The term “OCD” has become somewhat synonymous with any type of behavior that could be described as a little, well, fastidious, picky, or particular about doing things a certain way. Understandably, for those who actually have obsessive-compulsive disorder, that can be annoying at best. For some, the widespread casual use of “OCD” trivializes what is a complex, often misunderstood, and frequently debilitating mental illness.

So it’s no surprise that Riverdale actress Lili Reinhart caused a stir following her recent appearance on The Tonight Show Starring Jimmy Fallon, when she said the fake vomit used on set in the movie Hustlers (her character Annabelle throws up whenever she gets nervous) was an OCD trigger for her.

“It was actually animal crackers and Sprite mixed together,” Reinhart told Fallon. “I thought I was going to have a problem here because I have this really like OCD thing with floaters in water and in drinks. Like if my drink has a little floater in it, I’m like [gags], get it out. That’s when I want to throw up! So having a cup of something that basically looked like ‘floaters’ in water was like my worst nightmare.”

This week, Reinhart responded to suggestions that she was being flippant about OCD and set the record straight: she does have OCD. “I just want to put out there re: my Fallon interview––I actually do suffer from OCD, it wasn’t just a little quip I made on a talk show,” she wrote on Twitter. “I’ve had OCD since I was in elementary school. So yes. I do have the right to talk about it. Thanks.”

The line between actual obsessive-compulsive disorder and just being a bit anal about stuff can be tough to identify. That's often because many people engage in some of the rituals associated with OCD—while some people have a subclinical version of the disorder.

“Almost everyone washes their hands sometimes when they don’t need to,” Jonathan Abramowitz, PhD, director of the University of North Carolina Anxiety Disorders Clinic, previously told Health. He added that it would be difficult to find someone who hasn’t had an obsession or compulsive urge at some point.

“For most of us, those things don’t cause lots of distress, interfere with our jobs or relationships, or take an inordinate amount of time––and that’s what differentiates people with clinical OCD from everyone else,” said Abramowitz.

While the Diagnostic and Statistical Manual of Mental Disorders doesn’t classify OCD into subtypes, many psychologists agree that there are two main types. “I think about OCD in terms of types that involve fear versus types that involve nervous system discomfort,” Kristin Bianchi, PhD, a licensed clinical psychologist who specializes in treating obsessive-compulsive spectrum disorders like OCD, previously told Health.

People with fear-driven OCD carry out obsessive or compulsive behaviors (called rituals) that stem from a strong belief that if they don’t, the things they fear will actually happen. For instance, someone who repeatedly checks that their doors are locked may fear that harm will come to their loved ones if they don’t make those checks.

On the other hand, people with OCD driven by nervous system discomfort may feel the need to do some rituals over and over without a particular reason why other than a strong feeling of discomfort if they don’t. “People with this kind of OCD usually don’t know why something bothers them, and they’ll often describe it as just feeling not quite right,” said Bianchi. “It’s not so much that they’re afraid something bad will happen.”

It’s not clear which type of OCD Reinhart has, or what treatment she’s received for it. But she told Glamour UK earlier this month that therapy plays a positive role in her life.

"Seeing the therapist allowed me to be understood,” she said. “The goal for me has been to always leave therapy feeling a couple of inches taller. Feeling like I've alleviated myself of a problem by learning how to solve it. Not everything has a straight answer—it's not just going to take one session—but I start to think, 'I've grown, I've done this, I've figured this out, now can I go off into the world and try to put what I've learned into action.' That's how I look at therapy. I am not crazy, and I am not problematic. I am just a human who's feeling something in a different way than some other people would."

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