Heavy Drinking May Affect Men's Brains More than Women's, Study Says

It might be time to stop cracking open a cold one with the boys, as new research suggests that men may be more affected by heavy drinking than women. In fact, male hard-drinking habits might have a greater impact on an important neurotransmitter that helps moderate anxiety and depression.

Scientists were already aware that heavy alcohol use can have an effect on the brain over time, especially if heavy drinking begins in adolescence while the brain is still developing. But a group of Finnish researchers studying the brains of young adults with a history of heavy drinking assumed that women would be more affected by their liquid habits than men. In fact, it’s turned out to be the reverse.

“We found more changes in brain electrical activity in male subjects, than in females, which was a surprise, as we expected it would be the other way around,” says Dr. Outi Kaarre of the University of Eastern Finland and Kuopio University Hospital. “This means that male brain electrical functioning is changed more than female brains by long-term alcohol use”

The work was presented Sunday at the ECNP Congress in Paris, Europe’s premier scientific meeting for disease-oriented brain research.

The researchers studied the brains of 11 young men and 16 young women with heavy, 10-year histories of alcohol use, and compared them with the brains of 12 young men and 13 young women who didn’t really drink. All study participants were between the ages of 23 and 28.

By recording participants’ brain responses to magnetic stimuli — known as Transcranial Magnetic Stimulation (TMS) — they observed that the men who drank showed a greater increase in electrical activity in the brain in response to TMS than women who drank, specifically regarding GABA (gamma-amino butyric acid) neurotransmission.

While there are two types of GABA receptors (A and B), researchers found that long-term alcohol use affected neurotransmission in both types in males, but only affected GABA-A in females. GABA neurotransmission is responsible for reducing excitability in the nervous system; it calms down brain activity and is important in regulating anxiety and depression.

According to Kaarre, the results might mean that sex assigned at birth could be a factor when planning pharmacological treatment for alcoholism. The researchers also noted that the relationship between sex hormones and neurotransmission ought to be studied further.