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Get My Top Nutrition Questions Answered


Find the answers to your top nutrition questions here.
Submit additional questions you may have and they may be featured in upcoming classes or videos!

Commonly Asked Questions

  •    Does sugar increase cancer risk?

    Sugar does not “feed” cancer. All carbohydrates break down into glucose, which is the fuel source for all cells in the body, not just cancer cells. For optimal health, try to limit added sugars, like those found in soda, candy, flavored yogurts, to less than 24 grams a day for women and less than 36 grams a day for men. Enjoy plenty of natural sugar sources, like fruits and vegetables!

  •    Does dairy increase cancer risk?

    For most types of cancer, dairy intake is not considered a major risk. Dairy intake likely protects against colorectal cancer. Aim for two or fewer servings a day of low-fat or fat-free dairy like plain yogurt or kefir.

  •    Does soy increase cancer risk?

    Soy is safe to eat, even for those with ER+ breast cancer. Soy intake has actually been linked to a lower risk of breast cancer, though exposure to soy earlier on in life results in the most protective effect.

  •    Are grilled foods safe to eat?

    Eating grilled food is not a major cause of cancer, but it does increase exposure to some chemicals that have been linked to cancer. Using lower fat cuts of meat, vinegar or lemon-based marinades, smaller cuts of meats like kebabs to reduce grill time, and balancing your meat with grilled vegetables can reduce the risk of exposure to these chemicals.

  •    How can I promote gut health after
       being on antibiotics?

    If tolerated, a high fiber diet can help to promote healthy gut bacteria after being on antibiotics. This includes a variety of fruits, vegetables, whole grains, nuts, and seeds. If increasing fiber, be sure to increase your intake slowly while simultaneously increasing your fluid intake.

    Naturally fermented foods that contain probiotics may also help to restore healthy gut bacteria. These include yogurt, kimchi, kefir, miso, and sauerkraut. Note: for those on Procarbazine (Matulane) it is important to limit fermented foods. Additionally, those who have gone through a stem cell transplant within the past year should avoid homemade fermented foods.

    Limiting ultra-processed foods to every once in a while may also support the gut microbiome. For more information on probiotics, check out our Zakim’s Kitchen presentation from November 2023.

  •    Does eating foods with small amounts
       of microplastics increase cancer risk?

    Some foods may contain microplastics due to environmental contamination from where the food is grown. However, there isn’t enough evidence to suggest that the microplastics migrate from food or beverage containers into foods. Per the Food and Drug Administration (FDA), the presence of environmentally derived plastics in foods does not indicate a health risk. The current evidence we have on microplastics from food increasing chronic disease risk is from lab studies done on animals. Therefore, it is difficult to understand the impact that microplastics in food have on human health. At this time, it is recommended to instead focus on the health benefits that can come from consuming whole, minimally processed foods like fruits, vegetables, whole grains, nuts, and beans, which have been associated with reducing chronic disease risk.