Myth: Consuming sugar causes breast cancer

By NBCF team

Last updated on Mar 3, 2026

Medically reviewed on Jan 31, 2026

by: Lillie D. Shockney, RN, BS, MAS, HON-ONN-CG

Here’s the truth

While sugar isn’t known for its health benefits, it does not cause breast cancer. Many doctors and health experts encourage patients to reduce or limit sugar intake because it is addictive and can contribute to mood swings, obesity, and illness. Weight gain and obesity, in particular, are risk factors in developing breast cancer and many other types of cancers; however, sugar itself does not make cancer develop or help tumors grow, as some myths hypothesize. Read more about sugar and breast cancer in the NBCF blog post, Does Sugar Feed Cancer?, written by a clinical registered dietitian.

Eating too much of any food can contribute to weight gain, obesity, and health issues, which can in turn increase breast cancer risk, but there is no direct link between sugar and breast cancer. Consuming sugar in moderation as part of a healthy diet does not cause breast cancer.

In a nutshell, it is never a bad idea to cut back on sugar consumption, but it shouldn’t be blamed for a breast cancer diagnosis. The best forms of sugar are the natural ones found in fruits, vegetables, and whole grains, since they also contain a variety of vitamins and minerals. It is recommended to avoid or reduce sugar in the form of sweetened drinks, desserts, and sauces and dressings, which often come with hidden sugars in the form of fructose, lactose, sucrose, maltose, or glucose.

Sources:
American Cancer Society
Dana-Farber Cancer Institute
WebMD