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

A 2014 review "did not find clinical evidence supporting” its use in cancer patients.⁵

Block and Gyllenhaal caution that long-term use of this diet may result in inadequate protein and omega-3 fatty acid intake.⁶

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.⁷  

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.⁸

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.”⁹ 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.”¹⁰ 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.¹¹

• 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 causes¹³ or with lower risk of incident, sporadic colorectal adenomas.¹⁴ 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.¹⁶

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.¹⁷
• A 2018 review found no beneficial effect of a vegetarian/vegan diet on breast cancer recurrence.¹⁸
• A vegan diet's elimination of dairy foods may confer benefit in some types of cancer, such as prostate cancer¹⁹   and non-Hodgkin lymphoma.²⁰ However, dairy foods may be protective against colorectal cancer.²¹ Consistent with this, a large study in 2016 found that vegan diets are associate with reduced prostate cancer risk,.²²
• 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.²³

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