RT Journal A1 Hernandez DC, Francis LA, Doyle EA T1 NAtional school lunch program participation and sex differences in body mass index trajectories of children from low-income families JF Archives of Pediatrics & Adolescent Medicine JO Archives of Pediatrics & Adolescent Medicine YR 2011 FD April 1 VO 165 IS 4 SP 346 OP 353 DO 10.1001/archpediatrics.2010.253 UL http://dx.doi.org/10.1001/archpediatrics.2010.253 AB In 2007-2008, approximately 36% of US children aged 6 to 11 years were classified as overweight and approximately 20% were considered obese.1 The prevalence of obesity among US children and adolescents aged 10 to 17 years increased by 10% between 2003 and 2007. During the same time period, the prevalence of obesity among girls increased approximately 18%.2 Pediatric obesity has been associated with type 2 diabetes, cardiovascular disease, several types of cancer, and hypertension, especially when tracked into adulthood.3 Obesity among young girls has been associated with early puberty,4- 6 and early puberty among young girls has been linked to unfavorable body image,7- 8 eating problems,9 depression,10 earlier onset of sexual intercourse,11 and breast cancer in womanhood.12- 15