image from scientificamerican.com
Microwave ovens are appliances that dominate almost every kitchen in the United States. Since their increasing household use in the 1980s there were rumors of risk from microwaves. The Think Twice Blog exists because the momentum of such “myths” can carry them for decades after they are proved false. To this day, as we reheat our leftovers in a microwave, we may stop to think twice about whether the convenience of a quickly heated meal is worth the potential risk of exposure to microwave radiation. Afterall, the sun can cause cancer due to ultraviolet (UV) radiation, and we have probably all heard not to stand too close to microwaves at some point in our lives. But do you actually have to worry about developing cancer from microwave radiation?
Radiation is used to heat up our food. However, the radiation emitted by microwaves is low-energy. On the other hand, UV radiation is high-energy and can damage DNA in our cells. DNA damage can lead to cancer, which is why we protect ourselves using protective sunscreen. In contrast, microwave ovens only have enough energy to vibrate the water molecules in our food. This movement of water molecules creates the water vapor that heats and cooks our food, similar to how we generate heat when our hands rub together. The Minnesota Department of Health states irradiated energy passes through the food like”light through a window” which is also why food heated in a microwave is not radioactive after it is heated.
The potential harms of microwave radiation are minimal. Microwaves are very closely regulated to prevent high levels of radiation leakage through provisions such as safety locks to prevent the oven from operating when the door is open. The FDA allows 5 milliwatts per square centimeter of microwave radiation leakage two inches away from the microwave or farther, which is far below the level known to be harmful to humans. While we can decrease our exposure to microwaves by standing further from the device while it’s on, the waves emitted from this device are not dangerous to humans at any distance.
Keep in mind that if your microwave is damaged in any way, it is best to not use it. However, in most cases, we can enjoy the convenience of microwaves without fear. No, the convenience of microwaves is not too good to be true. Enjoy those wonderful reheated seconds!