It can be reused, but there is definitely no new oil that is good for the body. If it is repeated too many times, it will produce substances that are bad for the body. Re-frying oil is cooking oil that is heated repeatedly for secondary use, including salad oil and commonly used cooking oil. Refrigerating oil will produce a large amount of harmful substances and cause great harm to the human body.

According to inspections from relevant departments, after repeated heating of edible oil, it will accelerate the oxidation process and produce many harmful substances. In fact, after repeated frying of food or adding new oil to repeatedly used oil, this kind of oil is also a kind of gutter oil in a broad sense, which is extremely harmful. Repeated heating of oil at high temperatures will produce toxic and harmful substances. Because polymers, dimers and trimers are produced by unsaturated fatty acids in oil after repeated high-temperature heating, they are highly toxic.

After repeated use and high-temperature heating of frying oil, a series of chemical reactions will occur, such as increased viscosity, increased foaming, darker color, worse flavor, increased oil smoke, etc., thus reducing the quality of the oil. . Not only that, but it also has the potential to cause cancer. Eating fried foods often causes indigestion, chest tightness, and even nausea, vomiting and diarrhea. Loss of appetite, etc.

According to relevant research, many human diseases, such as tumors and vascular sclerosis, are related to the oxidation of oil. In particular, "returned oil" contains a large amount of trans fatty acids, which if consumed for a long time, can lead to obesity. , diabetes, cardiovascular and cerebrovascular diseases and other diseases; heating edible oil contains carcinogens such as benzopyrene, which can cause lung cancer if inhaled for a long time. Experts believe that oil will undergo chemical reactions under high temperature for a long time and can produce toxic components. Some of the deteriorated oil has carcinogenic effects and is as harmful as "gutter oil".