Tuesday, 16 April, 2024
HomeHarm ReductionCutting back, quitting alcohol, may reverse brain shrinkage: US study

Cutting back, quitting alcohol, may reverse brain shrinkage: US study

A study by American researchers has suggested that quitting or cutting back on drinking can improve brain health, and that people who reduced their alcohol consumption to a low-risk level had less brain shrinkage.

Published in Alcohol: Clinical and Experimental Research, the paper indicates that for people with alcohol use disorder (AUD), even reducing the amount they drink can be helpful when it comes to brain health.

The National Institute on Alcohol Abuse and Alcoholism described AUD as a brain disorder characterised by an inability to stop or control alcohol consumption, even though it negatively affects relationships, health or work life.

The Stanford University-led study found that when people with alcohol use disorder either reduced their intake or quit drinking completely, they had greater volume in particular regions of the brain than people who drank more heavily.

Additionally, reports Healthline, when they returned to a low-risk level of drinking – no more than three drinks per day for men or 1.5 drinks for women – the volume of these brain regions more closely resembled that of people who did not drink at all.

The authors suggest that, given the difficulty of quitting entirely, cutting back alcohol consumption may be a more doable goal for some than complete abstinence.

Can brain cells grow back after alcohol use?

To conduct their study, the researchers collected data from 68 people aged 28 to 70 with AUD.

The participants were matched with a control group of 34 people of a similar age who were either non-drinkers or light drinkers.

To judge the health of their brains, the team used magnetic resonance imaging (MRI) to compare the cortex volume in various regions of their brains.

They looked at those who entered treatment and either stopped drinking; resumed drinking, but at low-risk levels; or resumed drinking at higher-risk levels.

About eight months after they started treatment, the higher-risk drinkers had significantly less volume in 12 out of 13 regions when compared with the controls.

Low risk drinkers had less volume in nine of the 13 regions.

People who did not drink at all had less volume in six of the 13 regions.

The researchers further found that higher-risk drinkers had less volume than non-drinkers in four specific frontal regions as well as the fusiform and precentral cortical regions.

Low risk drinkers, on the other hand, had significant differences from non-drinkers in the precentral and rostral middle frontal cortex.

The authors note that the brain’s frontal regions play several important roles, including decision-making, emotional regulation, and working memory. Less volume in these regions could make people less able to perform these functions.

What does alcohol do to your brain over time? 

Dr Daniel Atkinson, GP clinical lead at Treated.com, explained that although research doesn’t show that drinking could destroy brain cells, it could lead to shrinkage.

This particular study, he noted, showed that even moderate alcohol consumption could cause the hippocampus, which was associated with learning and memory, to reduce in size over time.

“This could be, in part, because the hippocampus is an area of the brain with a unique and delicate structure,” he said, “where new neurons are constantly being created through neurogenesis.”

According to Atkinson, previous studies have shown that high levels of alcohol consumption could interfere with this process.

Long-term alcohol use might also cause shrinkage because alcohol is a diuretic and causes water to be removed from the body.

“If this water isn’t adequately replaced, it can cause dehydration,” he said.

“This effect would be mostly seen across the whole brain though,” he added, “whereas this study shows hippocampus shrinkage most predominantly, suggesting that neurogenesis inhibition plays a bigger role in the reduction of brain size.”

Study details

Non-abstinent recovery in alcohol use disorder is associated with greater regional cortical volumes than heavy drinking

C. May, DJ Meyerhoff, TC Durazzo

Published in Alcohol Clinical & Experimental Research on 14 October 2023


Harm-reduction (i.e., non-abstinent recovery) approaches to substance use treatment have garnered increasing attention. Reduced levels of alcohol consumption post-treatment have been associated with better psychosocial functioning and physical health, yet less is known regarding differences in brain structures associated with varying levels of alcohol consumption. This study investigated regional cortical volumes after alcohol use disorder (AUD) treatment among individuals who achieved complete abstinence and those who returned to lower and higher levels of consumption.

Data were collected from individuals with AUD (n = 68) approximately 8 months after the initiation of treatment. Using risk drinking levels defined by the World Health Organization, participants were classified as abstaining (AB) or relapsing with low (RL) or higher (RH) levels. Data were also obtained from 34 age-matched light/non-drinking controls (LN). All participants completed a 1.5 T magnetic resonance imaging session and volumes for 34 bilateral cortical regions of interest were quantitated with FreeSurfer. Generalised linear models were used to examine group differences in cortical volume. All group findings are significant at an FDR-corrected value of 0.018.

Adjusting for age and intracranial volume, significant group differences were found in 13/34 cortical regions. AB showed greater volumes than RL in 2/13 regions and RH in 6/13 regions. RH demonstrated significantly smaller volumes than LN in 12/13 ROIs, whereas RL differed from LN in 9/13 regions. RH and RL differed in only two cortical regions.

Individuals who consumed low-risk levels of alcohol post-treatment exhibited regional cortical volumes more similar to abstainers than individuals who returned to higher-risk levels. This suggests that low-risk levels of alcohol consumption are associated with brain integrity that is comparable to that seen with complete abstinence. Given the previously demonstrated improvement in psychosocial and physical health with reduced levels of alcohol consumption post-treatment, harm reduction may be a beneficial and more attainable goal for some individuals with AUD who are seeking treatment.


ACER article – Non-abstinent recovery in alcohol use disorder is associated with greater regional cortical volumes than heavy drinking (Open access)


Healthline article – Alcohol Use: Cutting Back or Quitting May Reverse Brain Shrinkage, Study Finds (Open access)


See more from MedicalBrief archives:


BMJ editorial – Lifetime perspective on alcohol and brain health


Cutting back on final drink of day ‘could improve brain health’


Chronic alcohol use reshapes brain’s immune landscape, driving anxiety and addiction


Why alcohol-free days are important








MedicalBrief — our free weekly e-newsletter

We'd appreciate as much information as possible, however only an email address is required.