Last Updated:February 05, 2026, 18:32 IST

The study examined cognitive functions previously linked to cannabis use, including learning, memory, processing speed, attention and executive function.

The research team analyzed data from 26,362 middle-aged and older adults.

A new study from the University of Colorado Anschutz Medical Campus challenges common assumptions about cannabis and the aging brain, finding that older adults who use cannabis showed larger brain volumes and better cognitive function compared to non-users. The research, published in the Journal of Studies on Alcohol and Drugs, examined over 26,000 adults ages 40 to 77 and found generally positive associations between lifetime cannabis use and brain health- a surprising contrast to much of the existing research focused on younger populations.

Lead researcher Anika Guha said, “More older adults are using cannabis. It’s more widely available and is being used for different reasons than in younger folks such as for sleep and chronic pain. Plus, people are living longer. We have to ask, ‘What are the long-term effects of cannabis use as we continue to age?'”

What Study Found?

The research team analyzed data from 26,362 middle-aged and older adults and discovered that greater lifetime cannabis use was generally associated with larger volumes in specific brain regions and better performance on cognitive tests. The researchers focused on brain areas with high concentrations of CB1 cannabinoid receptors- the parts of the brain most likely to be affected by cannabis. They also examined cognitive functions previously linked to cannabis use, including learning, memory, processing speed, attention and executive function.

“One of the things that was really interesting was that although for almost everything we looked at, there was this positive relationship, there was a single brain region where we saw that higher cannabis use was actually associated with lower brain volume,” Anika Guha noted, referring to the posterior cingulate, part of the brain’s limbic system.

Why Does Brain Volume Matter As We Age?

As people grow older, brain volumes typically shrink due to processes like atrophy and neurodegeneration. This decrease often correlates with declining cognitive function and increased dementia risk.

“We also know that as we age, we often see smaller brain volumes due to processes like atrophy and neurodegeneration,” Anika Guha explained, adding, “In this sense, we could think of larger brain volumes in the context of aging as possibly reflecting maintained brain volume and preserved cognitive function.” The hippocampus, a brain region crucial for memory and implicated in dementia, was among the areas showing positive associations with cannabis use.

Were Results Different For Men And Women?

Yes. The research revealed significant differences between sexes, though the pattern wasn’t straightforward. The team examined sex as a key factor for two reasons: men and women use cannabis differently and report different effects, and preclinical research shows the endocannabinoid system- the body’s network of cannabinoid receptors- differs between sexes, including variations in receptor density and complex interactions with hormones.

“While there wasn’t a clear-cut or consistent pattern, like male cannabis users always showing more favorable effects than women, we did see significant interactions across several brain regions and cognitive measures,” Anika Guha said.