02/23/2012 10:52 am ET Updated Apr 24, 2012

Alcohol Can Lead to Unsafe Sex

It will come as no surprise that drinking lots of alcohol can go hand-in-hand with bad decision making. But up until recently, scientists had yet to come up with a direct cause and effect relationship regarding alcohol and unprotected sex.

In the January issue of the journal Addiction, a new study reported that researchers in Canada conducted 12 experiments to test the theory. The results -- yes, rather obvious --confirmed that drinking alcohol affects decision-making, and the more alcohol one drinks, the more impaired the decision making. As the results show, for every 0.1mg/mL increase in blood alcohol level, study participants were five percent more likely to engage in unsafe sex.

While the findings may not seem overly-newsworthy, they do confirm the direct connection between alcohol and sexually transmitted diseases. The study's conclusion states that "alcohol use is an independent risk factor for intentions to engage in unprotected sex, and as risky sex intentions have been shown to be linked to actual risk behavior, the role of alcohol consumption in the transmission of HIV and other STDs may be of public health importance."

"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 principal investigator Jürgen Rehm of the Centre for Addiction and Mental Health in Toronto, in a press release. "This result also helps explain why people at risk often show this behavior despite better knowledge: alcohol is influencing their decision processes."