Less oil is mainly to reduce fat intake. The human body's ability to use fat as energy is very limited, and the fat eaten is likely to be stored. Needless to say, the consequences of too much fat. As for eating salt, it is mainly because eating salt will increase the ion concentration in the human body. In order to adjust the ion concentration of blood, the human body will dilute it by drinking too much water. However, after these extra saline enter the blood, the blood volume will increase, which will lead to high blood pressure.
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