Can Grapefruit Raise Your Risk of Breast Cancer?

There has been some conflicting information published over the years regarding grapefruit, specifically as it relates to the risk of breast cancer. Some studies have shown a reduced risk of breast cancer, while others have shown the opposite.

This article will review the information currently available about grapefruit and breast cancer risk.

Fresh grapefruit on chopping board
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Studies on Grapefruit and Breast Cancer Risk

A study published in 2007 looked specifically at the link between breast cancer development and grapefruit intake in a group of 50,000 postmenopausal women, and found that there is potentially a correlation between grapefruit intake and breast cancer. In that study, there was a 30% increase risk of breast cancer in women who at at least a fourth of a grapefruit per day.

In contrast, a different study done in 2008 did not find the same results, showing no difference in breast cancer rates in women who ate grapefruit regularly.

How Grapefruit Affects the Body

Grapefruit and grapefruit juice contain certain enzymes that can affect how the liver processes some medications. This altered process can lead to higher or lower levels of medications in the body. Considering this action, some research has shown that grapefruit may similarly lead to elevated estrogen levels in the body.

Grapefruit May Raise Estrogen Levels

A 2013 study showed the effect grapefruit had on estrogen levels in a woman's body when it was eaten regularly. It was found that postmenopausal woman who ate more grapefruit had higher estrogen levels. Further studies are needed on women who are premenopausal, with naturally higher levels of estrogen.

Grapefruit can also have an effect on the way medications used to treat breast cancer are absorbed by the body. The enzyme pathway, which grapefruit affects, can cause the liver (which is responsible for metabolizing many medications) to cause too much or too little of the medication to work.

Nutritional Value of Grapefruit

When thinking of the possibility that grapefruit could have an effect on postmenopausal breast cancer risk, it's important to weigh this against the potential benefits of adding grapefruit to a healthy diet. Grapefruit is rich in vitamin C as well as phytonutrients.

In studies of people who ate or drank grapefruit products regularly, they had better cholesterol levels, an overall healthier diet, and healthier body weight.


There have been multiple studies that have shown the benefits of eating grapefruit or drinking grapefruit juice regularly. Although there are many people that can possibly benefit from this, there are people who should avoid grapefruit, as it can interfere with their medications or potentially increase their risk of getting breast cancer. If you ever wonder if you should or should not be eating grapefruit, talk to your healthcare team.

Frequently Asked Questions

  • How does grapefruit affect estrogen?

    The enzyme pathways in the body can be affected by grapefruit. Some of these pathways can interfere with other enzymes in the body, and can lead to an increase in estrogen levels.

  • Should breast cancer patients avoid grapefruit?

    If a patient living with breast cancer is taking any medication to treat their breast cancer, they should discuss whether or not they can eat or drink grapefruit products with their cancer care team first.

  • What medications should not be taken with grapefruit?

    Grapefruit has interactions with many medications. Some of these medications include blood pressure medications, cholesterol medication, anti-depressants, steroids, cardiac medications, plus others.

  • Can you eat grapefruit when taking tamoxifen?

    Grapefruit should not be eaten when taking tamoxifen, as the grapefruit changes how the medication is processed in the body. This makes the tamoxifen less effective in treating breast cancer.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Monroe KR, Murphy SP, Kolonel LN, Pike MC. Prospective study of grapefruit intake and risk of breast cancer in postmenopausal women: the Multiethnic Cohort StudyBr J Cancer. 2007;97(3):440-445.

  2. Kim EH, Hankinson SE, Eliassen AH, Willett WC. A prospective study of grapefruit and grapefruit juice intake and breast cancer riskBr J Cancer. 2008;98(1):240-241.

  3. Mayo Clinic Proceedings. Drug-Grapefruit Juice Interactions.

  4. Murphy MM, Barraj LM, Rampersaud GC. Consumption of grapefruit is associated with higher nutrient intakes and diet quality among adults, and more favorable anthropometrics in women, NHANES 2003–2008. Food Nutr Res. 2014;58:10.3402/fnr.v58.22179.

  5. U.S. Food and Drug Administration. Grapefruit Juice and Some Drugs Don't Mix.

  6. Nolvadex Prescribing Information. Food and Drug Administration.

Additional Reading

By Julie Scott, MSN, ANP-BC, AOCNP
Julie is an Adult Nurse Practitioner with oncology certification and a healthcare freelance writer with an interest in educating patients and the healthcare community.

Originally written by Pam Stephan
Pam Stephan is a breast cancer survivor.
Learn about our editorial process