Weed’s gotten a bad rap for years. Reefer Madness, fear-mongering PSAs, and countless after-school specials have made pot seem like a drug that causes people to commit heinous acts of murder and, like, dance too much.

Because of this stigmatization, there are quite a few myths and misunderstandings floating around. We're here to set the record straight.

But first, let’s get to know marijuana a bit more. There are over 400 chemical compounds in marijuana, but the two we know the most about are two cannabinoids called tetrahydrocannabinol (THC) and cannabidiol (CBD). They work by stimulating receptors in the brain, triggering chemical reactions that affect the mind and body.

THC is what causes the cerebral high people often associate with marijuana use, but it’s also responsible for some of the negative side effects, such as paranoia and anxiety. CBD is the yin to THC's yang: It has a nonpsychoactive effect that researchers believe helps reduce anxiety, inflammation, and even depression. For a more in-depth explanation of how weed works in your brain, check out our article here.

Now that you understand the difference, let’s jump in.

Myth: The munchies aren’t real.

Fact: Munchies and stoners go together like peanut butter and jelly. But there’s more to this stereotype than you might think.

In a study performed on mice, scientists found marijuana causes hunger by hijacking part of the brain—the hypothalamus (you've probably have heard of this brain mecca before: It’s the section responsible for hunger, libido, sleep, and more). Scientists injected cannabinoids into a specific section of each mouse's hypothalamus and found the neurons that regulate and suppress sexual arousal, alertness, and hunger actually worked harder under the influence of the cannabinoids. The result? Rampant hunger.

“We were surprised to find that the neurons we thought were responsible for shutting down eating were suddenly promoting hunger,” the study's lead author, Tama Horvath, Ph.D., said in a release at the time. “[The cannabis] fools the brain’s central feeding system.”

Myth: Weed now isn’t as strong as it used to be.

Fact: "The quick and dirty summary is that the concentration of THC in cannabis now is way higher than it used to be,” says Ryan Vandrey, Ph.D., an associate professor who studies cannabis and nicotine at Johns Hopkins University. “People who are good at plant biology have gotten into cannabis and selectively bred plants to be higher in THC.”

But that doesn't necessarily mean everyone is getting higher than their parents did in the 60s. "Potency does not equal dose," says Vandrey. "That’s something people often get confused." In other words, pot smokers today might smoke less weed to achieve the same high.

Myth: All weed produces the same kind of high.

Fact: Most people believe there are only two species of marijuana plants: indica and sativa. Scientists can't exactly agree on whether that's true, but for the sake of making things easier, we’ll stick to these two.

Sativa is a tall plant with narrow leaves that is widely believed to produce a cerebral, psychoactive effect, while indica (typically shorter with wider leaves) is known for producing relaxing, sedating feelings for users. Discriminating the effects of Cannabis sativa and Cannabis indica: a web survey of medical cannabis users. Pearce DD, Mitsouras K, Irizarry KJ. Journal of alternative and complementary medicine (New York, N.Y.), 2014, Sep.;20(10):1557-7708. However it's tough to predict the exact reaction a person will have to each plant. Researchers are continuing to explore the differences between them, including the levels of THC and CBD each contain. For more on that, go here.

Myth: Synthetic marijuana is safe.

Fact: Wrong, wrong, wrong, wrong, wrong. Synthetic marijuana—also known as spice, K2, and fake weed—can be up to 100 times stronger than natural marijuana, and you'll be hard-pressed to find a spice that's manufactured safely.

Originally created in a lab as a way to find out how cannabinoids affect the brain, synthetic marijuana has been marketed as a safe, legal version of weed. Once the DEA caught on to its insane side effects—hallucinations, stroke, vomiting, acute psychosis, even death—it banned the substance. Signs and symptoms associated with synthetic cannabinoid toxicity: systematic review. Courts J, Maskill V, Gray A. Australasian psychiatry : bulletin of Royal Australian and New Zealand College of Psychiatrists, 2016, Aug.;():1440-1665. But because manufacturers can quickly create versions that are subtly different on a chemical level and then label them “not for human consumption,” synthetic marijuana can slip through the DEA’s net and still find its way into head shops and bodegas.

“It’s powerful—much more powerful than natural marijuana,” says Yasmin Hurd, Ph.D., a professor of neuroscience, psychiatry, and pharmacology at the Icahn School of Medicine at Mount Sinai. “It can induce psychosis, because a lot of strains don’t contain CBD, which decreases the anxiety from THC."

Myth: D.A.R.E. helps kids stay away from weed.

Fact: You remember D.A.R.E., right? It was the time in school where you and your buds could straight chill with a bunch of off-duty police officers and talk candidly(ish) about drugs. While the program was massively popular in the 80s and 90s, studies show it doesn't do anything to keep kids from trying drugs. In fact, kids are just as likely to use drugs on the program as they are off it.

The issue is its just-say-no approach, which, as Scientific American put it, is “unlikely to produce lasting effects.” That's because students never learn how to actually communicate with their peers and discuss drugs. D.A.R.E. continues to be used in schools across the country today but has added new elements such as role playing and more interactivity.

Myth: You can’t overdose on weed.

Fact: First you need to understand what an overdose is. An overdose simply means you take more than the normal or recommended amount. So is it possible to overdose on weed? Yes. Symptoms of a (nonlethal) weed overdose include anxiety, paranoia, dizziness, and loss of coordination.

In order to die, a person would need to consume approximately 15,000 pounds of marijuana in about 15 minutes.

Now, is it possible to consume a lethal overdose of weed? Nope. In a 1988 petition, a judge wrote that in order to die, a person would need to consume approximately 15,000 pounds of marijuana in about 15 minutes. Put another way: That's a 154-pound person taking in more than 46 pounds of marijuana at once. So try as you might, it's basically impossible to die from weed.

Myth: You can cheat a urine test.

Fact: You can’t—and won’t. It’s just not going to happen. There are tons of products that claim to flush drugs from your system, but the only true way to “cheat” a urine test is to substitute your pee with someone else's. THC can be detected in a urine test for up to around 10 days for casual smokers and 30 days for chronic users.

“All those [detox] teas do is dilute your urine," says Vandrey, "Most facilities now test for dilution and would flag that sample as being invalid."

Myth: Weed will make you into a criminal.

Fact: Despite the stereotype, taking a bong hit won't instantly send you into a life of crime. In fact, there's never been a clear link between weed and violent crimes. A recent study found marijuana "is not predictive of higher crime rates" and might even be related to lower rates of assault and homicide.

“From the standpoint that it’s illegal to possess cannabis in a state that outlaws it, I guess it does make you a criminal," Vandrey says, "Beyond that, there’s no reasonable sense to think any criminal activity would happen because of smoking marijuana.”

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