Cannabis Reverses Brain Aging in Mice

A new study finds complete reversal of memory loss in older animals.

Posted May 09, 2017

Pixabay; used with permission.
Source: Pixabay; used with permission.

A collaborative study between researchers at University of Bonn, in western Germany and The Hebrew University of Jerusalem in Israel published in the May issue of Nature Medicine found that cognitive deficits—learning and memory losses—in aging mice were completely reversed after just four weeks of receiving a daily low dose of THC, the active ingredient in cannabis products like marijuana and hashish. When the researchers looked at the brain tissue and genetic activity of these mice, they found that the cognitive reversals occurred at a molecular level, which means that physical changes occurred in the brain along with cognitive improvement. The brains of mice who received placebo for those four weeks continued to age normally.

Exciting and hopeful research? Surely. But this is not quite news you can use, at least not yet. The amount of THC given to the study mice was too low to induce a “high,” which suggests that recreational use of cannabis isn’t the answer. (Some existing treatments work that way; for instance, studies of the use of melatonin for sleep issues have found that less is better in many cases.)

Next up are clinical studies to help determine whether or not low-dose THC can do the same for humans and, if so, under what conditions and at what dose. Previous studies have already shown that cannabis reduces inflammation in the brain, improves cognition and helps manage chronic pain. This study suggests we may also be one step closer to understanding and treating dementia.


Bilkei-Gorzo A, Albayram O, Draffehn A, et al. A chronic low dose of THC restores cognitive function in old mice. Nature Medicine. 8 May 2017. doi: 10.1038/nm.4311. [Abstract]

Martin-Moreno AM, Brera B, Spuch C et al. Prolonged oral cannabinoid administration prevents neuroinflammation, lowers B-amyloid levels and improves cognitive performance in APP 2576 mice. Journal of Neuroinflammation. 2012;9(8). doi:10.1186/1742-2094-9-8.

MIT News. Scientists pinpoint dosage of melatonin for insomnia. Oct 17, 2001.  Accessed 9 May 2017.