FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

MICROWAVE COOKING DOESN'T CAUSE STOMACH PROBLEMS

Question: I know a number of people that are having stomach and intestinal problems. I suspect that this is caused by using microwave ovens. Do you think microwave ovens are safe?

Answer: Microwave ovens have become a standard fixture in most American kitchens. Despite their ubiquitous nature, many people don't understand the way they heat food. But to give you a short answer, microwave ovens are quite safe. In fact, they are responsible for many fewer injuries than conventional ovens.

Conventional ovens heat our food by raising the temperature of the air around it. Gas or electricity is used to heat the air within the oven, and then the hot air transfers heat to the food.

Microwave ovens heat our food using a totally different method. Electromagnetic energy, such as radio waves, comes in a variety of frequencies. It is the variation in these that allow us to have many radio and television stations. Obviously, these invisible radio waves carry energy that easily passes through the air, but not through large buildings or through the earth. In the case of a radio wave, the variation in its energy is amplified and converted into the sound we hear.

In microwave ovens the electromagnetic energy is typically generated at the frequency of 2450 megahertz(MHz), or 2450 million cycles per second, as compared to FM radio that uses frequencies from 88 to 108 MHz. When electromagnetic energy at this frequency strikes water, the molecules absorb the energy and become hotter in the process. The microwaves don't heat the air. Instead, they pass on through it as radio waves do. In other words, microwave ovens cook by selectively heating the water within the food. This, in no way, damages the food or makes it radioactive.

Since we humans are about 85 percent water, it is reasonable to question the health risks posed by exposure to microwave radiation. Many studies have been done to look into this question. The early ones were conducted by the government because microwave frequency radio waves are what makes radar work. The military application of very powerful microwave radar can cause harm to humans. Stepping in front of one of these is proportionally about like putting a mouse in your kitchen microwave. Poof! Boiled person or mouse. Actually, the heating of the water within our bodies, when within reasonable limits, poses no serious risk. In fact, there are medical devices that warm the blood of those who have hypothermia by passing it through a special, low-intensity microwave oven.

Individuals who are exposed to very large amounts of microwave radiation can sustain eye damage. This problem is seen most often in people who worked with early radar units and didn't obey safety regulations. The eye is particularly prone to microwave damage because it has less ability than other organs to remove excess heat.

Let me emphasize that I'm talking about really huge doses of microwave radiation to produce these eye problems. One almost needs to stand in front of an operating military radar antenna to get the necessary level of exposure. By contrast, all microwave ovens are designed to contain the much smaller amount of microwave energy they produce. In addition, all ovens have a safety device that automatically shuts off the microwave when the door is opened. The amount of microwave radiation that leaks out of an oven that is closed and operating poses absolutely no health risk.

Set aside your concerns. Microwave exposure doesn't cause stomach or other digestive troubles. The stomach and digestive problems experienced by many individuals definitely results from other causes.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.