Researchers have found that a daily dose of cannabis extract could reverse the cognitive decline that happens in the brain as we age.
The University of Bonn study showed regular low doses of tetrahydrocannabinol (THC), the active ingredient in cannabis, dramatically improved memory and learning in older mice with the benefits lasting for weeks after the trial.
The scientists gave a month-long course of the drug to mice aged two months, one year and 18 months and then tested how well they did on cognitive tasks, such as solving a maze and recognising mice they had met before.
In the control group without the drug, the young mice clearly outperformed the middle-aged and elderly mice. But given the THC, the younger mice struggled while the older mice improved so much their scores matched those of drug-free young mice.
Slowing the ageing process
The researchers say this could be because the drug replicates the effect of the naturally occurring cannabinoids produced in our bodies – which reduce as we get older and contribute to the ageing of our brains.
Further study showed that the drug boosted the number of connections between brain cells in the hippocampus, which controls memory.
The scientists now plan to conduct human trials later this year to see if it has the same effect on us.
So if they prove a success, will doctors start prescribing joints to us ‘oldies’?
It’s unlikely, according to team leader Dr Andreas Zimmer. “The dosing is important. Smoking marijuana is very different.”