When I was 13, I was taken out of school for a month to deal with an eating disorder. Yes, I was very thin, but I wasn't concerned with my weight. The issue was that I was terrified of vomiting—a condition called emetophobia—and my restricted eating was a byproduct of that fear. Having nothing in my stomach meant I'd have nothing to throw up. Technically, I had avoidant/restrictive food intake disorder (ARFID), but to the untrained eye—that is, my parents, classmates, and teachers—I had anorexia. 

The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) recognizes three main eating disorders: binge eating disorder, anorexia nervosa, and bulimia nervosa. The rest are classified as an "other specified feeding and eating disorder." That catchall term refers to any type of disordered eating that causes significant distress or impairment, but doesn't meet the specific criteria for the typical eating disorders. And that's leaving a lot of conditions out, which might explain why you're not familiar with the five eating disorders below. (Get control of your eating and change your life in just 3 short weeks with Prevention’s 21-Day Challenge.)

Orthorexia nervosa
We're all interested in healthy eating, but there's a big difference between being mindful of your diet and letting your diet control your mind. While anorexia and bulimia are all about the quantity of food you're eating, orthorexia focuses on the quality of food. A review in the Journal of Human Sport & Exercise defines orthorexics as those who "obsessively avoid foods which may contain artificial colors, flavors, preservative agents, pesticide residues or genetically modified ingredients, unhealthy fats, foods containing too much salt or too much sugar, and other components." Eventually, sufferers start making their own, even more rigid rules and often isolate themselves socially. (Always exhausted? Here are 7 reasons you’re always tired.)

Anorexia athletica
It used to be seen mostly in athletes, but anorexia athletica has become more prevalent thanks to the pervasive "strong is the new skinny" mantra. While anorexics restrict their eating and bulimics purge after meals, AA sufferers compulsively exercise to keep pounds at bay, paying special attention to the number of calories burned. Among all other eating disorders, compulsive exercising has been linked to higher levels of weight and shape concerns fueled by body dissatisfaction, according to research published in the European Eating Disorders Review. Exercise compulsion can also be fueled by the negative symptoms of being unable to exercise. Researchers found that, even after as little as 24 hours with no exercise, AA sufferers experienced guilt, anxiety, depression, and irritability. 

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Diabulimia
According to research in the Journal of Diabetes Science and Technology, women with type 1 diabetes are 2.4 times more likely to develop an eating disorder than those without the condition. But instead of restricted eating or purging, those with this disorder practice insulin restriction: reducing necessary insulin doses or skipping them altogether. By doing this, sugars and calories spill directly into urine and are ultimately flushed out, resulting in rapid weight loss. (Here's what the color of your pee can tell you about your health). But this puts you at a much higher risk of developing infections and diabetic ketoacidosis, which can lead to diabetic coma. The parallels between management of diabetes and disordered eating (like monitoring food portions, blood sugars, weight, and exercise) also make diabulimia difficult to treat. 

Pica
Most people assume it's just a strange tick, but pica—which describes eating nonfood materials like dirt, paint, or paper—is actually a pretty common eating disorder. It's seen mostly in children; between 10 and 32 percent of kids ages 1 to 6 are reported to have had pica. But the condition is also common in pregnant women and those who are iron deficient, because in some cases of the disorder, the cravings stem from nutritional deficiencies (like iron). Aside from the typical malnutrition that plagues many eating disorders, those with pica are also at risk for lead poisoning and intestinal obstructions from consuming indigestible items. (Think you’re too old for an eating disorder? Think again: Here how eating disorders are on the rise among older women.)

Night eating syndrome
This isn't your typical midnight snack. Night eating syndrome (NES) is characterized by excessive nighttime eating, though not necessarily bingeing. According to a study published in the Journal of the American Medical Association, those with NES had only consumed about one-third of their total daily calories by 6 PM, compared to a control group that had eaten almost three-quarters of theirs. The roles reversed between 8 PM and 6 AM, when NES sufferers consumed 56 percent of their calories—the control group only put away 15 percent. Researchers also found that NES was closely related to depression, and because late-night grazing (which is what those suffering from NES do, rather than bingeing) normally involves carb-rich comfort foods, night eating syndrome may be a form of self-medication.

This article originally appeared on Prevention.com.