Eating disorders often hide in plain sight. The signs can be subtle, and many people with disordered eating go to great lengths to conceal their behaviors. Roughly 5% of the population meets the criteria for an eating disorder at any given time, and the condition affects people of every age, gender, and body size. Knowing what to look for can help you recognize when someone you care about may be struggling.
Behavioral Changes Around Food
The most telling signs are usually behavioral, not physical. Pay attention to shifts in how someone relates to food and mealtimes. The Mayo Clinic identifies several red flags worth watching for:
- Skipping meals regularly or making excuses for not eating
- An intense focus on “healthy” or “clean” eating that leads them to skip social events like dinners out, birthday parties, or holiday meals
- Insisting on preparing their own food separately from what everyone else is eating
- Eating in secret or hoarding food
- Leaving the table during meals or heading to the bathroom immediately afterward
- Frequent comments about feeling fat, needing to lose weight, or being unhappy with their body
- Withdrawing from friends and social activities they used to enjoy
No single behavior on this list proves someone has an eating disorder. What matters is the pattern: when multiple changes cluster together, when they intensify over time, and when food and body concerns start shrinking a person’s world.
Physical Signs You Can See
Some physical changes become visible as an eating disorder progresses, though many people with serious disordered eating look perfectly healthy on the outside. Dramatic or unexplained weight loss is the most obvious sign, but it’s far from the only one.
Someone who restricts food heavily may develop extreme thinness, muscle weakness, low blood pressure, or a noticeably slow pulse. Fine, downy hair (called lanugo) sometimes appears on the face and arms as the body tries to insulate itself against heat loss. Dry skin, brittle nails, thinning hair on the scalp, and feeling cold all the time are also common.
Purging behaviors leave their own set of clues. Repeated vomiting erodes tooth enamel and causes increasing dental sensitivity and decay. The salivary glands in the jaw and neck can swell noticeably, giving the face a puffy, rounded appearance sometimes described as “chipmunk cheeks.” Calluses or scars on the knuckles of the hand (from inducing vomiting) are another telltale sign. Chronic sore throat, acid reflux, bloating, and other digestive problems often follow.
Severe dehydration and electrolyte imbalances can develop with any form of purging, including laxative and diuretic misuse. These are medically dangerous and can affect heart rhythm, even when someone appears outwardly fine.
Signs That Look Different in Men
Eating disorders in boys and men are widely underrecognized, partly because the warning signs look different. Male body ideals tend to center on muscularity and leanness rather than thinness, so disordered eating in men often revolves around building muscle instead of losing weight.
Muscle dysmorphia, sometimes called “bigorexia,” involves a persistent belief that one’s body isn’t muscular enough, paired with compulsive weight training and rigid control over protein and macronutrient intake. A person with muscle dysmorphia may refuse to miss a workout under any circumstances, obsessively track every gram of protein, or use supplements, creatine, or anabolic steroids to change their appearance. One study of nearly 4,500 young men found that by ages 16 to 25, a quarter reported worrying about not having enough muscle, and 11% had used muscle-building products including steroids.
The key warning sign is rigidity. When someone’s food rules or exercise routine starts interfering with their social life, schoolwork, or ability to be flexible, that’s a meaningful shift. A dedicated gym habit is one thing. Canceling plans with friends because it conflicts with a workout, or refusing to eat at a restaurant because the macros can’t be tracked, is something else.
Signs in Athletes
Athletes face a particular risk because the line between disciplined training and disordered eating can blur easily. A condition called Relative Energy Deficiency in Sport (RED-S) occurs when an athlete consistently burns more energy than they take in, and it can affect nearly every system in the body.
In female athletes, the clearest early warning sign is a change in menstrual cycles. Periods becoming irregular or stopping altogether signals that the body doesn’t have enough energy to maintain normal hormonal function. Over time, this disrupts bone-building processes and can lead to repeated stress fractures, even in young, otherwise healthy athletes. Fatigue, declining performance, frequent illness, and slow recovery from injuries are also red flags.
Male athletes with RED-S typically don’t have such an obvious early indicator. Signs in men include low energy, decreased sex drive, delayed puberty in younger athletes, poor bone health, and stress fractures that keep recurring. Because these symptoms develop gradually and can be attributed to overtraining, they’re easy to miss.
Eating Disorders Without Body Image Concerns
Not all eating disorders are driven by a desire to lose weight or dissatisfaction with appearance. Avoidant/Restrictive Food Intake Disorder (ARFID) involves severely limited eating that has nothing to do with body image. People with ARFID may lose interest in eating altogether, feel intense anxiety about consequences like choking or vomiting, or find certain food textures, colors, tastes, or smells intolerable.
ARFID often looks like extreme picky eating, but it goes well beyond preference. Someone with ARFID may eat only a handful of “safe” foods, follow rigid rituals around how food is prepared or consumed (like eating items in a specific order), and become visibly distressed when these routines are disrupted. The result can be significant weight loss, nutritional deficiencies, and an inability to participate in normal social eating. This condition is especially common in children and adolescents but occurs in adults too.
A Simple Screening Framework
If you’re unsure whether what you’re seeing adds up to a real concern, a widely used screening tool called the SCOFF questionnaire offers a useful framework. It was designed for clinical settings, but the five questions can help you organize your observations:
- Does the person make themselves vomit because they feel uncomfortably full?
- Do they seem to have lost control over how much they eat?
- Have they lost more than 15 pounds in a three-month period?
- Do they believe they are fat when others say they are too thin?
- Does food seem to dominate their life?
A “yes” to two or more of these questions is considered a strong indicator of anorexia or bulimia. You won’t always know the answers from the outside, but even one or two clear “yeses” suggest the concern is worth taking seriously.
How to Start the Conversation
Recognizing the signs is only half the challenge. Bringing it up with someone is the harder part, and how you do it matters enormously. People with eating disorders often feel shame, denial, or fear of losing control, and a confrontational approach almost always backfires.
Choose a private, comfortable setting where the person feels safe. Use “I” statements to frame your concerns: “I’ve noticed you seem really stressed around mealtimes” or “I’ve been worried about you lately” lands very differently than “You need to eat more” or “You’re making everyone worry.” The goal is to open a door, not to diagnose or prescribe solutions.
Ask how you can support them rather than telling them what to do. And if they deny it or push back, which is common, try not to show frustration. Let them know you’re there whenever they’re ready to talk. Planting the seed that someone has noticed and cares can matter more than getting an immediate admission. Recovery from an eating disorder rarely starts with a single conversation, but that first conversation can be the thing a person remembers when they’re finally ready to ask for help.