This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This cross-sectional pilot study is designed to examine the early phases of how excess adiposity affects kidney function in young adults. The study will attempt to enroll ten total participants over a one-year period. This is a pilot study designed to generate preliminary data that will be used for sample size calculations for subsequent studies. Young adults, ages 18 to 21 years, who are receiving care at Children's National Medical Center (CNMC) Adolescent Medicine outpatient facilities, will be eligible for study inclusion. Approximately 900 to 1,000 adolescents, ages 12 to 21 years, are seen at the CNMC Adolescent Center every month for routine care. Thirty eight percent of this population is obese.