Early use of marijuana might forestall the onset of Alzheimer’s and improve memory in old people, says Gary Wenk, a long-time researcher whose work with marijuana and this disease has come to halt.

“We found out that people who smoked dope in the 1960s were not getting Alzheimer’s,” Wenk said. “These 90-year-olds without dementia were telling us things like, ‘Well, I drank whiskey and smoked dope,’ and these are the things they remember. They don’t remember habits like how often they ate broccoli.”

But lately, due to political, legal and financial reasons, his research progress have come to a halt.

“The evidence in animals is clear but making the leap to humans mean that you have to find a drug company willing to handle the lawsuits and the money,” Wenk said.

Very old rats

Wenk faced other obstacles as well, such as having to compete for approval and grants from the National Institute on Drug Abuse (NIDA), for which so far the University of Mississippi is the only research facility in the nation with a legal, grant-funded marijuana farm.

“I am not funded to do marijuana research,” Wenk said. “It costed me about $100,000 to do a whole experiment, $10,000 just to buy the molecule and every old rat is $150. You can see how things add up and individuals can’t afford these things.”

Before his progress froze, Wenk’s research showed promise to middle-aged Americans. Cannabiniods, chemical compounds in marijuana, may delay the onset of Alzheimer’s to a point where a person is more likely to die of old age before getting the disease.

In his study, Wenk gave rats in his lab at Ohio State University a dosage equivalent to one puff of marijuana every day. In an old rat that was memory impaired due to brain inflammation, the single puff a day was making them smarter. Not only were they smarter, but some of the pathological changes in the rats’ brains were actually being reversed.

“Essentially, what we found was that we know that as people get older, their neurogenesis drops to zero,” Wenk said. “And that’s part of the reason old people have a problem with their memory and depression. What we found was that not only did the single puff a day reverse the memory impairment but also restarted neurogenesis.”

Wenk added that delaying the failure of neurogenesis or the regeneration of neurons helps middle-aged Americans and their families financially.

“If we can keep a person out of a nursing home for five years,” Wenk said. “We’ve saved that family and their insurance companies an awful lot of money… No matter how we spin this, old people are going to win.”

Although the illegality of marijuana has stymied his research, Wenk has also noticed a major shift in cultural tolerance of marijuana, particularly from his students.

“I have really seen a shift in 10 years of increased marijuana tolerance,” Wenk said. “In my class, people are more than willing to discuss their marijuana use. But they would be embarrassed to mention that they smoke cigarettes.”

What about a cure?

Alzheimer’s disease is the sixth leading cause of death in the United States, as more than five million Americans are currently living with the disease that has no cure.

“The problem is that every [medication] seems to work in a young animal because they seem to have young healthy brains,” Wenk said. “But nothing when we take it to the clinics ever seems to help an animal or an old human… Subsequently today, we have virtually nothing useful for Alzheimer’s patients.”

Wenk has researched the effect of Alzheimer’s on animals for about 40 years and shared the findings for studies like these in his book Your Brain on Food.

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