Description
The Breuss Cancer Cure is based on a strict dietary regimen involving a 42‑day fast combined with specific vegetable juices and herbal teas. Additional recommendations include avoidance of so‑called “water veins.” The approach is based on Breuss’ hypothesis that cancer cells depend on solid food for survival.
Efficacy
Claims of efficacy are not supported by evidence from clinical trials. There are no reliable scientific data to substantiate either the therapeutic effectiveness of the treatment or its proposed mechanism of action.
Safety
The prolonged fasting regimen may pose significant risks for cancer patients, particularly due to the likelihood of malnutrition. Furthermore, because Breuss discouraged the use of conventional cancer treatments during the regim
Description and Background
Description and background
The Breuss Cancer Cure is based on a strict 42‑day fast combined with specific vegetable juices and herbal teas. Additional recommendations include avoiding so‑called “water veins.”
Rudolf Breuss (1899–1990), an Austrian electrician turned naturopath, developed this regimen, which he described in Cancer – Leukemia and Other Apparently Incurable Diseases (first published 1978; later editions 1990) (Breuss 1990). Further editions have appeared since his death, including a revised version in 2022 (Breuss 2022). Translations exist in multiple languages; the first English version appeared in 1995, with an updated edition in 2019 (Breuss 1995, Breuss 2019). The extent to which later editors altered the original text remains unclear; for instance, the English version omits his prohibition of radiotherapy and injections (Breuss 1995). Additional guidance was provided by Thomar (Thomar 2008/2014; Mit der Breuss Kur 2001).
Despite widespread translation (Breuss 1990, Breuss 1995), data on prevalence are lacking. Patient testimonials are available online (Mit der Breuss Kur 2001; Healing Cancer Naturally 2001; Kroiss‑Cancer‑Center 2021), and some spa facilities offer Breuss fasting (Vita Natura Klinik 2021; Stilles Haus 2021).
Alleged Indications
Breuss claimed to have treated over 2,000 patients since 1950 and estimated that an additional 40,000 patients with cancer or other “incurable diseases” were cured using his method. Evidence consisted mainly of testimonials and thank‑you letters (Breuss 1990, Breuss 1995; Moerman 2004). He argued that failures resulted from non‑adherence and believed up to one million people could be cured if conventional medicine supported his approach (Breuss 1990).
Applications and Dosage
Patients are instructed to consume only prescribed juices and teas for 42 days. Daily juice intake (maximum 500 ml) includes beetroot, carrot, celeriac, and black radish; potatoes are added for liver cancer. Ingredients should be organic and filtered.
Three core teas are recommended:
- Sage tea (Salvia officinalis, Hypericum perforatum, Mentha piperita, Melissa officinalis), taken freely
- Kidney tea (e.g., Equisetum arvense, Urtica dioica, Polygonum aviculare, Hypericum perforatum), limited to the first three weeks
- Cranesbill tea (Geranium robertianum), restricted to half a cup daily
Additional teas are suggested for specific cancers, and sugar is prohibited. For leukemia, patients may eat other foods, excluding meat soup, pork, beef, reheated foods, and (in the English version) certain additives and fats (Breuss 1990; Breuss 1995; Moerman 2004).
Breuss advised delaying the regimen for 2–5 months after surgery and avoiding concurrent therapies. Exercise, fresh air, and smoking cessation were encouraged, along with avoidance of environmental exposures such as insecticides or “water veins.” After the fast, patients should gradually reintroduce light, low‑salt foods and continue small amounts of juice (Breuss 1990, Breuss 1995).
Later additions include onion broth, hawthorn tincture for cardiac support, and continued insulin use in diabetics (Breuss 1990, Breuss 1995). Further recommendations included herbal mixtures for mineral supplementation and alternative broths for liver or gallbladder conditions (Breuss 1990).
Mechanism of Action
Breuss proposed that cancer cells depend on solid food and cannot survive on vegetable juices, thus dying during the 42‑day regimen (Breuss 1990, Breuss 1995; Moerman 2004). He cited claims that tumors rely on protein intake and suggested that a protein‑free diet enables the body to destroy tumors “like surgery without a knife.” He claimed that his diet could not only cure but also prevent cancer.
Although caloric restriction can reduce tumour incidence and growth in some contexts (Berrigan 2002; Leary 2002; Cleary 2007; Thompson 2002), effects vary by tumour type (Kalaany 2009). In contrast, starvation (fasting) is a form of malnutrition and has not shown therapeutic benefit; in some cases, tumour growth may increase during acute fasting (Tomasi 1999; Goodgame 1979; Hikita 1999; Sauer 1986; Tessitore 1996).
Legal Issues
The juices used in the regimen are commercially produced (e.g., Biotta Inc.) and widely available in health food shops, pharmacies, and online (Biotta 2023).
A review of cancer diets which included the Breuss Cancer Cure did not identify any clinical evidence. No clinical trials have been published in the peer-reviewed literature and only a description of eight cases is available (Douwes 1984).
Anticancer treatment
Only one small uncontrolled study including eight cancer patients with metastatic diseases has investigated the “Breuss Cancer Cure” (Douwes 1984). The authors reported two complete, and two partial remissions. Furthermore, they state that patients felt better than expected during the intervention and experienced less pain. During the trial, one patient died and two died shortly after completion of the trial. The authors did not attribute the deaths to the intervention. No further studies have been published (Huebner 2014). The case reports found on the Internet (Mit der Breuss Kur 2001, Healing Cancer Naturally 2023, Kroiss-Cancer-Center 2023), lack valid documentation.
Published evidence on the safety of the Breuss cancer treatment is not available.
Adverse Events
Senn and Jungi reported that the Breuss cure led to rapid and clinically significant cachexia in several patients (Senn 1979). Similarly, Douwes et al. observed substantial weight loss ranging from 9 to 16 kg (Douwes 1984). Such findings indicate a high risk of severe malnutrition associated with the regimen.
Malnutrition is well known to adversely affect cancer patients, contributing to increased morbidity and mortality, prolonged hospitalisation, and reduced quality of life (Inui 2002; Zürcher 2002; Maltoni 2005). Based on these concerns, the Schweizerische Gesellschaft für Onkologie and the Schweizerische Krebsliga reviewed the Breuss cure, cited the findings of Senn and Jungi, and advised against its use (Schweizer 1982; Krebskur 1987).
Interactions
No published data are available on potential interactions.
Contraindications
No published data are available on contraindications.
Warnings
Breuss explicitly rejected conventional cancer treatments during the regimen. As a result, patients may forgo evidence‑based therapies with proven benefit, potentially compromising clinical outcomes.
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Citation
CAM Cancer Collaboration. Breuss Cancer Cure [online document], May 18, 2026.
Document history
Assessed as up to date and revised in May 2026, January 2023, May 2021, August 2020, January 2019, February 2017, January 2016, January 2015 and August 2013 by Barbara Wider. Updated in by March 2012, January 2011 and October 2009 by Karl Krumwiede. Summary first published in November 2005, authored by Karl Krumwiede and Markus Horneber. Next update due: May 2029.
Photos: Mostphotos.com
