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At this frequency it will not show any bad effect on liver
.Alcohol when enters the body and reaches liver , it effects liver cells and depending on the concentration of alcohol levels in blood liver cells die. But once left without any influence liver can grow.So at that frequency even a few number cells die , they ll grow back.
The main problem is people start with at low frequency and get addicted to it .With addiction the frequency increases.
So do not worry as of now , but let him not get addicted to it.