Alcohol suppresses pain and increases aggression, and the two effects are linked. In a new study, even small amounts of alcohol made people more tolerant of pain. That drop in pain sensitivity made them less caring toward others and more aggressive.
Summary: A recent study shows that drinking alcohol, even in small amounts, makes people more tolerant of pain. That makes them less caring toward others and more aggressive. So the aggression tied to drinking comes from lower pain sensitivity.
Alcohol is a mind-altering substance, and people drink it all over the world. Drunk responsibly, it is fairly safe. But alcohol addiction is not rare. For example, studies report that about 29 million adults are living with alcohol use disorder (AUD) in the US.
Heavy drinking is linked to many harms. It damages the liver, kidneys, brain cells and more. It also causes a shortage of certain nutrients. It greatly raises the risk of malnutrition.
A major concern is that alcohol changes the short-term and long-term behavior of people who drink often. For example, people who are drunk are more likely to act aggressively. Most people with AUD show aggressive behavior. Now a recent study shows this comes from lower pain sensitivity.
It has long been known that alcohol may dull pain. What is new in this study is that alcohol may have a long-term effect on the pain threshold. This dulled pain makes people with AUD less caring. They are more likely to ignore others’ feelings and act aggressively.
Alcohol slows down brain cells. So at higher doses, it changes what you feel, including pain. Long ago, alcohol was used to numb people for surgery. It is no longer used that way because the gap between a safe dose and a harmful one is very narrow.
It is vital to know that most of alcohol’s benefits come at very small doses. At higher doses, it is mostly harmful. Alcohol overdose can also kill. Alcohol causes both short-term and long-term harm. For example, being drunk can impair a person’s decisions and their movement. Over the long run, steady drinking may even change how the brain works.
For example, this study was done on people who did not necessarily have AUD. They were casual drinkers who had 3-4 alcoholic drinks a month. Even they showed changes in how their brains worked.
These were the results of two separate studies with 543 and 327 people. In both, people were split into two groups. One group got an alcoholic drink. The other got a placebo made to look like an alcoholic drink, with low alcohol content. Then both groups were exposed to something painful. The alcohol groups handled pain better and felt it less. Alcohol also made people more aggressive and more willing to put up with pain.
So researchers say this also makes people who drink less sensitive to the pain of others. People who do not drink can feel more pain. They would not want to cause pain to others.
Note that the people in the study had blood alcohol levels between 0.095% and 0.11%. That is just above the legal limit in most states, which is 0.08%. So even small amounts of alcohol can dull pain and make people more aggressive.
So it is logical to conclude that this effect would be even stronger in people who drink heavily and often. So, over time, people with AUD become more aggressive toward others. For those struggling with alcohol addiction and its effects, online alcohol addiction treatment offers a promising path to recovery and long-term health.
Source:
DeWall, C. N., Giancola, P. R., & Bushman, B. J. (2024). Too Insensitive to Care: Alcohol Increases Human Aggression by Increasing Pain Threshold. Journal of Studies on Alcohol and Drugs, jsad.24-00144. https://doi.org/10.15288/jsad.24-00144
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