Microwaves provide an energy-efficient way to heat food quickly and easily; however, they don't always heat food evenly and can potentially be harmful if food is not heated properly. Microwaves are useful for preparing convenient meals and for defrosting meats immediately before being transferred to the oven or grill.
According to The University of Texas Health Centers Northeast, carcinogenic compounds can potentially be released when cooking steak or hamburger in a pan or on the grill, but microwaving meats beforehand helps to prevent this.
Microwaves have their limitations. Only "microwave-safe" dishes should be used in the microwave; otherwise, unsafe chemicals like polyvinyl chloride may contaminate the food. According to foodsafety.gov, it’s important to follow directions on the boxes of convenient meals because it can be easy to undercook or unevenly cook the food in the microwave. Covering, stirring and rotating food may be necessary to ensure it is prepared safely. If these directions are ignored, the food may not be heated fully and bacteria will not be killed, causing food-borne illness. It’s important to also recognize that a microwave is not the same thing as a convection oven or a toaster oven.
The wattage of a microwave is also important — if the microwave’s wattage is lower than recommended, the food may not be heated entirely within the recommended time frame. If it is unclear whether a food has been heated properly, use a food thermometer to check the temperature.