So, really how bad are microwaves for us?
Since the advent of the home microwave in 1955, fear of exposure to radiation has been a consumer concern. For people with heart arrhythmias, early models of pacemakers were adversely affected by closeness to microwave ovens. However, the level of radiation emitted from modern home microwaves is considered too low to pose any health risk. While important to working mothers in enabling fast preparation of meals for their children, and an anchor to fast-food retailers—some food items should not be cooked in a microwave.
How Microwave Ovens Work
Cooking in a microwave oven occurs through exposure to microwave radiation (a form of electromagnetic energy)—which causes the water molecules of the food to rotate, resulting in a temperature increase. Inside the oven, the microwaves are actually produced by an electron tube (called a magnetron). The Food and Drug Administration in the United States is charged with national oversight of standards of performance in accordance with public health safety laws. Federal regulations limit the amount of microwaves that may “leak” from a microwave oven to 5mW of microwave radiation per square cm over its lifetime. Various websites and articles that I have found emphasize damage to the eyes (e.g., cataracts) and reproductive organs. Spontaneous miscarriages are a risk for pregnant women who work intensively with microwave ovens during their first trimester (per an article in the Observer college newspaper). In general, pregnant women need to be careful when using microwave ovens.
Microwave Risk to Restaurant Workers
The amount of radiation exposure from industrial microwave ovens to restaurant workers far exceeds that of people using microwaves at home. Therefore, there is a health risk for restaurant workers who spend a high number of hours working in close proximity to them—as well as for those restaurant employees working with aging or malfunctioning microwave ovens. Since “fast-food” retail establishments usually employee youthful staff, microwave risk is also increased due to the potential for burn accidents from over-heating foods.
Advantages and Disadvantages to Our Diet when Cooking with Microwave Ovens
Higher moisture losses occur in microwave cooking as compared to conventional methods. As a result, nutrients in vegetables can leach out into the cooking water (according to the Harvard Medical School Family Health Guide). However, an article in Critical Reviews in Food Science and Nutrition—entitled, “The Effect of Microwaves on Nutrient Value of Food”—suggested only slight differences in nutritional quality between food cooked in microwaves and conventional methods.
Overall, don't stand in front of the microwave when you are cooking and try to keep your microwave up to date; if it is 10 years older or more, I would replace it.