The principle of microwave heating is that the friction and vibration between molecules in food are caused by microwave radiation to generate heat, just like the friction between two hands to generate heat. The friction between molecules is called internal friction, which produces more than 3000 oscillations per second, and the heat of microwave oven comes from here.
Therefore, microwave heating is only physical heating, which itself makes food hot from the inside out, but it will not cause chemical changes in food, so it will not produce so-called carcinogens.
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Correct use of microwave oven
1. Before using the microwave oven, you should check whether the appliances used are suitable for the microwave oven.
2. Before cooking, put away the turntable bracket and the glass turntable, and then put the food on the turntable for cooking.
When cooking a small amount of food in the microwave oven, pay more attention to fire prevention, and don't store any food in the microwave oven.
When food is heated in a simple container made of plastic, paper or other materials, you should always pay attention to prevent fire.
5. When the oven door is damaged by collision or falling, don't continue to use it. Professional maintenance is required before use.
Reference source; People's Daily Online-Food Safety Expert: Microwave heating food will not cause cancer.