Elijah Nouvelage / Reuters

The proliferation of retail boutiques in California did not really bother him, Evan told me, but the billboards did. Advertisements for delivery, advertisements promoting the substance for relaxation, for fun, for health. “Shop. It’s legal.” “Hello marijuana, goodbye hangover.” “It’s not a trigger,” he told me. “But it is in your face.”

When we spoke, he had been sober for a hard-fought seven weeks: seven weeks of sleepless nights, intermittent nausea, irritability, trouble focusing, and psychological turmoil. There were upsides, he said, in terms of reduced mental fog, a fatter wallet, and a growing sense of confidence that he could quit. “I don’t think it’s a ‘can’ as much as a ‘must,’” he said.

Evan, who asked that his full name not be used for fear of professional repercussions, has a self-described cannabis-use disorder. If not necessarily because of legalization, but alongside legalization, such problems are becoming more common: The share of adults with one has doubled since the early aughts, as the share of cannabis users who consume it daily or near-daily has jumped nearly 50 percent—all “in the context of increasingly permissive cannabis legislation, attitudes, and lower risk perception,” as the National Institutes of Health put it.

Public-health experts worry about the increasingly potent options available, and the striking number of constant users. “Cannabis is potentially a real public-health problem,” said Mark A. R. Kleiman, a professor of public policy at New York University. “It wasn’t obvious to me 25 years ago, when 9 percent of self-reported cannabis users over the last month reported daily or near-daily use. I always was prepared to say, ‘No, it’s not a very abusable drug. Nine percent of anybody will do something stupid.’ But that number is now [something like] 40 percent.” They argue that state and local governments are setting up legal regimes without sufficient public-health protection, with some even warning that the country is replacing one form of reefer madness with another, careening from treating cannabis as if it were as dangerous as heroin to treating it as if it were as benign as kombucha.

But cannabis is not benign, even if it is relatively benign, compared with alcohol, opiates, and cigarettes, among other substances. Thousands of Americans are finding their own use problematic in a climate where pot products are getting more potent, more socially acceptable to use, and yet easier to come by, not that it was particularly hard before.

For Keith Humphreys, a professor of psychiatry and behavioral sciences at Stanford University, the most compelling evidence of the deleterious effects comes from users themselves. “In large national surveys, about one in 10 people who smoke it say they have a lot of problems. They say things like, ‘I have trouble quitting. I think a lot about quitting and I can’t do it. I smoked more than I intended to. I neglect responsibilities.’ There are plenty of people who have problems with it, in terms of things like concentration, short-term memory, and motivation,” he said. “People will say, ‘Oh, that’s just you fuddy-duddy doctors.’ Actually, no. It’s millions of people who use the drug who say that it causes problems.”

Users or former users I spoke with described lost jobs, lost marriages, lost houses, lost money, lost time. Foreclosures and divorces. Weight gain and mental-health problems. And one other thing: the problem of convincing other people that what they were experiencing was real. A few mentioned jokes about Doritos, and comments implying that the real issue was that they were lazy stoners. Others mentioned the common belief that you can be “psychologically” addicted to pot, but not “physically” or “really” addicted. The condition remains misunderstood, discounted, and strangely invisible, even as legalization and white-marketization pitches ahead.

The country is in the midst of a volte-face on marijuana. The federal government still classifies cannabis as a Schedule I drug, with no accepted medical use. (Meth and PCP, among other drugs, are Schedule II.) Politicians still argue it is a gateway to the use of things like heroin and cocaine. The country still spends billions of dollars fighting it in a bloody and futile drug war, and still arrests more people for offenses related to cannabis than it does for all violent crimes combined.

Yet dozens of states have pushed ahead with legalization for medical or recreational purposes, given that for decades physicians have argued that marijuana’s health risks have been overstated and its medical uses overlooked; activists have stressed prohibition’s tremendous fiscal cost and far worse human cost; and researchers have convincingly argued that cannabis is far less dangerous than alcohol. A solid majority of Americans support legalization nowadays.

Academics and public-health officials, though, have raised the concern that cannabis’s real risks have been overlooked or underplayed—perhaps as part of a counter-reaction to federal prohibition, and perhaps because millions and millions of cannabis users have no problems controlling their use. “Part of how legalization was sold was with this assumption that there was no harm, in reaction to the message that everyone has smoked marijuana was going to ruin their whole life,” Humphreys told me. It was a point Kleiman agreed with. “I do think that not legalization, but the legalization movement, does have a lot on its conscience now,” he said. “The mantra about how this is a harmless, natural, and non-addictive substance—it’s now known by everybody. And it’s a lie.”

Thousands of businesses, as well as local governments earning tax money off of sales, are now literally invested in that lie. “The liquor companies are salivating,” Matt Karnes of GreenWave Advisors told me. “They can’t wait to come in full force.” He added that Big Pharma was targeting the medical market, with Wall Street, Silicon Valley, food businesses, and tobacco companies aiming at the recreational market.

Sellers are targeting broad swaths of the consumer market—soccer moms, recent retirees, folks looking to replace their nightly glass of chardonnay with a precisely dosed, low-calorie, and hangover-free mint. Many have consciously played up cannabis as a lifestyle product, a gift to give yourself, like a nice crystal or an antioxidant face cream. “This is not about marijuana,” one executive at the California retailer MedMen recently argued. “This is about the people who use cannabis for all the reasons people have used cannabis for hundreds of years. Yes, for recreation, just like alcohol, but also for wellness.”

Evan started off smoking with his friends when they were playing sports or video games, lighting up to chill out after his nine-to-five as a paralegal at a law office. But that soon became couch-lock, and he lost interest in working out, going out, doing anything with his roommates. Then came a lack of motivation and the slow erosion of ambition, and law school moving further out of reach. He started smoking before work and after work. Eventually, he realized it was impossible to get through the day without it. “I was smoking anytime I had to do anything boring, and it took a long time before I realized that I wasn’t doing anything without getting stoned,” he said.

His first attempts to reduce his use went miserably, as the consequences on his health and his life piled up. He gained nearly 40 pounds, he said, when he stopped working out and cooking his own food at home. He recognized that he was just barely getting by at work, and was continually worried about getting fired. Worse, his friends were unsympathetic to the idea that he was struggling and needed help. “[You have to] try to convince someone that something that is hurting you is hurting you,” he said.

Other people who found their use problematic or had managed to quit, none of whom wanted to use their names, described similar struggles and consequences. “I was running two companies at the time, and fitting smoking in between running those companies. Then, we sold those companies and I had a whole lot of time on my hands,” one other former cannabis user told me. “I just started sitting around smoking all the time. And things just came to a halt. I was in terrible shape. I was depressed.”

Lax regulatory standards and aggressive commercialization in some states have compounded some existing public-health risks, raised new ones, and failed to tamp down on others, experts argue. In terms of compounding risks, many cite the availability of hyper-potent marijuana products. “We’re seeing these increases in the strength of cannabis, as we are also seeing an emergence of new types of products,” such as edibles, tinctures, vape pens, sublingual sprays, and concentrates, Ziva Cooper, an associate professor of clinical neurobiology in the Department of Psychiatry at Columbia University Medical Center, told me. “A lot of these concentrates can have up to 90 percent THC,” she said, whereas the kind of flower you could get 30 years ago was far, far weaker. Scientists are not sure how such high-octane products affect people’s bodies, she said, but worry that they might have more potential for raising tolerance, introducing brain damage, and inculcating dependence.

As for new risks: In many stores, budtenders are providing medical advice with no licensing or training whatsoever. “I’m most scared of the advice to smoke marijuana during pregnancy for cramps,” said Humphreys, arguing that sellers were providing recommendations with no scientific backing, good or bad, at all.

In terms of long-standing risks, the lack of federal involvement in legalization has meant that marijuana products are not being safety-tested like pharmaceuticals; measured and dosed like food products; subjected to agricultural-safety and pesticide standards like crops; and held to labeling standards like alcohol. (Different states have different rules and testing regimes, complicating things further.)

Health experts also cited an uncomfortable truth about allowing a vice product to be widely available, loosely regulated, and fully commercialized: Heavy users will make up a huge share of sales, with businesses wanting them to buy more and spend more and use more, despite any health consequences.

“The reckless way that we are legalizing marijuana so far is mind-boggling from a public-health perspective,” Kevin Sabet, an Obama administration official and a founder of the nonprofit Smart Approaches to Marijuana, told me. “The issue now is that we have lobbyists, special interests, and people whose motivation is to make money that are writing all of these laws and taking control of the conversation.”

This is not to say that prohibition is a more attractive policy, or that legalization has proven to be a public-health disaster. “The big-picture view is that the vast majority of people who use cannabis are not going to be problematic users,” said Jolene Forman, an attorney at the Drug Policy Alliance. “They’re not going to have a cannabis-use disorder. They’re going to have a healthy relationship with it. And criminalization actually increases the harms related to cannabis, and so having a strictly regulated market where there can be limits on advertising, where only adults can purchase cannabis, and where you’re going to get a wide variety of products makes sense.”

Still, strictly regulated might mean more strictly regulated than today, at least in some places, drug-policy experts argue. “Here, what we’ve done is we’ve copied the alcohol industry fully formed, and then on steroids with very minimal regulation,” Humphreys said. “The oversight boards of a number of states are the industry themselves. We’ve learned enough about capitalism to know that’s very dangerous.”

A number of policy reforms might tamp down on problem use and protect consumers, without quashing the legal market or pivoting back to prohibition and all its harms. One extreme option would be to require markets to be noncommercial: The District of Columbia, for instance, does not allow recreational sales, but does allow home cultivation and the gifting of marijuana products among adults. “If I got to pick a policy, that would probably be it,” Kleiman told me. “That would be a fine place to be if we were starting from prohibition, but we are starting from patchwork legalization. As the Vermont farmer says, I don’t think you can get there from here. I fear its time has passed. It’s generally true that the drug warriors have never missed an opportunity to miss an opportunity.”

There’s no shortage of other reasonable proposals, many already in place or under consideration in some states. The government could run marijuana stores, as in Canada. States could require budtenders to have some training or to refrain from making medical claims. They could ask users to set a monthly THC purchase cap and remain under it. They could cap the amount of THC in products, and bar producers from making edibles that are attractive to kids, like candies. A ban or limits on marijuana advertising are also options, as is requiring cannabis dispensaries to post public-health information.

Then, there are THC taxes, designed to hit heavy users the hardest. Some drug-policy experts argue that such levies would just push people from marijuana to alcohol, with dangerous health consequences. “It would be like saying, ‘Let’s let the beef and pork industries market and do whatever they wish, but let’s have much tougher restrictions on tofu and seitan,’” said Mason Tvert of the Marijuana Policy Project. “In light of the current system, where alcohol is so prevalent and is a more harmful substance, it is bad policy to steer people toward that.” Yet reducing the commercial appeal of all vice products—cigarettes, alcohol, marijuana—is an option, if not necessarily a popular one.

Perhaps most important might be reintroducing some reasonable skepticism about cannabis, especially until scientists have a better sense of the health effects of high-potency products, used frequently. Until then, listening to and believing the hundreds of thousands of users who argue marijuana is not always benign might be a good start.

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