Cancer diets are often in the news. However, they may not be based on scientific evidence, which means gathered through a very strict process. All of PearlPoint’s diet and nutrition recommendations are based on evidence supported by the Academy of Nutrition and Dietetics and generally accepted by the medical/oncology community.

The diets described below, while receiving a lot of publicity, have not been tested through clinical trials. PearlPoint Cancer Support does not advise the use of any of these diets.

Gerson Therapy

Gerson Therapy is a diet program that people have used instead of traditional medical treatment. Dr. Max Gerson developed the diet in the 1930s as a self-prescribed treatment for his migraine headaches. Later, supporters of the Gerson Therapy claimed the therapy treated many diseases, including cancer.

Gerson Therapy attempts to strengthen the body’s immune system through special diets, supplements, and other methods that are believed to remove toxins from the body. Gerson Therapy is a very strict program that lasts over two to three years.

While some aspects of the therapy such as fresh fruits and vegetables, low-fat choices, and low sodium intake can be healthy, this therapy can lead to malnutrition when taken to the extreme. Coffee enemas are a very dangerous part of Gerson Therapy. Coffee enemas can cause severe adverse reactions. Serious illness and death are attributed to other features of this treatment as well, such as liver cell injections and restricted intake (leading to nutritional deficiencies).

The studies cited and conducted by Gerson supporters do not follow the recommended guidelines for clinical trials. The studies used flawed patient selection criteria, and many participants dropped out, leading to unreliable information. There is no sound evidence that Gerson Therapy is a safe or effective treatment for cancer. Oncologists do not recommend Gerson Therapy as a treatment for cancer.

Macrobiotic Diet

The macrobiotic diet is often a vegetarian diet that includes whole grains, cereals, fruits, and cooked vegetables. The fruits and vegetables are supposed to be locally grown. Items to avoid include: eggs, dairy items, coffee, refined sugar, red meat, poultry, and processed foods. Cooking methods and utensils are limited. All food is supposed to be chewed very well. Macrobiotic diet excludes vitamins and supplements. Supporters of the macrobiotic diet claim that the diet can prevent and cure disease, including cancer.

As with the Gerson Therapy, there are no clinical trials in medical publications to support the claim that the macrobiotic diet prevents or cures cancer. The earliest macrobiotic diet consisted of only brown rice and water. The early diet led to frequent malnutrition and death. Current macrobiotic diet guidelines that allow for more flexibility still lack key nutrients and enough calories.

Many cancer survivors struggle to maintain proper nutrition from side effects during cancer treatment, which often leads to malnutrition and involuntary weight loss. The macrobiotic diet can increase these risks in cancer survivors.

The macrobiotic diet is not safe or effective for cancer survivors. Oncologists do not recommend the macrobiotic diet during or in place of cancer treatment.

Fasting and Juicing

Fasting and juicing often occur together. There are two types of fasting: traditional and dry fasting. Traditional fasting avoids all food but does allow fluids (juices and water). Juicing can be the source of those fluids. Dry fasting avoids all food and fluids Fasting usually lasts for 24 to 48 hours or, in some extreme cases, longer.

Juicing is very popular among cancer survivors and the general public. Juicing involves drinking the juice from fruits and vegetables instead of eating them. Juicing can be included in a healthy lifestyle as a way to work more fruits and vegetables into meals and snacks, but juicing alone can be dangerous. Since juice is low in fiber, protein, and many other non-plant nutrients, it is not an adequate source of nutritionand it does not improve the immune system.

Supporters of fasting and juicing believe the practice cleanses the body of toxins to improve overall health. In reality, toxins still remain in the body even after fasting. Fasting can lead to loss of valuable nutrients and a decline in the immune system. Frequent juicing can provide a dangerous level of antioxidants, which may interfere with some cancer treatments.

There are no large scientific studies of fasting and juicing that prove they prevent or treat cancer. The imbalance of nutrients, calories, and fluids in long-term fasting can place a cancer survivor at risk for malnutrition, low blood sugar, dehydration, and loss of lean muscle mass.

Fasting is not safe during cancer treatment. Juicing may be used as a way to add extra fruits and vegetables to meals, but it should not be used as the only source of nutrition.

What Does Work

If you are faced with a cancer diagnosis, your nutrition can be an important part of your journey. Eating a well-balanced diet before, during, and after cancer treatment can help you feel better, maintain your strength, and speed your recovery.

How do I make the best food choices throughout my cancer treatment?

  • Maintain a healthy weight.
  • Eat small, frequent meals throughout the day.
  • Choose foods that are high in protein.
  • Include whole grain foods for more energy.
  • Eat a variety of fruits and vegetables every day.
  • Eat healthy fats from plant-based sources.
  • Limit sweets and added sugars.
  • Drink liquids often to stay hydrated.
  • Practice good food safety.
  • Drink alcohol in moderation, if at all.
  • Talk to your healthcare team before taking any vitamins or supplements.
  • Most importantly, know that your cancer journey is unique to you and your treatment. PearlPoint is here to guide you – contact us today.

For more tips, check out our article: "I Have Cancer. What Should I Eat?"