Alcohol and Brain Health: Even 'Moderate Drinking' Can Be Harmful

Can even moderate drinking — one or two beverages a day containing alcohol — be detrimental to your health? Yes, says a new report that gathered data from 83 studies in 19 countries, focusing on nearly 600,000 current drinkers.

Consuming more than 100 grams of alcohol — about seven standard glasses of wine or beer — per week was linked with an increased in risk of death for all causes, researches concluded. U.S. dietary guidelines recommend people who do not drink alcohol should not start. For adults who do drink, the guidelines suggest men have no more than two drinks per day and advise women who are not pregnant to drink only up to one drink per day.

The new report about moderate drinking, published recently in The Lancet, puts into question other studies that indicate a glass of red wine a day may be beneficial. The problem is that alcohol affects people differently, and other underlying health issues should be taken into consideration, healthcare professionals say.

“When people say ‘moderate drinking,’ what do they really mean?” says Sergio Jaramillo, M.D., neurologist with Baptist Health Neuroscience Center. “There are different concentrations of alcohol in different drinks. You should talk to your doctor about what a moderate amount of drinking is. There’s a lot of data out there that has to do with a glass of red wine a day.”

While there is some debate about the impact of one glass of wine or beer a day, there’s much more certainty about drinking too much. Excessive alcohol use led to approximately 88,000 deaths and 2.5 million years of potential life lost each year in the United States from 2006 to 2010, shortening the lives of those who died by an average of 30 years, according to the U.S. Centers for Disease Control and Prevention (CDC).

Regular excessive alcohol use is a known risk factor for liver disease, heart problems, diabetes complications, digestive problems, brain damage and a weakened immune system. Long-term excessive alcohol use has been linked to a higher risk of many cancers, including mouth, throat, liver, colon and breast. Even moderate drinking can increase the risk of breast cancer, studies show.

Alcohol and the Brain

Drinking even a glass or wine or beer a day, or hard liquor, can have a “calming effect” that eases social interactions, says Dr. Jaramillo. Alcohol also interacts with the brain’s neurotransmitter that sends chemical messages throughout the nervous system and is involved in regulating communication between brain cells. The role of this neurotransmitter, called gamma-aminobutyric acid or GABA, is to inhibit or reduce the activity of the neurons or nerve cells. In other words, GABA is primarily responsible for a person’s inhibitions.

“The more your drink, the more your brain gets used to being in that state,” says Dr. Jaramillo. “The problem is that it’s a very short-lived effect. If you want to continue that effect, you have to keep drinking. And the fact is that alcohol is very toxic to the body, including the brain and peripheral nerves. So there’s lots of evidence that clearly shows the bad effects of alcohol on the brain and nervous system.”

The brain’s GABA neurotransmitter plays an important role in behavior, cognition and the body’s response to stress. Prescription medications called benzodiazepines bind to the same receptors as GABA. They mimic GABA’s natural calming effects and that of alcohol. Diazepam (Valium) and lorazepam (Ativan), are among the most widely prescribed benzodiazepines for insomnia and anxiety disorders. They slow down the body’s central nervous system and cause sleepiness.

“There’s no doubt in my mind that there are people out there who use these chemicals for their own personal reasons to feel more comfortable at social gatherings,” says Dr. Jaramillo. “But then they have to go home and get in their car, and that’s another dangerous aspect for them and society in general.”

Binge Drinking and Blood Pressure

Binge drinking represents the most common “pattern of excessive alcohol use in the United States,” says the CDC. This typically happens when men consume five or more drinks, or women consume four or more drinks, in about two hours, the CDC states. Binge drinking can significantly raise a person’s blood pressure, the primary risk factor for stroke, says Ian Del Conde, M.D., a cardiovascular specialist at Miami Cardiac & Vascular Institute.

“Binge drinking is bad for our health — not only for the liver, which is probably the organ best known to be affected by alcohol, but also for blood pressure,” Dr. Del Conde said. “Large amounts of alcohol consumed in a short period of time, which is binge drinking, can elevate your blood pressure. So you can have a very high blood pressure on Saturday morning if you were binge drinking Friday evening. ”

Effects on Overall Health, Behavior

The researchers in the major recent study on moderate alcohol consumption also reported about seven to 14 drinks per week were associated with a heightened risk of heart disease, stroke, aortic aneurysm and heart failure. These risks were generally higher for the people who drank more, they concluded.

When it comes to the brain’s neurotransmitters, which normally contribute to a person’s good judgement, there is also evidence of a long-term impact from drinking alcohol, says Dr. Jaramillo.

“Alcohol can affect this part of the brain specifically,” he says. “People feel more comfortable and they tend to do things they would not normally do if they didn’t have alcohol in their bodies. Again, these effects are short term. But over time, there is also evidence of a long-term impact on this part of the brain which can change our behavior.”