Heavy drinking could disrupt people's body clocks. Researchers from Taipei Medical University studied some of the genes responsible for governing people's body clocks in a sample of 34 people, 22 of whom were alcoholics. The alcoholics had significantly less of a substance called messenger ribonucleic acid (mRNA) within their genes relating to their body clock. The reduced level of the substance in these genes did not return to normal once people had stopped drinking suggesting that heavy alcohol drinking could permanently upset people's body clocks.
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