Researchers at the Scripps Research Institute in California found that the active ingredient in marijuana, delta-9-tetrahydrocannabinol (THC), may prevent the progression of Alzheimer’s disease by preventing the neurotransmitter acetylcholine from breaking down and blocking clumps of protein that can inhibit memory and cognition in Alzheimer’s patients.

The researchers said their discovery could lead to more effective drug treatment for Alzheimer’s, the leading cause of dementia among the elderly.

People with Alzheimer’s suffer memory loss, impaired decision-making, and diminished language and movement. Although it is believed to be hereditary, the cause is unknown.

Further reading:

Marijuana may stave off Alzheimer’s - U.S. study, Andy Sullivan October 5, 2006, Reuters.

Potheads send Alzheimer’s up in smoke, Leigh Dayton, Science writer, October 6, 2006, The Australian.