Leucine Requirements in School-Age Children

Leucine is an essential amino acid, which serves a special purpose of signaling cell growth in muscle in addition to making up protein. Essential amino acids like leucine need to be eaten every day from our foods like meat, dairy, eggs, beans, and nuts, as they cannot be made by our bodies. The current recommendation for leucine in the diet of school-age children are based upon adult needs. This study will measure the leucine requirement in children aged 6-10 years old using an non-invasive technique with special diets, safe stable isotopes, and simple breath collections. Creating guidelines based on measured requirements for leucine in this age group is essential for supporting optimal growth in healthy children.

Inclusion Criteria: * Healthy children * Aged 6 to 10 years at enrollment * Body weight between the 3rd and 85th percentile according to WHO Child Growth Standards * Assent from the child and written informed consent from parent(s) and/or legal guardian(s) Exclusion Criteria: * Diagnosis of any acute or chronic medical condition * Current use of prescription medication that may affect protein or energy metabolism * Recent weight loss * Recent illness (fever, vomiting, severe runny nose within the past 5 days) * Inability to comply with study procedures