Addictions are typically comprised of several symptoms, both physical and psychological. When it comes to substance abuse, you know you’re addicted when you become tolerant to the drug and also experience withdrawal if you stop using it. Addiction is also comprised of an inability or difficulty to control your use, cascading negative consequences, and watching yourself pour money, energy, and emotions into the habit. This will lead to you neglecting other aspects of your life, often leaving you feeling guilty about it.

But drugs and alcohol aren’t the only things you can get addicted to. It seems that in the modern age, the extent of potential addictions is only growing. Researchers have begun identifying such a thing known as the Facebook addiction (and yes, recently researchers have come up with six criteria to diagnose you with a Facebook addiction), and there is even a Center for Internet Addiction to help people cope with cyberaffair, porn, and video game addictions — all of which have become serious issues in the wake of the tech age. You might be surprised to find six more strange addictions below that aren’t as well known as the others.

However, keep in mind that the Diagnostic and Statistical Manual of Mental Disorders (DSM) doesn't necessarily consider internet addictions, or plenty of these other ones, actual clinical addictions. It's harder to define the symptoms of these so-called "addictions" than it is to define the characteristics of drug or alchohol dependency.

Tanning

It may come as no surprise that people are addicted to tanning just as they are to plastic surgery or losing weight. In fact, people who are tanning addicts receive a sort of “high” from going under the UV light and keep doing it, even if they begin to experience adverse health effects, such as blistering, sunburns, or a predisposition to developing skin cancer. According to the Skin Cancer Foundation:

Frequent tanners exhibit signs of both physical and psychological dependence. When a substance causes physical dependency, repeated use of that substance causes symptoms of increased tolerance, craving, and withdrawal. UV light has been shown to increase release of opioid- like endorphins, feel-good chemicals that relieve pain and generate feelings of well-being, potentially leading to dependency.

The best way to prevent a tanning addiction is to educate children about the dangers of indoor tanning and over-exposure to UV light, as many tanners start young in order to achieve that orange glow. Tanning too much can greatly increase your risk for skin cancer, so turn instead to self-tanning creams and sprays that can tint the skin without UV exposure. Many tanning addicts are addicted to the endorphin boost they receive from indoor tanning, so exercise could be a healthier substitute for that rush of feel-good chemicals.

Candy Crush

As online games like Candy Crush are becoming increasingly popular, they have begun to cause addictions in people who are too frequently glued to their screen. As all other addictions, online games have the ability to hold quite an influence over a person’s mind and lifestyle.

Candy Crush in particular has been played well over 200 billion times since it launched in 2012, and according to King, the company that created it, one in 23 Facebook users play it. A survey by Ask Your Target Market, meanwhile, found that 32 percent of Candy Crush players neglected certain aspects of their life to play it, including ignoring friends and family. Players were also far more likely to get distracted at work, and get into arguments with significant others over it. Thirty percent of people in the survey said they were addicted.

“Positive rewards are the main reason people become addicted to things,” Kimberly Young, a pioneering expert on Internet and gaming addictions, told TIME. “When you play the game, you feel better about yourself… When you read the research about gaming, you’re often looking at people who are distracting themselves from something in their lives.”

But like many other video games and social media addictions, people who are addicted to Candy Crush fall into the categories of social addicts, who are constantly trying to activate the pleasure response in their brain: seeing a text light up, a little red Facebook notification appear, or watching their friends’ places in Candy Crush can give you that high. “Look, nobody’s coming to me because they have a clinical addiction to Candy Crush,” Young told TIME. “It’s more of a social addiction, if you will.”

Hair Pulling

Known as trichotillomania, and considered more of a psychological disorder than an addiction, compulsively pulling out your hair is something that up to six million Americans struggle with on a daily basis. People with trichotillomania receive pleasure or gratification when pulling out their hair, and in order to be diagnosed, one must experience an overall impairment in social or occupational functioning.

Pica: Eating Cigarette Ashes, Chalk, and Dirt

Though the disorder appears more in children than adults, pica involves a compulsive pattern of eating non-food substances, like dirt, chalk, paper, or cigarette ashes. In fact, about 10 to 32 percent of children aged 1 to 6 years old manifest this behavior; in adults, however, it’s often the consequence of a lack of certain nutrients, like iron deficiency anemia or zinc deficiency.

Pregnant women who are anemic (lacking iron) often have a strong desire to eat strange materials. Some of the items people with pica gravitate toward include animal feces, dirt, clay, hairballs, ice, sand, and even paint. In order to be diagnosed, the behavior must last for at least one month. Treatment of this “addiction” of sorts is of course to pinpoint the underlying problem — whether it’s malnutrition or a deficiency in iron or zinc — and to improve it. Once the deficiency is taken care of, pica will typically subside within months.

Body Modifications

It’s still debatable whether or not it’s really possible to be physically addicted to tattoos and piercings in and of themselves, but some say that the physiological effects of frequent tattooing can indeed lead to an addiction of sorts. After getting a tattoo or piercing, you get a rush of adrenaline; so it might be more accurate to group so-called tattoo and piercing addictions into adrenaline addictions.

Adrenaline triggers a fight-or-flight response, boosts energy, and releases dopamine, which wards off depression and anxiety. When you’re running on adrenaline, you find it easier to think quickly on your feet and accomplish things, all while being in a better mood. In addition, getting tattoos and piercings can trigger the release of endorphins due to the pain of needles, giving you a natural “high.” Because body modifications can trigger adrenaline and endorphins, people might get addicted to that natural high and keep coming back for more. Once again, perhaps the best fix for feel-good chemicals is exercising rather than turning to body modifications to fuel adrenaline rushes.

Selfies

Yes, selfies can be problematic — at least that’s what some psychiatrists have recently been saying. Though virtually everyone has posted, taken, or at least attempted to take a selfie (even the Pope has taken a selfie) — for some extremists, taking selfies can really overtake their daily functioning. Certain psychiatrists believe that a grating need to constantly take and post pictures of oneself can be a sign of insecurity and need for social validation (Positive feedback, or “likes,” on your Facebook, Instagram, or Twitter can trigger the pleasure response part of your brain). “[T]his is a serious problem,” psychiatrist Dr. David Veale told Mirror News, according to The Huffington Post. “It’s not a vanity issue. It’s a mental health one which has an extremely high suicide rate.”