nutritionist form.
    • To create a customized plan, please schedule an appointment with a Dana-Farber nutritionist by calling 617-632-3006.
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