Even moderate amounts of alcohol can alter teens' brain and liver function, possibly leading to higher alcohol tolerance later in life, according to new research from Baylor University.

For the study, researchers raised the blood-alcohol content of young male rats to between .05 and .09 percent through alcohol administration simulating low-dose binge drinking. They found that these rats exhibited higher tolerance for alcohol than a control group when exposed to alcohol again after several years of abstinence.

"Many people balance their alcohol consumption based on perceived changes in their behavior, and what we show is that you can have no changes in your behavior in terms of tolerance but still be changing liver and brain function that will produce tolerance later in life," said lead researcher Douglas Matthews. "The body and brain are still developing during adolescence and this shows even a small amount of alcohol can have harmful effects."

The study findings were published online Nov. 28, 2008 in the journal Alcohol.