Alternative and Popular Cancer Diets

For example, Anthony Sattilaro, MD, diagnosed with metastatic prostate cancer, figured he had nothing to lose and adopted the macrobiotic diet. He experienced complete resolution of his bone lesions at one and four years after diagnosis. His and other similar stories were published in popular media, creating great interest among cancer patients.

Whole grains make up the bulk of the diet, then vegetables, then beans and sea vegetables, then vegetable soups. Other foods such as nuts, seeds, fruits and fish are eaten occasionally. Dairy, red meat and sugar are all absent. Macrobiotic dietary counselors will advise patients to adapt the diet based on the season, the climate, and personal and other factors.

A 2001 review concluded: “The role of the macrobiotic diet in cancer prevention and survival has not been investigated adequately to justify scientifically the recommendation that macrobiotics be used in the context of cancer. However, the lack of studies that examine directly the effects of macrobiotics on cancer prevention, survival or quality of life cannot be taken as evidence against a beneficial effect of macrobiotics. In particular, there is extensive indirect evidence that macrobiotic dietary patterns are associated with reduced cancer risk as well as the potentially reassuring results of the few studies that evaluated directly the effects of the macrobiotic diet on estrogen metabolism and cardiovascular risk.”²

A 2014 review reported that experts evaluating six case reports “did not find a proof of a positive impact of the diet in any case.”³

In sum:

• Evidence supporting the use of this diet for cancer risk reduction, survival or quality of life is lacking.
• Scientific proof is a very high standard and difficult to achieve. Indirect evidence suggests that this diet is associated with lower cancer risk.
• Lack of evidence in this case could indicate that more research is needed and not that the diet is ineffective.

This diet involves particular preparation requirements that are often quite involved and labor-intensive, which could be a problem if no one with sufficient energy or time is available to prepare this diet.

Block and Gyllenhaal caution that difficulty with this diet can “arise for patients with cachexia [body wasting and weakness] due to the low caloric density of this diet.”⁴

• Lerner M. Macrobiotics—A Diet and a Way of Life, in Choices In Healing: Integrating the Best of Conventional and Complementary Approaches to Cancer
• Kushi LH, Cunningham JE et al. The macrobiotic diet in cancer. Journal of Nutrition. 2001 Nov;131(11 Suppl):3056S-64S.
• CAM-Cancer: Macrobiotic diet
• Cancer Research UK: Macrobiotic diet
• Susan G. Komen: Macrobiotic Diet

NCI’s PDQ states that “The data that are available are not sufficient to warrant claims that the Gerson therapy is effective as an adjuvant to other cancer therapies or as a cure.”⁶ In his 1994 book, Michael Lerner predicted that controlled clinical trials of the regimen would likely find a small but significantly increased number of cures, along with a wide range of increase in life expectancy and improved quality of life.⁷ A 2014 review of evidence to that point, including a National Cancer Institute expert panel review, did not find convincing evidence of benefit.⁸

Block and Gyllenhaal state that the Gerson regimen can be rigorous and difficult to follow. They emphasize that monitoring the patient with cachexia for adequate protein intake is important, and caution that fruit juice intake may compromise blood sugar control.⁹

• Lerner M. The Gerson Diet—A Radical Anticancer Therapy, in Choices In Healing: Integrating the Best of Conventional and Complementary Approaches to Cancer
• National Cancer Institute: Gerson Therapy (PDQ®)—Health Professional Version
• Memorial Sloan Kettering Cancer Center: Gerson Regimen
• Moss Reports (purchase required): description of the Gerson regimen as well as a description and evaluation of several clinics offering the Gerson Regimen

The full regimen also includes pancreatic enzymes, a host of supplements (about 130 capsules per day), fasting, colonic irrigation and coffee enemas. It is a variant of the Kelley Method developed by dentist William Kelley, also borrowing from the Gerson Regimen. Like the Gerson regimen, the Gonzalez one can be rigorous and difficult to follow. The number of supplements alone can be a challenge for some patients. However, BCCT staff have known patients who claim to have been helped by the Gonzalez Regimen.

Pilot Study

According to Linda Isaacs, MD, colleague of Dr. Gonzalez, at the urging of the associate director of the National Cancer Institute, she and Dr. Gonzalez pursued a pilot study of their methods in ten patients suffering inoperable pancreatic cancer. “The study was completed and the results were published in the June 1999 issue of Nutrition and Cancer.¹¹ Of 11 patients followed in the trial, eight suffered stage 4 disease, the most advanced stage. Results:

• Nine of 11 (81 percent) lived one year or longer
• Five of 11 (45 percent) lived two years or longer 
• Four of 11 (36 percent) lived three years or longer
• Two (18 percent) lived longer than four years

In comparison, in a trial of the drug gemcitabine studying 126 patients with pancreatic cancer, not a single patient lived longer than 19 months.¹²

Clinical Trial

The encouraging results of this pilot study were the impetus for the National Cancer Institute and the National Center for Complementary and Alternative Medicine to approve funding for a large-scale clinical trial. That controlled trial involved patients with advanced pancreatic cancer who were allowed to choose treatment with either the chemotherapy drug gemcitabine (control group) or an enzyme treatment including orally ingested proteolytic enzymes, nutritional supplements, detoxification and an organic diet (experimental group). “The median survival in the experimental group was 4.3 months, in the control group 14 months. The quality of life ratings were significantly better in the chemotherapy group compared to the enzyme-treated group.”¹³

The clinical trial results seem to be bad news for those following the Gonzalez Regimen. However, Isaacs explains, “Unfortunately, the study was ineptly managed by the academicians involved, who were used to studies involving drugs, not lifestyle changes, and many if not most of the patients assigned to the nutritional protocol did not comply with their treatment.”¹⁴

Isaacs points out that the researchers flooded the Gonzalez Regimen arm of the study with patients who were not actually doing the protocol. The researchers did not mention this in their research publication. Dr. Isaacs says that “like so many other studies in alternative medicine, because of flaws in design and execution this study failed to answer the questions it was meant to address.” See Dr. Gonzalez' book What Went Wrong or Dr. Isaac’s article Research Battles¹⁵  for further information.

2019 Case Study

Two patients, one with colon cancer metastatic to the liver and lung and another with lung cancer with brain metastasis, followed an enzyme-based nutritional protocol using diet, supplements and detoxification methods of the Gonzalez program. Both patients experienced "prolongation of life and resolution of radiographically apparent disease."¹⁶ The author points out that "case reports cannot be considered as proof of efficacy, these cases added to others of patients treated with the same method would suggest that this is a viable option for those patients whose disease cannot be treated successfully with other modalities.."¹⁷  

For a description of individualized nutritional protocols following the Gonzalez Regimen, see Dr. Linda Isaacs—Individualized Nutritional Protocols.

• National Cancer Institute. Gonzalez Regimen (PDQ®)–Health Professional Version
• Isaacs LL. Pancreatic Proteolytic Enzymes and Cancer: New Support for an Old Theory. Integr Cancer Ther. 2022 Jan-Dec;21:15347354221096077.

A 2014 review "did not find clinical evidence supporting” its use in cancer patients.¹⁸

Block and Gyllenhaal caution that long-term use of this diet may result in inadequate protein and omega-3 fatty acid intake.¹⁹

A 2014 review concluded that raw foods can be irritating or difficult to tolerate in patients with chemotherapy-induced mucositis or stoma, and may incur a higher risk of gastrointestinal infections.²⁰  

BCCT senior scientist Laura Pole, RN, MSN, who is also a health-supportive chef, and chef Rebecca Katz, MS, caution that some raw foods may be difficult to digest and cause any number of gastrointestinal discomforts as well as feeling cold, particularly when eaten in cold climes and seasons. At the Hippocrates Institute in Florida, a raw-foods diet is more in tune with the seasonal foods available there than it might be in other climates. Furthermore, some foods need to be cooked in order for the body to digest and absorb their nutrients—for example dark leafy greens such as kale. Mushrooms should be eaten only if cooked to neutralize naturally occurring toxins.²¹

According to the American Institute for Cancer Research (AICR), “The unsubstantiated theory is based on lab studies that suggest cancer cells thrive in an acidic (low pH) environment, but cannot survive in alkaline (high pH) surroundings. . . While these findings are accurate, they apply only to cells in an isolated lab setting. Altering the cell environment of the human body to create a less acidic, less cancer-friendly environment is virtually impossible.”²² AICR advises: “What you eat can have a profound effect on your cancer risk, but the acidity or alkalinity of foods is not important. Instead, focus on making dietary choices that can truly affect your risk: Eat a wide variety of vegetables, fruits, whole grains and beans; limit consumption of red and processed meats; enjoy alcohol in moderation, if at all.”

Naturopathic oncologist Neil McKinney, ND, states: “An alkalizing diet is good for cancer patients. . . but why it works well has very little to do with pH. Extreme pH therapies are not recommended.”²³ Thus eating these types of foods can be beneficial, even though the theoretical basis of the diet is questioned.

However, some credible integrative oncology clinicians say there may be some validity to this diet. According to naturopathic oncologist Lise Alschuler, ND, FABNO, acidosis is associated with impaired immunity, reduced glutathione and reduced insulin sensitivity. She points to growing evidence that reducing acidosis may provide benefits and that an alkaline diet doesn’t need to be extreme to be helpful.²⁴

• WebMD: Alkaline Diets
• American Institute for Cancer Research: Alkaline diets

As with the Mediterranean diet, higher adherence to the Paleolithic diet is associated with lower mortality either from cancer or from all causes²⁶ or with lower risk of incident, sporadic colorectal adenomas.²⁷ Mortality benefits were slightly greater from the Mediterranean diet.

In conclusion, the Paleolithic diet shares characteristics with other healthy diets, but strict adherence may eliminate food groups proven to be beneficial for cancer prevention and general health.

• Mayo Clinic: Paleo diet: What is it and why is it so popular?
• WebMD: The Paleo Diet
• Scientific American: How to Really Eat Like a Hunter-Gatherer: Why the Paleo Diet Is Half-Baked

A meta-analysis found an estimated 15 percent reduced incidence of total cancer from following a vegan diet.²⁹

Whether avoiding all animal products is necessary for obtaining the positive health benefits of a vegan diet is not clear.

• Vegans, vegetarians, and fish-eaters all showed reduced risk for all cancers compared to non-vegetarians in a large European study.³⁰
• A 2018 review found no beneficial effect of a vegetarian/vegan diet on breast cancer recurrence.³¹
• A vegan diet's elimination of dairy foods may confer benefit in some types of cancer, such as prostate cancer³²   and non-Hodgkin lymphoma.³³ However, dairy foods may be protective against colorectal cancer.³⁴ Consistent with this, a large study in 2016 found that vegan diets are associate with reduced prostate cancer risk,.³⁵
• Colorectal cancer incidence in a large prospective cohort study was lowest in those who ate a vegetable-based diet with the addition of seafood, while vegans and vegetarians had lower and similar reduced risk compared with non-vegetarians.³⁶

A vegan diet eliminates natural food sources of vitamin B₁₂, essential for the body to produce red blood cells and prevent anemia. Either supplements or foods fortified with vitamin B₁₂ are needed to prevent a deficiency that can lead to serious health problems.

Calcium from milk products is also missing from a vegan diet but can be addressed by vegetable foods rich in calcium:

• Dark green vegetables including turnip and collard greens, kale and broccoli eaten in sufficient quantities
• Calcium-enriched and fortified juices, cereals, soy milk, soy yogurt and tofu

• Mayo Clinic: Vegetarian diet: How to get the best nutrition
• The Atlantic: The Evidence for a Vegan Diet
• HealthLine: The Vegan Diet—A Complete Guide for Beginners