Alcohol might shrink the brain, cause dementia

Alcohol consumption, even in small amounts, might shrink brain size in the long run, according to a recent study.

The study, conducted at Boston University, tested 1,839 people age 33-88. It shows that there is about a 1.5 percent difference between the total brain volume of heavy alcohol drinkers and abstainers. What it does not address, however, is the effect this shrinkage actually has on brain function.

Experts at USF said the reported difference in size is not very significant and stressed that function is not always correlated with brain size.

“The amount of shrinkage reported is equal to less than a year of life,” said James Mortimer, Ph.D., a professor and researcher in the College of Public Health. “It is not clear whether or not people were worse off cognitively.”

The study is still an important find, however, because it sheds new light on the effects of drinking alcohol in small amounts.

“This is the first time that anyone really demonstrated that so-called casual drinking has an effect on brain size,” Mortimer said.

Research shows that the brain shrinks with age — slowly at first, but more rapidly at older ages. When the brain shrinks in certain areas, it can cause diseases that impair brain function.

“Alzheimer’s disease is the major cause of brain atrophy in old age,” Mortimer said.

Dementia, caused by a rapid loss of brain cells, starts in the hippocampus region of the brain, said Ross Andel, a professor in the School of Aging Studies.  From there, he said, it spreads to other parts of the brain and affects memory and other brain functions.

Alcohol can have positive and negative effects on brain function. Both Mortimer and Andel said it depends on how much a person drinks. College students who binge drink take the least healthy track by drinking large quantities of alcohol in a small amount of time.

“Alcohol carries a toxin that makes brain cells more vulnerable,” Andel said.

Brain cells must strengthen themselves to fight against alcohol in small amounts, Andel said. With large doses of alcohol, however, the cells become too vulnerable and die easily. Alcohol also dehydrates the brain and body.

“People who are alcoholics have a considerable amount of brain shrinkage,” Mortimer said.

Though the study shows that people with histories of light or moderate drinking — 1-2 drinks per day — have smaller brains, many other studies show that they are actually more healthy than those who abstain or drink heavily, Andel said.

“(Moderate drinking) may shrink the brain, but it makes it work well,” he said.

Alcohol, in small amounts, is known to prevent Alzheimer’s disease and dementia, Mortimer said.

It also helps prevent heart disease, Andel said, and increases good cholesterol levels while breaking down bad cholesterol.

College students may be worse off if they start drinking large amounts of alcohol at a young age, Mortimer said, because they can develop habits that could last their whole lives.

“Those that drink in a high-risk manner pose a risk to themselves and others,” said Assistant Director of Health Promotion Holly Rayko Murphy.

Students at USF can learn about alcohol through first-year University Experience classes, the peer education program Responsible Education and Action for Campus Health, and an online program called AlcoholEdu, she said.

This is the second year USF has used AlcoholEdu to educate students before they come to college. If students don’t finish the course, they are reported to the Office of Student Rights and Responsibilities.

Though it is difficult to measure the effectiveness of these programs, Murphy said they help.

Tom Conlon, a junior engineering major, said he does not drink, and though he was not educated about drinking when he came to USF, he still learned about it.

“In small doses, it helps your heart and maybe puts you in a better mood if you had a rough day, but in excess it is bad for you,” he said.

Conlon said the new evidence about alcohol might not affect society much.

“It probably wouldn’t change the way people drink,” he said. “People would do it anyway.”