Study "officially" ties drinking alcohol to unsafe sex

(CBS) It's official. A new study ties drinking alcohol to unsafe sex.

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It's no secret that boozing and bad decisions go hand-in-hand, but scientists had yet to determine a cause-and-effect relationship when it comes to drinking and unsafe sex - until now.

For the study, published in the Jan. issue of Addiction, researchers conducted 12 experiments to put the theory to the test. The scientists found that drinking alcohol affects decision-making, and, spoiler alert: the more alcohol one drinks, the more impaired the decision-making. For every 0.1mg/mL increase in blood alcohol level, study participants were 5 percent more likely to engage in unsafe sex.

The finding may not sound earth-shattering to some, but the authors say their study suggests that drinking alcohol should be considered a major risk factor for sexually transmitted diseases.

"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", study author Dr. Jurgen Rehm, director of social and epidemiological research at the Centre for Addiction and Mental Health in Ontario, said in a written statement. "This result also helps explain why people at risk often show this behavior despite better knowledge: alcohol is influencing their decision processes."