Healthy weight can mask dangerous eating disorders in children, paediatricians warn

Rapid weight loss, falling growth percentiles and subtle physical changes may signal an eating disorder even when a child remains within the usual weight range.

A child’s weight does not have to fall below the normal range for an eating disorder to be present, paediatricians warned at the American Academy of Pediatrics’ 2026 National Conference in San Diego. Michelle Odette and Marissa Raymond-Flesch, both from the University of California, San Francisco, told colleagues that rapid weight loss, shifts in growth patterns and subtle physical changes can all be early clues, even when a child still appears to be at a healthy weight.

Raymond-Flesch said anorexia nervosa is often associated with clear underweight, but that view can obscure a diagnosis known as atypical anorexia nervosa. In that form of the illness, children and adolescents show the same restrictive eating, fear of weight gain and related behaviours seen in classic anorexia, yet their body mass index remains at or above the low end of the usual range. Health systems such as Johns Hopkins Medicine and the Cleveland Clinic say the condition is frequently missed for exactly that reason, despite the risk of serious medical complications.

That point was illustrated by a 13-year-old girl who lost 30 pounds over nine months but still remained in the 90th percentile for her age. Raymond-Flesch said the girl had been fasting, cutting portion sizes and walking for up to two hours a day in an effort to avoid bullying about her weight. The case underlined an important clinical lesson: what matters is not only the number on the scale, but how that number compares with a child’s own previous growth trajectory. A drop from one stable percentile band to a much lower one may still leave the child within a “normal” range, yet still signal danger.

Odette urged clinicians not to dismiss low heart rate in an athletic child as simple training effect when it appears alongside weight loss. She also pointed to broader, less specific complaints that can be easy to overlook, including tiredness, dizziness and difficulty concentrating in class. Raymond-Flesch added menstrual changes to the list of warning signs. Odette also said doctors should ask about GLP-1 weight-loss medicines if there is rapid weight loss or if such drugs are present in the home, because some young people may use medication from relatives to suppress appetite.

Experts outside the conference said routine weigh-ins can be an opening for conversation rather than a mechanical check. Cynthia M. Bulik, a professor at the University of North Carolina at Chapel Hill’s Gillings School of Global Public Health, said clinicians have “a golden opportunity” to ask how children feel about their weight when they step on the scale. She said a simple question can reveal distress that might otherwise stay hidden. Bulik, Odette and Raymond-Flesch reported no disclosures.