Alkaline vs. Acidic Foods and Cancer

It's confusing that mainstream medicine debunks the alkaline diet as quackery while advocating a very similar diet to help prevent cancer and other diseases. In an essay posted on the Quackwatch website, Dr. Gabe Mirkin writes that if someone informs you that your body is too acidic, "you would be wise not to believe anything else the person tells you." However, if the same person tells you that in order to stay healthy and protect yourself against disease, you should eat more plant foods and limit your consumption of animal products -- the fundamental basis of the alkaline diet -- most doctors would call it excellent advice.

ALKALINE DIET

The theoretical basis of the alkaline diet, also known as the acid alkaline diet and the alkaline ash diet, is that after foods are digested, they leave an "ash" that can be acidic, alkaline or neutral, depending on mineral content. Overconsumption of foods such as meat and dairy products promote an acidic pH balance in the body that can lead to serious degenerative conditions, including cancer and heart disease. Conversely, the alkaline ash created by eating mostly plant foods consists of minerals essential to sustaining health and fighting disease. The ideal ratio between the food groups is 80 percent alkaline to 20 percent acidic, proponents of the alkaline diet say.

MAINSTREAM POSITION

Dr. Mirkin calls the acid-alkaline theory of disease "nonsense," but reserves his sharpest criticism for promoters of products such as coral calcium and alkaline water. As for changing the pH balance of the body with dietary modifications, it can't be done, he says. Strong stomach acids render all food acidic until it moves into the intestinal tract, where secretions from the pancreas neutralize it into alkalinity. The claim that cancer cells can't survive in alkaline liquid is true -- "but neither can any of the other cells in your body," Dr. Mirkin writes. Only the pH balance of urine, not blood, changes with diet, he maintains.

MIXED MESSAGES

In their eagerness to discredit the alkaline diet, medical watchdog groups like Quackwatch sometimes appear to be contradicting the dietary recommendations of both mainstream experts and the American Dietetic Association. According to the American Institute for Cancer Research, scientific evidence suggests that a predominantly plant-based diet indeed confers protection against some forms of cancer. The institute advises that for a healthy diet, at least two-thirds should consist of fruits, vegetables, whole grains and legumes. This position is shared by the World Cancer Research Fund, the American Cancer Society and the Canadian Cancer Society. Even though proponents of the alkaline diet advocate a similarly balanced diet, the Canadian Cancer Society maintains that no evidence exists to support the effectiveness of the alkaline diet.

MODERATE POSITION

In an essay posted on the website of Brigham and Women's Hospital, a teaching affiliate of Harvard Medical School, clinical nutritionist Stephanie Vangsness takes a more moderate stance, not discounting the possibility that the alkaline diet might yet be shown to have value. It's true that no human studies have been done to support or refute the role that diet may play in preventing or treating cancer, she writes, but test tube and animal studies have shown that some cancer cells multiply faster in an acidic environment, and some chemotherapy drugs work better in an alkaline environment.