Microwave ovens were created for heating food items in the late 1940s, but they didn't become popular until the 1960s. Microwave ovens (or microwaves for short) can be found in most households in the United States because of their convenience for heating food efficiently and quickly. The microwave is approved for use by the Food and Drug Administration (FDA), but there are natural health practitioners who believe that the appliance is not safe for cooking food. Also, while a microwave can do many things, it cannot cook everything as well as an oven or stove.
Items You Cannot Cook
Microwaves can be used to cook many safe plastic containers, but there are some items that microwaves may melt or spark a fire. Metal items are never approved for use in a microwave. When metal is cooked in a microwave, it functions as an antenna for electrical current in the device and can lead to fire and explosion. Some items that contain metal are metal twist ties, metal pans, Chinese take-out containers, China with metallic trim or paint, and aluminium foil. Other various containers that can cause a microwave malfunction include brown paper bags, cottage cheese tubs, foam insulated cups or bowls and newspapers.
Burnout and Superheating
The phenomenon known as burnout occurs when a microwave is set to cook with no food in the oven or if a dehydrated food is cooked. Burnout is when the magnetron tube of the microwave literally cooks itself and the poisonous beryllium is released after breaking. Superheating occurs when an object is heated above its boiling point and disturbed in such a way that it explodes. This can happen with closed water containers and closed containers with eggs. When these items are disturbed after cooking, they may erupt and burn the user.
Loss of Nutrients
A study at Osaka Prefecture University in 1998 showed that cooking pork, beef and milk in a microwave oven lowered the amount of vitamin B12 by 30 to 40 per cent. A study by Cornell University showed that microwaving spinach reduced the nutrient folate by a negligible amount compared to cooking it on the stove (77 per cent loss). These studies show that microwaves can reduce nutritional content but not necessarily more or less than other methods of cooking. When cooking vegetables in a microwave it is best not to place them in water as it may cause much larger reduction in nutrients than when vegetables are not put in water.
Theories on Negative Effects
In the 1970s in Russia, the microwave was banned after a post World War II report that stated microwaves led to many possible health problems. Natural health practitioners who believe the microwave is dangerous point to this study and speculate that the device can lead to increased disease and a stronger chance of cancer. They point to success stories of individuals who stopped using microwaves and improved their health, but there are few if any scientific studies that prove increased illness from a microwave or reduced illness from not using a microwave.