The cannabis industry is growing, which may mean bad news for the beer industry, said Vivien Azer of Cowen, an investment firm.

"We view the interaction with alcohol as being the most obvious to us as we think of these products as substitute social lubricants," Azer, managing director and senior research analyst at Cowen, told CNBC.

"Binge drinking rates, for instance, are significantly lower in states where adults have access to adult-use cannabis," Azer, who specializes in the beverage, tobacco and cannabis sectors, told "Fast Money." Friday is "4/20," or the unofficial holiday celebrating marijuana use.

But it's not just on April 20 when people are consuming cannabis. Pot stocks have soared in the last year. Shares of Aurora Cannabis, a Canadian producer of medical cannabis, are up nearly 240 percent in the last 12 months. Cronos Group is also up nearly 240 percent in the same period. And the stock of medical marijuana company Canopy Growth has gained more 200 percent in the last year.

The total U.S. cannabis industry is worth about $50 billion right now and will reach $75 billion by 2030, Azer said.

"It's just that a lot of it is going through the black market right now," she said.

The good news, she said, is that, "the industry is gaining a lot of traction in terms of gaining consumer support."

According to an October 2017 Gallup poll, 64 percent of U.S. adults are in favor of legalizing adult use cannabis — the highest level of support in five decades.

Azer said her firm remains bullish on cannabis and cautious on beer stocks, as she suspects the trend will continue.

"About 80 percent of consumers do report some kind of reduction in alcohol consumption when they're also engaging in cannabis consumption," Azer said.

The top cannabis stocks she expects to outperform are Canopy Growth, the pharmaceutical company MedReleaf and Kush Bottles, a medical wholesaler.



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