These findings are based on twelve separate studies compiled by researchers at the Centre for Addiction and Mental Health in Toronto. In many of the studies, participants were randomly designated to a drinking group or a sober group. Their willingness to have unsafe sex was then measured. A boost in one's blood alcohol level of 0.1 mg/mL, increased the likelihood of having sex without a condom by 5%. For most Americans, this amounts to around four drinks for women and five for men.
“Drinking has a causal effect on the likelihood to engage in unsafe sex, and thus should be included as a major factor in preventive efforts for HIV,” said Dr. J. Rehm, the lead investigator of the study. “This result also helps explain why people at risk often show this behavior despite better knowledge: alcohol is influencing their decision processes.”
Furthermore, programs designed to reduce overpopulation and unplanned pregnancies should also address the role alcohol plays in unprotected sex.
The full study, "Alcohol Consumption and the Intention to Engage in Unprotected Sex: Systematic Review and Meta-Analysis of Experimental Studies," is published in the journal Addiction.
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