High Prevalence of Muscle Loss Observed in Children with IBD: Study

Crohn’s disease emerged as a strong predictor of low lean mass. Children diagnosed with Crohn’s were significantly more likely to present with low AppLSTMI, when compared to those with ulcerative colitis. Ethnicity also played a role, where children of Asian descent had nearly four times higher odds of having low lean mass despite normal BMI, while Black children were less likely to exhibit this condition.

Other risk factors included active disease, elevated platelet levels and glucocorticoid (steroid) use. Girls in the study had notably lower fat mass when compared to boys, but FMI (fat mass index) rarely fell below the clinical threshold for concern.

Also, none of the children showed fat mass index Z-scores below –2, suggesting that fat stores may be relatively preserved even when muscle mass is significantly depleted. This finding further reinforces the inadequacy of BMI as a standalone nutritional marker in pediatric IBD.

This detailed analysis revealed that among the 112 children with normal BMI but low lean mass, the strongest associations were again seen with Crohn’s disease and elevated platelets. Overall, this study found that lean mass deficits in children with IBD are common and often hidden behind a “normal” BMI reading.

Source:

Alexander, E., Stein, R., Rudra, S., Albenberg, L., & Zemel, B. (2025). Clinical risk factors for body composition deficits in children with inflammatory bowel disease. Journal of Pediatric Gastroenterology and Nutrition. https://doi.org/10.1002/jpn3.70075