Teenage girls who binge-drink have a higher risk of long-term harm to the brain compared to boys of the same age who also binge drink, researchers from the University of California, San Diego and Stanford University reported in Alcoholism: Clinical and Experimental Research.

Their definition of binge-drinking is consuming at least four (for females) or five (for males) alcoholic drinks at one sitting.

The investigators said that activity levels in several regions of the brain among girls who binge drink were lower than what one would normally find among typical teenagers.

Co-author, Susan Tapert, from Stanford University, said:

“These differences in brain activity were linked to worse performance on other measures of attention and working memory ability.”

Although changes in brain activity levels were observed among teenage boys who binge drink, they were less severe than what was observed in the girls.

The authors warned that teenage girls are particularly vulnerable to the harmful effects of alcohol abuse.

There could be many reasons why the girls’ brains are more affected, including:

  • A girl’s brain tends to develop a couple of years earlier than a boy’s.
  • A girl has a slower metabolic rate than a boy
  • There is usually a higher body-fat ratio in a girl than a boy
  • Girls generally weigh less than boys
  • Boys and girls have hormonal differences

The authors added that what they found among teenage male and females was similar to studies on adults who abuse alcohol – women tend to be more vulnerable to its harmful effects on the brain.

Of the 95 teenagers who participated in this study, 40 said they had taken part in sessions of binge drinking.

The researchers asked them how often they had consumed an alcoholic drink during their lifetime, and also what their alcohol consumption had been during the three months before the study began.

The boys and girls were asked to carry out tasks which activated brain parts responsible for spatial working memory, while at the same time being scanned with an MRI (medical resonance imaging) device.

Impaired spacial memory can lead to several problems in daily living, including driving a vehicle, using a map, remembering how to get somewhere, taking part in certain sports, and figural reasoning.

The researchers stressed that none of their 95 participants was alcoholic or had a drink problem. Any binge-drinking session was done socially, and subsequent drinking of alcohol did not occur again for several weeks.

However, Edith Sullivan, from Stanford University School of Medicine, said that the harmful effects of drinking too much persisted for a long time after the event.

Sullivan said:

“Long after a young person – middle school to college – enjoys recovery from a hang-over, this study shows that risk to cognitive and brain functions endures.”

According to the authors, nearly 30% of all teenagers in America in their last year of school reported binge drinking during the previous four weeks. Data from the CDC (Centers for Disease Control and Prevention) shows that approximately 75% of alcohol consumed in the USA (all ages) is done so during binge-drinking sessions.

Written by Christian Nordqvist