Signs & Symptoms of Anorexia in Teens

Teen years are full of changes—physically, emotionally, and socially. Appetite shifts, body awareness, and mood swings can all be part of normal development. However, when concerns around food, weight, and body image become intense or rigid, they may signal something more serious. Anorexia nervosa is a potentially life-threatening eating disorder that often begins during adolescence, and its early signs can be subtle.

Many parents struggle to tell the difference between “normal teen behavior” and a real problem. Teens may hide symptoms, minimize concerns, or insist they’re fine even as their health declines. That’s why understanding the signs and symptoms of anorexia in teens is so important—early intervention can dramatically improve outcomes.

At Hillcrest Adolescent Treatment Center, located in Agoura Hills, California, we work with teens facing eating disorders alongside anxiety, depression, and substance use. Our adolescent-focused approach prioritizes early detection, whole-person care, and family involvement to support long-term healing.

Learn more about our teen treatment programs or verify your insurance today.

What Is Anorexia Nervosa?

Anorexia nervosa is an eating disorder marked by an intense fear of gaining weight and a distorted perception of one’s body. Teens with anorexia often restrict food intake significantly, even when they are underweight or medically compromised. Unlike dieting or picky eating, anorexia is driven by overwhelming anxiety around food, control, and self-worth.

What makes anorexia especially dangerous is that many teens do not believe they are sick. Even as physical symptoms worsen, the disorder convinces them they need to eat less, exercise more, or maintain strict rules around food. This internal conflict can delay help unless adults know what to look for.

Physical Signs of Anorexia in Teens

Physical symptoms of anorexia often develop gradually, which can make them easy to miss at first. Weight loss may be explained away as “eating healthier” or “being more active,” while other warning signs may appear unrelated.

Parents may notice that their teen seems constantly tired, cold, or weak. Dizziness, frequent stomach discomfort, hair thinning, dry skin, and brittle nails can also occur as the body struggles with inadequate nutrition. In adolescent girls, missed or irregular menstrual cycles are a common red flag. Fainting or near-fainting episodes are especially concerning and warrant immediate medical attention.

These physical changes are the body’s response to prolonged restriction and can escalate quickly if untreated.

Behavioral Changes Around Food and Eating

Behavioral shifts are often some of the earliest indicators of anorexia. Teens may begin skipping meals, eating extremely small portions, or finding reasons to avoid family meals altogether. Some become increasingly rigid about food choices, cutting out entire food groups or obsessing over calories and ingredients.

You might also notice secretive behaviors, such as hiding food, insisting they’ve already eaten, or becoming defensive when eating habits are questioned. Excessive exercise—especially exercising despite injury, illness, or exhaustion—is another common sign. These behaviors are not about rebellion or control; they are driven by fear and distorted beliefs about weight and self-worth.

Emotional and Psychological Symptoms

Anorexia is as much a mental health condition as it is a physical one. Emotional changes often appear long before significant weight loss becomes noticeable.

Teens with anorexia may show increased anxiety, irritability, or mood swings. They may withdraw socially, become unusually perfectionistic, or express intense dissatisfaction with their body regardless of reassurance. Many struggle with low self-esteem and tie their sense of worth to appearance, achievement, or control over food.

Depression is also common, and some teens experience difficulty concentrating or staying engaged in school. These emotional symptoms often intensify as nutritional deprivation affects brain function.

Health Risks of Anorexia During Adolescence

Anorexia carries serious medical risks, particularly during adolescence when the body and brain are still developing. Prolonged restriction can affect heart function, bone density, hormones, and the immune system. Growth and puberty may be delayed, and long-term complications can occur if treatment is postponed.

Because some teens continue to perform well academically or socially, the severity of the disorder is sometimes underestimated. However, anorexia has one of the highest mortality rates of any mental health condition, underscoring the importance of early and comprehensive care.

Co-Occurring Mental Health and Substance Use Concerns

Anorexia rarely exists in isolation. Many teens also struggle with anxiety disorders, depression, obsessive-compulsive traits, or trauma. Some turn to substances as a way to cope with emotional distress, control appetite, or manage overwhelming thoughts.

At Hillcrest, we understand that treating eating disorders effectively means addressing these co-occurring challenges together. Integrated care helps reduce relapse risk and supports deeper, more sustainable recovery.

When to Seek Professional Help

If you’re noticing persistent changes in eating habits, weight, mood, or behavior, it’s important to trust your instincts. Waiting for symptoms to become “severe enough” can delay critical care.

Professional support is especially important when food restriction interferes with daily life, physical symptoms are present, emotional distress is escalating, or substance use is involved. An adolescent-focused evaluation can clarify what’s happening and determine the appropriate level of care.

How Hillcrest Adolescent Treatment Center Supports Teens

Hillcrest Adolescent Treatment Center provides compassionate, evidence-based treatment for teens struggling with eating disorders and co-occurring mental health or substance use issues. Our programs are designed specifically for adolescents, recognizing their unique developmental and emotional needs.

Treatment emphasizes safety, emotional regulation, healthy coping skills, and family involvement. By addressing both the symptoms and the underlying drivers of anorexia, we help teens rebuild a healthier relationship with food, their bodies, and themselves.

Contact Us For Support

If you’re searching for “Signs & Symptoms of Anorexia in Teens,” chances are you’re concerned about a teen you love. That concern can be the first step toward healing.

At Hillcrest Adolescent Treatment Center in Agoura Hills, California, we’re here to help families navigate eating disorders with clarity, compassion, and expert care. If you have questions or want to explore treatment options, contact Hillcrest today. You don’t have to face this alone—and support is available.