Study Examines Cannabis Use Patterns and Cognitive Performance in Aging Adults

How do cannabis use patterns affect cognitive performance in older adults without dementia? A recently published study found that cannabis use was not generally harmful, and was even associated with improved cognition, though with some mixed additional results (1). To assess the effect of cannabis on cognition, the study examined data from the United Kingdom Biobank (UKBB), which contains data on over 500,000 individuals over age 40 across Great Britain from 2006-2010. The study noted the rise of cannabis use in older adults and the need for more investigation into its effects on age-related cognitive performance, as research on cognitive function in individuals past middle age is inconsistent and limited. The study, “History of cannabis use and cognitive function in older adults: findings from the UK biobank,” was published in Age and Ageing in November 2025.

Study Design: Cannabis Use and Cognition

The study consisted of a cross-sectional and longitudinal analysis. Researchers examined data from the UKBB on participants aged 60 years old and older. The cross-sectional analysis included 67,713 participants and the longitudinal analysis included 52,002 participants. The average was 67 years old.

Cognitive data was collected from the years 2014–2019, while data on cannabis use was collected from self-reported questionnaires from the years 2016–2017 and 2022–2023. Cognitive tests included attention and executive function, processing speed, visual memory, and working memory.

The researchers examined past and current cannabis use as well as patterns of use, which included age of initial cannabis use, frequency, and duration (short term or long term). Participants were classified as either lifetime users or no lifetime users. Lifetime users were also categorized as current (use within the past year) or former (last use over a year prior) consumers. Regular cannabis use was coded as more than once per month.

Results: A Complex Relationship

Overall, cannabis use was not found to be universally harmful to cognition in the participants, and past cannabis use was even associated with better cognitive performance, though some inconsistencies were also found. Highlighted results include:

• Out of the total number of participants, 17% reported cannabis use at least once in their lives, and among those participants, 4% had used cannabis in the past year
• From the cross-sectional analysis, lifetime users were found to perform better across all cognitive domains compared to those without a history of cannabis use
• Current use of cannabis was associated with better working memory

Some mixed results were also seen. For example, early onset of cannabis use, duration, and frequency of use demonstrated an association with improved attention and visual memory, while past use was linked with a slower decline in executive function, yet former users who started cannabis before age 17 demonstrated poorer working memory compared with those who started cannabis at a later age.

“Past use was linked to better performance and slower decline in some cognitive domains,” the researchers explained. “However, specific usage patterns, such as longer duration, were associated with poorer outcomes in other domains. These findings highlight the need for further research to clarify underlying mechanisms and guide evidence-based recommendations regarding cannabis use in aging populations.”

Limitations to the Study

The researchers did note the potential for recall bias as a potential limitation. Additionally, the data did not distinguish between medical and recreational cannabis use. The dose, cannabinoids, and method of administration were also not included.

Research on Cannabis and Dementia

One recently published randomized, double-blind, placebo-controlled, clinical trial examined the effect of an extract containing THC and CBD in individuals with dementia (2). Results indicated that the low-dose extract over six months demonstrated alleviated cognition loss. The study, “A randomized clinical trial of low-dose cannabis extract in Alzheimer's disease,” was published in the Journal of Alzheimer’s Disease in October 2025.

Additionally, the November installment of the monthly Healer webinar included a discussion on this study and others on the effects of cannabinoids for symptoms of Alzheimer’s disease, highlighting the potential to improve cognition and manage behavioral symptoms (3).

References

1. Sznitman, SR.; Vered, S.; Weinstein, G. History of cannabis use and cognitive function in older adults: findings from the UK biobank. Age and Ageing. 2025, 54(11). DOI: 10.1093/ageing/afaf319
2. Colli, M. Cognitive Improvements Witnessed with THC-CBD Cannabis Extracts and Dementia Patients. November 10, 2025. https://www.cannabissciencetech.com/view/cognitive-improvements-witnessed-with-thc-cbd-cannabis-extracts-and-dementia-patients (accessed 2025-12-03).
3. McEvoy, E. Updates on Cannabis Research for Alzheimer’s Disease Symptoms. November 20, 2025. https://www.cannabissciencetech.com/view/updates-on-cannabis-research-for-alzheimer-s-disease-symptoms (accessed 2025-12-03).