According to biology, sugar and fat can be transformed into each other. If you eat too much sugar, it will turn into fat if you don't digest it in time. Therefore, it is best to eat less sugar during weight loss.

Carbohydrates are polyhydroxy (two or more) aldehyde or ketone compounds, which can become organic compounds after hydrolysis. Chemically, because it is composed of carbon, hydrogen and oxygen, similar to the polymerization of carbon and water in the chemical formula, it is also called carbohydrate.

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Baidu encyclopedia-sugar