Ketogenic Diet
Ketogenic diets are high in fat, moderate in protein, and low in carbohydrates, with weak to preliminary evidence of anticancer effects. A ketogenic diet can also improve body weight and insulin resistancea condition in which cells in your muscles, fat, and liver don’t respond well to insulin and can’t efficiently take up glucose from your blood for energy and support healthier blood sugar levels.
Ketogenic diet at a glance
The goal of a ketogenic diet (KD) is to decrease glucose and increase ketones to alter the metabolism of cancer cells and their associated stromal cells. KD has been studied primarily in malignant glioblastoma.
Ketogenic diets are medically regimented, high in fat, moderate in protein and low in carbohydrates. KD can be implemented either by restricting calories or by keeping the same number of total calories from your previous diet (isocaloric KD). Calorie restriction is considered an important component of an anticancer KD, as it supports your body’s retention of ketoneschemicals made in your liver to fuel metabolism; when your body doesn't have enough insulin to get energy from blood sugar, your liver turns fat into ketones and releases them into your bloodstream to fuel your brain, muscles and other tissues and also lowers cancer growth from extra calories or body weight.
Overall, evidence is weak to preliminary that a ketogenic diet has any anticancer effects or improves side effects of cancer treatment. Some evidence shows better blood sugar and insulin sensitivity among people with cancer (and strong evidence among people with diabetes), and also less inflammation among people following a ketogenic diet. Experts we reference do not recommend or use the KD much, and safety concerns are notable compared to the possible benefits.
CancerChoices ratings for ketogenic diet
We rate a ketogenic diet on seven attributes, with 0 the lowest rating and 5 the highest. We rate the strength of the evidence supporting the use of a ketogenic diet for a medical benefit, such as improving treatment outcomes or managing side effects.
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Improving treatment outcomes
See MorePeople with cancer eating a ketogenic diet have not been shown to live longer across many studies.
People with locally advanced breast cancer eating a ketogenic diet showed a greater response to chemotherapy in one study, but people with metastatic breast cancer did not show the same effect. In separate, poorly-designed studies, some people with advanced cancer eating a ketogenic diet had better outcomes; people with higher markers of ketosis were more likely than those with lower markers to have stable disease or remission.
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Optimizing your body terrain
See MorePeople with cancer eating a ketogenic diet had lower body weight and lower fat mass across many studies. Other studies found that people with cancer eating a ketogenic diet showed lower blood glucose levels but no changes in insulin levels.
People with diabetes or polycystic ovary syndrome (PCOS) eating a ketogenic diet had better blood sugar control and lower insulin resistance across many studies. In a study of people with PCOS, those eating a ketogenic diet had a greater reduction in two sex hormones—luteinizing hormone (LH) and dehydroepiandrosterone sulfate (DHEA-S).
People eating a ketogenic diet showed lower levels of triiodothyronine (T3), a thyroid hormone, in two small studies.
Eating a ketogenic diet did not show an effect on a marker of inflammation (TNF-α) among people with cancer across many studies. However, in one study, people with breast cancer eating a ketogenic diet had lower pro-inflammatory markers and higher anti-inflammatory markers during chemotherapy.
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Managing side effects and promoting wellness
See MorePeople with cancer eating a ketogenic diet showed a trend toward less loss of skeletal muscle or may even have gained a bit in two out of three studies. People with cancer eating a ketogenic diet showed better quality of life in three small studies and stable quality of life in another three.
For specific cancers, people with breast, ovarian, or endometrial cancer showed some evidence of better physical function in two studies. In one small study of people with breast cancer, those eating a ketogenic diet had better quality of life and/or better sleep quality during radiation therapy.
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Reducing cancer risk
See MorePeople with polycystic ovary syndrome eating a ketogenic diet showed fewer signs of fatty liver, a risk factor for liver cancer, in one small study. One very large combined analysis of studies found that people who ate plant-based low-carbohydrate diets had lower mortality from cancer, but people eating animal-based low-carbohydrate diets or low-carbohydrate diets as a whole had higher mortality from cancer.
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Use by integrative oncology experts
See More- Limited use by our program sources
- Not mentioned in oncology clinical practice guidelines
Safety
See More- Moderate caution is needed, and supervision by a medical professional is highly recommended
- Short-term side effects including nausea and vomiting, constipation, and heartburn are often seen early in implementation of this diet, and are usually transient and easily managed
- More severe and long-term side effects include weight loss, anemia, fatigue and more
- Preliminary evidencesignificant effects in small or poorly designed clinical studies OR conflicting results in adequate studies but a preponderance of evidence of an effect (this is the CancerChoices definition; other researchers and studies may define this differently) of low adherence and completion rates among people following a ketogenic diet; researchers interpret these as an indication that side effects or quality of life during KD are a barrier to participation or adherence
Affordability and access
See More- Widely available without restriction
- Somewhat expensive (between $500 US and $2000 US/year) if professional services and supervision are used as recommended
Keep reading about a ketogenic diet
Authors
Laura Pole is senior clinical consultant for CancerChoices. Laura is an oncology clinical nurse specialist who has been providing integrative oncology clinical care, navigation, consultation, and education services for over 40 years. She is the co-creator and co-coordinator of the Integrative Oncology Navigation Training at Smith Center for Healing and the Arts in Washington, DC. Laura also manages the “Media Watch Cancer News That You Can Use” listserv for Smith Center/Commonweal. In her role as a palliative care educator and consultant, Laura has served as statewide Respecting Choices Faculty for the Virginia POST (Physician Orders for Scope of Treatment) Collaborative as well as provided statewide professional education on palliative and end-of-life care for the Virginia Association for Hospices and Palliative Care.
For CancerChoices, Laura curates content and research, networks with clinical and organizational partners, brings awareness and education of integrative oncology at professional and patient conferences and programs, and translates research into information relevant to the patient experience as well as clinical practice.
Laura sees her work with CancerChoices as a perfect alignment of all her passions, knowledge and skills in integrative oncology care. She is honored to serve you.
Sophie received her Bachelor of Arts from the University of Cambridge, where she studied Middle Eastern languages and the philosophy of science. She then completed a premedical post-baccalaureate at the City University of New York. Before joining CancerChoices, she worked for several years at the Cornell Center for Research on End-of-Life Care, where she helped to conduct research on terminal illness and grief. Working in end-of-life research filled her with the conviction that all patients deserve free, accessible, and scientifically accurate information about the therapies available to them. While taking classes in anthropology, she also became curious about traditional medical knowledge and philosophies. These interests led her to CancerChoices. She is delighted to be part of CancerChoices’s work creating rigorous, evidence-based treatment guides for patients and physicians.
Ms. Hepp is a researcher and communicator who has been writing and editing educational content on varied health topics for more than 20 years. She serves as lead researcher and writer for CancerChoices and also served as the first program manager. Her graduate work in research and cognitive psychology, her master’s degree in instructional design, and her certificate in web design have all guided her in writing and presenting information for a wide variety of audiences and uses. Nancy’s service as faculty development coordinator in the Department of Family Medicine at Wright State University also provided experience in medical research, plus insights into medical education and medical care from the professional’s perspective.
Reviewer
Dr. Alschuler, ND, FABNO, is a professor of Clinical Medicine at the University of Arizona where she is the associate director of the Fellowship in Integrative Medicine at the Andrew Weil Center for Integrative Medicine. She received her undergraduate degree from Brown University and completed her naturopathic medical training at Bastyr University where she also completed her residency in general naturopathic medicine. She is board certified in naturopathic oncology and maintains a clinical practice out of Naturopathic Specialists, LLC. Dr. Alschuler co-hosts a podcast, Five To Thrive Live!. She is co-author of Definitive Guide to Cancer, now in its 3rd edition, and Definitive Guide to Thriving After Cancer.
Last update: January 30, 2025
Last full literature review: December 2024
CancerChoices provides information about integrative in cancer care, a patient-centered approach combining the best of conventional care, self care and evidence-informed complementary care in an integrated plan cancer care. We review complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocial therapy, and acupuncture therapies and self-care lifestyle actions and behaviors that may impact cancer outcomes; examples include eating health-promoting foods, limiting alcohol, increasing physical activity, and managing stress practices to help patients and professionals explore and integrate the best combination of conventionalthe cancer care offered by conventionally trained physicians and most hospitals; examples are chemotherapy, surgery, and radiotherapy and complementary therapies and practices for each person.
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