I decided to proceed with the dinner anyway—which quickly turned out to be a huge mistake. The tossed salad conjured dead leaves, reminding me that everything is picked, pruned, and fallen. The meat reminded me that we are all for slaughter. Then the dessert came out. The waiter placed it on the table, flashed us an impish grin, and lit it on fire. That’s when I started weeping.

My boyfriend paid and hustled me out. We returned to our room, where I lay motionless on the bed and clung to its edges so I didn’t fall up. I had, it turned out, gotten too high. Ever since, despite my live-and-let-live attitude toward most things, I’ve considered edible pot to be slightly suspect, a wolf in sheep’s clothing.

This seems to be a common dichotomy when it comes to eating, rather than smoking, cannabis. People who can smoke a bowl and go about their day will find that when they eat a weed candy (or two—is it even working?), they feel like their hands are about to detach from their body. Though cannabis is safer than many other drugs, edibles feel scary to some people because of the heightened delusional symptoms they seem to induce. Famously, the writer Maureen Dowd took a nibble of a pot chocolate and “became convinced that I had died and no one was telling me.” Indeed, in Colorado, edibles are responsible for a disproportionate share of emergency-room visits, relative to their sales.

The refrain you’ll hear from a more seasoned stoner is that people like Maureen and me simply ate too much. We should have had just a little, then waited, then only had more once the initial high wore off. That may be true. But some marijuana researchers (few though they might be, given restrictions on the drug) told me that something else might be happening, too. Edibles and smoked weed are processed into different substances in the body, and they say this allows the two to affect the mind in totally different ways.

According to Nick Jikomes, the principal research scientist at the cannabis website Leafly, the discrepancy comes down to the type of THC, the primary psychoactive compound in marijuana. When you smoke a joint, what goes into your bloodstream is called delta-9 THC. When you eat cannabis, meanwhile, the drug gets processed by your liver into a different compound, 11-hydroxy THC. The two forms are very similar to each other, but the small differences between them can mean they affect the brain in dramatically disparate ways. The 11-hydroxy THC affects you more intensely once it crosses the blood-brain barrier, Jikomes says.

Mike Tagen, a scientific consultant for cannabis companies who has a pharmacology background, agrees that 11-hydroxy THC is far more potent. The molecule, he says, can activate certain receptors in the brain more fully than delta-9 can. It’s “more like the synthetic cannabinoids, like Spice or K2,” Tagen told me. “Those are associated with bad reactions, things like anxiety attacks, paranoia. That might be why you see the strong reaction with edibles.”