Researchers from University Hospital Bonn (Germany) and Hebrew University (Israel) published a 2017 study in the journal Nature Medicine that found long-term, low doses of THC (the active compound in cannabis) reversed cognitive decline in aged mice.

Key Findings:

THC reactivated mTOR signaling, restoring synaptic plasticity in the hippocampus (a brain area tied to memory).

Older mice given THC showed marked improvement in learning and memory, performing comparably to younger mice.

The treatment mimicked exercise and caloric restriction effects, which are also linked to healthy aging.

Caveat: These effects were not observed in young mice, who actually experienced impairment with THC—highlighting age-specific impacts.