Description
The Budwig diet consists of a special lacto-vegetarian regimen that focuses on a particular blend of oil and protein, i.e. flaxseed oil and cottage cheese or quark.
The general guidelines of the diet emphasise foods in their natural state, plenty of fat in the form of cold-pressed flaxseed oil and a spreadable fat based on flaxseed oil, and protein in the form of quark or cottage cheese. Freshly pressed juices and herbal teas are also an integral part.
Dr Johanna Budwig (1908-2003), a licensed pharmacist, stated that consuming processed fats was the primary cause of the majority of diseases, most notably cancer. According to her theory, combining polyunsaturated fatty acids derived from flaxseed with sulfhydryl-containing proteins from cottage cheese or quark has an effect on the growth and progression of malignant tumours.
Efficacy
Budwig recommended this diet for all kinds of diseases, and her approach is also said to have a preventive health effect in healthy people, especially eating flaxseed oil and quark on a regular basis. However, this theory is not borne out by current scientific evidence in the fields of nutrition research and cancer prevention.
No clinical trials of the Budwig diet are available in the peer-reviewed scientific literature to support these claims.
Safety
The safety of the Budwig diet has not been assessed. From the perspective of nutritional scientists, the main point of contention about the Budwig diet is that the protein and fat content are both well above the amounts recommended by medical Associations.
Description
The Budwig diet was developed in the 1950s by German chemist Johanna Budwig (1908-2003). At the core of the diet is a mixture of freshly ground flaxseed and low‑fat cottage cheese or quark. It is a largely vegetarian diet, emphasizing fruits, vegetables, whole grains, and nuts. Foods should be fresh, preferably organic, and eaten raw or only lightly cooked. The diet excludes refined sugars, meat, fish, hydrogenated and animal fats, alcohol, caffeine, refined grains, preservatives, processed foods, as well as smoking.
Background
The diet is based on a theory developed by Budwig about fats, proteins, and cellular oxygenation described in several of her books (Budwig 1996, Budwig 2000, Budwig 2008, Budwig 1994, Budwig 1994) some translated into English (Budwig 2008, Budwig 1994, Budwig 1994). The Johanna Budwig Foundation continues her legacy by raising public awareness of the importance of healthy fatty acids and emphasizing the role of a balanced and varied diet in maintaining health. (Budwig Stiftung 2026)
The Budwig diet is a lacto-vegetarian diet rich in complex carbohydrates, dietary fiber, vitamins, and phytochemicals. In some parts, it shares features with international recommendations for a balanced and varied (ovo-)lacto-vegetarian diet: its high nutrient and fiber content (and consequently the relatively low starch content) promotes satiety and may help reduce the risk of diet-related diseases (WCRF 2026; ACS 2026). However, compared with these recommendations, the Budwig diet has a substantially higher energy density due to its high flaxseed oil content.
Alleged indications
Budwig's theory postulates that cancers are caused, among others, by "inadequate cell maturation and incomplete cell growth" as well as "impaired cellular respiration." She also hypothesized that industrially processed fats and oils play a critical part in carcinogenesis. She claimed that the key element of her diet regimen, the special blend of the polyunsaturated fatty acids found in flaxseed and the sulfhydryl-containing proteins found in cottage cheese or quark, could re-establish normal cell growth and restore the normal function of damaged cells by "re-oxygenating" damaged tissues. (Budwig 2008, Budwig 1956)
Mechanism of action
According to Budwig’s hypothesis the enhancement of cellular oxygenation is the most important postulated mechanism. Budwig was influenced by Warburg’s hypothesis that cancer cells rely on low-oxygen (anaerobic) metabolism and proposed that a lack of proper fatty acids impaired cellular respiration and that the flaxseed oil with sulphur protein mixture restored oxygen uptake. (Budwig 2008, Budwig 1956) However, her theory is based on outdated fatty‑acid research. (Basch 2007).
Application and providers
The Johanna Budwig foundation trains naturopaths (“Heilpraktiker”, nutritionists, and physicians through webinars and seminars to become certified “Budwig advisors.” (Budwig Stiftung 2026)
No clinical trials or case reports about the effects of the Budwig diet on cancer prevention or treatment have been published in the scientific literature.
Plant-based foods contain only minimal amounts of Vitamin B12. An ovo-lacto-vegetarian diet includes eggs and cheese, two important sources of Vitamin B12, although these foods cannot meet a greater need. Since a vegetarian diet is rich in folates, the effects of Vitamin B12 deficiency can often be masked until neurological symptoms manifest (Craig 2010). For this reason, those who pursue a vegetarian diet or another kind of diet such as Budwig should make sure they take Vitamin B12 supplements to ensure an adequate supply (Vegan Society 2021).
Adverse events
The hull of flaxseed contains a mucilage that binds water in the intestines, expands and has a laxative effect. As a result, adequate hydration is necessary.
Flaxseed contains cyanogenic glycosides which can release hydrocyanic acid after hydrolysis in the intestine. When flaxseed is consumed in normal quantities, the resorbed quantity of hydrocyanic acid is not considered to pose a threat (Barthet 2010, Yang 2015).
Allergies to components found in flaxseed have been reported but are very rare (Fremont 2010).
Contraindications
Flaxseed is contraindicated in patients with ileus or stenoses in the gastrointestinal tract.
Interactions
Flaxseed can absorb orally administered medication and thus have an impact on its efficacy. Consequently, flaxseed (not flaxseed oil) should only be taken a few hours before or after taking medication by mouth to prevent decreased absorption (Basch 2007).
Warnings
Current knowledge indicates there is a positive correlation between the energy density of a diet and body weight. Medical societies recommend that weight-control measures take into account the protein content of the diet.
ACS, American Cancer Society. American Cancer Society Guideline for Diet and Physical Activity for Cancer Prevention | American Cancer Society [website]. 2026; accessed August 19, 2026.
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Basch E, Bent S, Collins J, Dacey C, Hammerness P, Harrison M, et al. Flax and flaxseed oil (Linum usitatissimum): a review by the Natural Standard Research Collaboration. J Soc Integr Oncol 2007;5(3):92-105.
Bechthold A. Food energy density and body weight. A scientific statement from the DGE. Ernahrungs Umschau 2014: 61(1): 2–11.
Budwig J. Cancer: The Problem and the Solution. Nexus GmbH; 2008.
Budwig J. Cytostatic or cytodynamic treatment of cancer. Hippokrates. 1956;19:605-12.
Budwig J. Das Fettsyndrom. Auflage 4A. Freiburg i. B.: Hyperion Verlag; 1996.
Budwig J. Flax oil as a true aid against arthritis, heart, infarction, cancer and other diseases. 3rd Edition. Vancouver: Apple Publishing; 1994.
Budwig J. Krebs, ein Fettproblem. Richtige Wahl und Verwendung der Fette. Freiburg i. B.: Hyperion Verlag; 2000.
Budwig J. The oil protein diet cookbook. Vancouver: Apple Publishing; 1994.
Budwig-videos.com [Website]. Available online, accessed 11th July 2023.
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Fremont S, Moneret-Vautrin DA, Franck P, Morisset M, Croizier A, Codreanu F, Kanny G. Prospective study of sensitization and food allergy to flaxseed in 1317 subjects. Eur Ann Allergy Clin Immunol. 2010;42(3):103-11.
Hales KH, Speckman SC, Kurrey NK, Hales DB: Uncovering molecular events associated with the chemosuppressive effects of flaxseed: a microarray analysis of the laying hen model of ovarian cancer. BMC Genomics 2014; 15:709.
The National Center for Complementary and Integrative Health. Omega-3 Fatty Acids: What the Science Says [online document].
Vegan Society: What Every Vegan Should Know About Vitamin B12. Available online, accessed 11 July 2023.
World Cancer Research Fund International. Our Cancer Prevention Recommendations as a package of behaviours | World Cancer Research Fund [website], 2026; accessed August 19, 2026.
Yang QY, Song L, Zhang JF, Shen ZF, Liu Q, Liu SN, Zheng WS, Yao CS. Cyanogenetic glycosides and simple glycosides from the linseed meal.Fitoterapia. 2015 Oct;106:78-83.
Citation
Mora D, Wider B, CAM Cancer Collaboration. Budwig diet [online document], Jul 31, 2023
Document history
Assessed as up to date in July 2023 by Dana Mora. Revised in May 2021, August 2020, January 2019 and February 2017 by Barbara Wider. Fully revised and updated in January 2016 by Markus Horneber. Assessed as up to date in January 2015 and August 2013 by Barbara Wider. Summary first published in May 2012 by Luc Geeraert. Next update due: July, 2026
Photo: mp37860777 from Mostphotos.com, licence via UiT The Arctic University of Norway.
