Change in salivary cortisol levels in children (aged 9–12 years) with obesity and respiratory diseases during a 28-day spa treatment: a pilot prospective study

• This pilot study provides the first pediatric data on morning salivary cortisol measured before and after a structured 28-day spa treatment program. • These findings offer initial effect-size estimates and suggest that morning salivary cortisol may be feasible to incorporate as a non-invasive marker in future controlled pediatric studies assessing physiological adaptation during spa treatment.