Scientists discover hormone that blocks pot "high"

French researchers have discovered that a naturally occurring hormone acts as a defense in the brain against the psychoactive effects of marijuana consumption.

The hormone, pregnenolone reduces the activity of a brain molecule that acts as a cannabinoid receptor.

Researches think the discovery could help people with addictions to marijuana, as well as allowing people to take medical marijuana without the behavioral effects.

The study was published in the journal Science.

About 147 million people globally – or about 2.5 percent of the population – use cannabis, according to the World Health Organization.