Myth: I can change my body’s pH by eating certain foods.

Answer: Busted!

Some fad diets claim that you can make the pH of your body less acidic (in other words, more alkaline) by consuming more fruits, vegetables, and milk and less meat, fish, eggs and grains. This diet is based on some studies showing that cancer cells growing in test tubes will grow faster in an acidic environment and some anti-cancer drugs work better in an alkaline environment. Supporters of the diet argue that your urine, and therefore your body as a whole, will become more alkaline by following this diet. They believe that the more alkaline your body is, the better it can protect itself against cancer.

Unfortunately, there are several major flaws in the alkaline diet theory. First, following an “alkaline diet” will make your urine more alkaline, but it doesn’t change your blood pH. Urine is contained in the bladder and is not the same as blood. The kidneys are constantly working to keep blood pH from ever changing significantly; a condition that can make a person extremely sick and even result in death if untreated. Additionally, numerous studies show that no human cells can survive in an alkaline environment, regardless of whether they are healthy cells or cancer cells.

Eating a diet rich in fruits and vegetables is a good way to help prevent cancer because of the many nutrients that fruits and vegetables contain. Don’t be fooled into cutting out other food groups, especially whole grains and heart-healthy fish, which can also protect against some cancers.

Contributor: Mary Wissmann, MS, RD, LD, Nutrition and Health Education Specialist, St. Louis County, University of Missouri Extension, WissmannM@missouri.edu