You're buying things a second time because you lost the first ones you purchased. You can't fit your car in the garage because it's jam-packed with junk that you just can't bear to throw away. If this sounds like you, you probably aren't a hoarder—particularly if all you need is a long weekend and a little help to clear up your clutter.

Hoarding is a serious mental illness that affects 2 to 5 percent of the population, according to the American Psychiatric Association. Not all people go to the extremes featured in hoarding reality shows, but if clutter is affecting your social life, job, family relationships, or personal safety, you could have a problem. Here's what you need to know.

Hoarding starts with normal clutter
It's one thing to always have a pile of mail on your kitchen counter or a messy bedroom closet (they're never big enough). It's another thing to store boxes in your oven.

"When you cross that line and go from using places that are supposed to be for storage, such as closets, to filling your bathtub and dining room table with boxes, you're on your way to hoarding," said Matt Paxton, extreme cleaning specialist and TV personality on Hoarders: Family Secrets.

Hoarders have good intentions
Hoarders have the best of intensions and the worst follow through, said Patrick McGrath, PhD, Chicago psychotherapist and former host of The Learning Channel's Hoarding: Buried Alive. "They see a lawn mower on the side of the road and think, ‘Oh, I can fix that,' forgetting they have 17 in their yard already. They're always getting ready to do something but never get to it."

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Hoarding is often triggered by a major loss
The death of a loved one, divorce, or other traumatic event—even a date gone horribly wrong—can trigger hoarding.

"The hoarded stuff doesn't die, and it will never leave you," McGrath said. "So hoarders are connected to their stuff by memories. It's an emotional connection. Everything has meaning, so by tossing it out you're disrespecting it and the person connected to it."
This connection often makes it extremely upsetting for the hoarder to throw things out and let them go.

Hoarders suffer serious consequences
Filling a house with stuff makes for many health hazards.

"Fires and mold are problems, and injuries can occur when people trip and fall while making their way through little paths in their home they create," McGrath said. "In some cases a service person can't access a furnace when it dies because the hoarding takes up so much room."

Hoarding also creates strained family ties when, for example, grandkids aren't allowed to visit their hoarding grandparents.

"People don't understand the appeal of the hoarded items as the hoarder does," McGrath said.

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Hoarding starts in adolescence
Although hoarding usually doesn't manifest fully until adulthood, the seeds of hoarding are typically planted in adolescence, said Gail Gross, PhD, a nationally recognized family and child development expert, author, and educator. The average age when symptoms first appear is 13, according to the APA.

"There may be a genetic link to hoarding," Gross said.

In fact, a 2008 study published in the journal Genes, Brain and Behavior suggests that a certain gene may lend itself to a greater susceptibility to hoarding. Hoarding symptoms also tend to run in families, according to a 2015 study published in Depression and Anxiety.

Hoarding differs from collecting
Collectors usually keep their items displayed, organized, and even wrapped and sealed, McGrath said."Hoarding is willy nilly all over the place. It also interferes with your life."

A large collection of horse memorabilia, for example, that is displayed in a clean, organized way is not hoarding. But if the items start to pile up, become moldy and dirty, and end up being stashed in the bathtub, that's hoarding, McGrath said. There's no organization to the clutter, which is often stacked precariously or tossed into piles.

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Hoarding is its own mental illness
Initially thought of as a subset of obsessive-compulsive disorder (OCD), hoarding is now considered a separate affliction on its own, McGrath said. Known as "hoarding disorder," hoarding affects a person's ability to maintain relationships, hold down a job, and function normally in general. Hoarders are often indecisive, prone to procrastination and perfectionism, disorganized, and easily distracted, which can contribute to the overall severity of the hoarding.

Hoarders become socially isolated
If a loved one stops inviting you over to their home, they could be embarrassed by the clutter.

"They may meet you at the end of the driveway but not allow you to come inside," Paxton said. "Sometimes you can look toward the top of the windows and see boxes and other items stacked up."

There may be no place to sit or visit comfortably. In addition, children of hoarders often won't bring home friends because the mess embarrasses them.

Hoarding is not about monetary value
It's never about the monetary worth or value of the item itself, Paxton said. "It doesn't matter what it's worth, it's about control. We've found everything from famous artwork to $18,000 in cash in a rat's nest to piles of used diapers."

On some level, hoarders believe that these items will serve them in the future, Gross said. "They feel less anxious and more comfortable by possessing them. In fact, just the thought of eliminating or clearing the clutter creates anxiety, stress, and dysfunction."

Overcoming hoarding requires therapy
Aside from a temporarily cleaner home, hiring a crew to clear out a hoarder's house will do nothing for the person in the long term. In fact, taking things away will only backfire.

"Many hoarders experience a subset of problems that tend to get worse over the years, such as alcohol and drug abuse or anxiety," Gross said. "Cognitive behavioral therapy is most successful, especially when incorporated with medication if necessary."

This approach enables hoarders to lower their stress and anxiety and eventually learn to let go of unneeded objects and clutter. "Through behavior modification and cognitive behavioral therapy, hoarders can give voice to their depression, stress, or anxiety while helping to find healthy ways to reduce their stress, relax, and self manage the hoarding," Gross said.

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This article originally appeared on Health.com.