The Nuance

Do Different Strains of Marijuana Cause Different Highs?

Cannabis researchers say popular notions of indica and sativa are “nonsense”

Photo by Get Budding on Unsplash

Every week, the Nuance will go beyond the basics, offering a deep and researched look at the latest science and expert insights on a buzzed-about health topic.

People well acquainted with marijuana will likely know the difference between sativa and indica, which are the two species of the cannabis plant from which most varieties or “strains” are bred. “If you go into any dispensary, you’ll hear sativa described as being activating or uplifting and euphoric, while indica is said to be calming or sedating,” says Sean Myles, a research chair and associate professor of agricultural genetics at Canada’s Dalhousie University.

Depending on the type of experience you’re looking for, you may lean — or be guided by a dispensary employee — toward a sativa- or indica-dominant strain, or even a “pure” strain, which you may be told is 100 percent one species or the other. For example, Purple Kush is usually marketed as 100 percent indica, while White Widow is often described as a 60–40 percent split between the two species.

All of this is fantastic product marketing. It suggests a level of botanical and biochemical precision that is comforting to consumers — whether you’re using cannabis recreationally or to relieve an affliction (or a bit of both). Unfortunately, a lot of it is bunk.

“The evidence we have to date shows that indica and sativa labeling as currently applied to consumer products is not a reliable indicator of genetics or ancestry, or even of the plant contained within the package,” Myles says.

In a 2015 study in PLOS One, Myles and colleagues genotyped more than 80 commercially available varieties of cannabis. They found that the indica/sativa distinctions advertised on a product’s packaging were wildly inaccurate. “Some strains labeled 100 percent indica were more closely related to a strain labeled 100 percent sativa than any other indica strains in the data set,” he says.

Maybe more troubling: There was little genetic consistency among strains being sold under the same name. “So, all these strains —…