Can You Use CBD for Alzheimer's Disease? What the Science Says
The scientific evidence supporting CBD’s utility against Alzheimer’s disease has become quite compelling over the last few years. What began as a fringe assessment of a little-known compound has evolved into a multinational effort to establish CBD as a viable adjunctive treatment in the fight against Alzheimer’s and related conditions.
What evidence is there that CBD might be useful for Alzheimer’s disease, and what does it mean about the future of both this non-intoxicating cannabinoid and emerging cognitive care? In this guide, we’ll discuss some of the most pertinent scientific research regarding CBD and Alzheimer’s disease that has been published in the last few years.
CBD for Alzheimer's Disease: Overview
1. As a non-intoxicating and abundant cannabinoid with a minimal side effect profile, CBD is an ideal compound to investigate as an Alzheimer’s treatment2. Laboratory research into the bioactivity of CBD reveals that it interacts with systems involved in the pathogenesis of Alzheimer’s disease
3. Clinical studies are also beginning to shed light on the usefulness of CBD for Alzheimer’s
4. More research is needed, but using CBD for Alzheimer’s disease appears to be supported by the most recent scientific evidence
Most Recent Research on CBD and Alzheimer's Disease
2023: Regulatory role of the endocannabinoid system on glial cells toward cognitive function in Alzheimer’s disease
Alzheimer’s disease is primarily caused by the activation of glial cells, which then cause damaging inflammation in the brain. This research review was based on 26 separate studies and found that “[t]rends were observed toward neuroprotection, as represented by decreased levels of glial cell markers[.]” In the end, the researchers were led to conclude that “endocannabinoid stimulation promotes cognitive function via modulation of glial cells by decreasing pro-inflammatory markers.” In essence, it’s possible that CBD’s purported anti-inflammatory properties may even extend to the neurological inflammation that leads to Alzheimer’s disease.
2022: Cannabidiol (CBD) treatment improves spatial memory in 14-month-old female TAU58/2 transgenic mice
This study involving genetically altered mice found that CBD prevents the spatial memory impairment typical of Alzheimer’s disease. The mice had been altered to develop Alzheimer’s disease early in life, and mice that received CBD experienced a reversal of “spatial reference memory.” This evidence indicates that CBD may go beyond simply preventing the symptoms of Alzheimer’s and could even reverse its damage. More research on this subject is sorely needed.
2022: Cannabidiol protects against Alzheimer's disease in C. elegans via ROS scavenging activity of its phenolic hydroxyl groups
Despite being a very simple organism, the roundworm (C. elegans) is often used in medical studies due to its key biophysical similarities to humans. In this study, “CBD was found to alleviate the progression of… AD.” However, CBD did not appear to be helpful for Parkinson’s disease, another focus of this piece of research.
2022: Effect of Cannabidiol on the Neural Glyoxalase Pathway Function and Longevity of Several C. elegans Strains Including a C. elegans Alzheimer's Disease Model
Another 2022 study involving C. elegans came to similar conclusions. Starting by admitting that CBD “functions in a neuroprotective manner,” the researchers went on to describe the results of their research into how CBD’s supposed antioxidant properties might affect the “glyoxalase pathway[,]” a key neurochemical component in the pathogenesis of Alzheimer’s disease. In the end, the researchers “determined that a limited amount of Cannabidiol can prevent… cellular damage… and extend the lifespan and survival of C. elegans.”
2022: Medium-Dose Chronic Cannabidiol Treatment Reverses Object Recognition Memory Deficits of APP Swe /PS1ΔE9 Transgenic Female Mice
Beginning by pointing out that “evidence suggests that CBD possesses therapeutic-like properties for the treatment of AD,” this laboratory study involving mice found that “object recognition deficits and delayed spatial learning… were reversed by CBD treatment.” In the end, the researchers concluded that “medium-dose CBD appears to have therapeutic value for the treatment of particular behavioral impairments present in AD patients.”
CBD for Alzheimer's Disease Human Trials
2023: Oral THC: CBD cannabis extract in main symptoms of Alzheimer disease: agitation and weight loss
Despite receiving quite a bit of attention in the form of laboratory research, the only piece of clinical data on the subject of CBD and Alzheimer’s is quite limited. In 2021, a clinical study consisting of 30 patients was published in Clinical Therapeutics that involved Bedrocan, a cannabis-based pharmaceutical drug containing small amounts of CBD. The study mainly assessed the usefulness of THC for Alzheimer’s, but it did find improvements in 45% of patients.
Additional CBD for Alzheimer's Disease Studies
2021: Understanding the Modulatory Effects of Cannabidiol on Alzheimer’s Disease
Coming from a perspective that already accepts the “neuroprotective effects” of CBD, this review of the available evidence found that recent studies show CBD might “reverse cognitive deficits… and neuronal death” commonly associated with Alzheimer’s disease. Also, it appears CBD prevents the deposit of two key biochemical markers in the progression of Alzheimer’s disease, “suggesting the possibility of delaying AD progression.” The authors further note that CBD appears to exert these benefits primarily by interacting with a receptor called PPAR.
Discussion: Should CBD Be Used for Alzheimer's Disease?
The available evidence indicates that CBD should be considered seriously as a potential treatment for Alzheimer’s disease and related conditions. Potential neurochemical pathways by which CBD may provide these benefits have already been identified, and a plethora of recent studies support the idea that clinical trials of CBD for Alzheimer’s disease are clearly warranted.
In this brief review, we barely scratch the surface of the laboratory studies that have been conducted to determine the usefulness of CBD for Alzheimer’s disease. We lament, on the other hand, the lack of human clinical trials that have been conducted on the subject and call upon the medical science community to further our understanding of the potential relationship between Alzheimer’s disease and CBD.
Regardless of what the science eventually tells us about the usefulness of CBD for Alzheimer’s, there does not appear to be any reason to avoid trying CBD for this condition. The cannabinoid is fully non-intoxicating, and it very rarely causes side effects, which are nearly always mild in nature if they do occur.
Sources
1. Kamaruzzaman, M. A., Romli, M. H., Abas, R., Vidyadaran, S., Baharuldin, M. T. H., Nasaruddin, M. L., Thirupathirao, V., Sura, S., Warsito, K., Nor, N. H. M., Azwaruddin, M. A., Alshawsh, M. A., & Moklas, M. a. M. (2023). Regulatory role of the endocannabinoid system on glial cells toward cognitive function in Alzheimer’s disease: A systematic review and meta-analysis of animal studies. Frontiers in Pharmacology, 14. https://doi.org/10.3389/fphar.2023.1053680
2. Kreilaus, F., Przybyla, M., Ittner, L. M., & Karl, T. (2022). Cannabidiol (CBD) treatment improves spatial memory in 14-month-old female TAU58/2 transgenic mice. Behavioural Brain Research, 425, 113812. https://doi.org/10.1016/j.bbr.2022.113812
3. Zhang, Y., Li, H., Jiang, S., Lu, Y., Peng, Y., Zhao, L., & Wang, X. (2022). Cannabidiol protects against Alzheimer’s disease in C. elegans via ROS scavenging activity of its phenolic hydroxyl groups. European Journal of Pharmacology, 919, 174829. https://doi.org/10.1016/j.ejphar.2022.174829
4. Frandsen, J., & Narayanasamy, P. (2022). Effect of Cannabidiol on the Neural Glyoxalase Pathway Function and Longevity of Several C. elegans Strains Including a C. elegans Alzheimer’s Disease Model. ACS Chemical Neuroscience, 13(8), 1165–1177. https://doi.org/10.1021/acschemneuro.1c00667
5. Coles, M., Watt, G., Kreilaus, F., & Karl, T. (2020). Medium-Dose chronic cannabidiol treatment reverses object recognition memory deficits of APPSWE/PS1ΔE9 transgenic female mice. Frontiers in Pharmacology, 11. https://doi.org/10.3389/fphar.2020.587604
6. Palmieri, B., & MsC, M. V. (2022). Oral THC: CBD cannabis extract in main symptoms of Alzheimer disease: agitation and weight loss. Research Square (Research Square). https://doi.org/10.21203/rs.3.rs-1672277/v1
7. Xiong, Y., & Lim, C. (2021). Understanding the modulatory effects of cannabidiol on Alzheimer’s disease. Brain Sciences, 11(9), 1211. https://doi.org/10.3390/brainsci11091211
