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Obesity and Early Puberty. Pauline Williams, MPA, RD, CD. Prevalence Overweight. Tanner Stage Girls. Tanner Stage Boys. Tanner Stage.
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Obesity and Early Puberty Pauline Williams, MPA, RD, CD
Prevalence Overweight DP Williams 2007
Tanner Stage Girls DP Williams 2007
Tanner Stage Boys DP Williams 2007
Tanner Stage • Middle Adolescence (Stages 3 and 4): acceleration of weight and growth as well as secondary sex characteristics. Pubic hair first, then axillary, then facial hair. • Female: menarche (average age 12 years) - can occur in Stages 1 and 2; usually 3 and 4 factors affecting: nutrition, genetic - age of mother’s menarche. • Male: gynecomastia also appears during middle adolescence: up to 70% of normal males DP Williams 2007
Reported Maturation • 1974 Frisch hypothesized “critical body weight” necessary for onset of puberty DP Williams 2007
Chicken or Eggwhich came first • Increased obesity is leading to early puberty • Early puberty is leading to increased obesity • Fact: Obesity and early puberty are related DP Williams 2007
Early puberty associations • BMI at 36 months • Rate of change of BMI between 36 months and age 6 • Early age of maternal menarche • Nonwhite race DP Williams 2007
Evidence • Lee, JM, et al. Weight Status in Young Girls and Onset Puberty (2007) • 354 girls • Longitudinal • Ht, wt, assessment of pubertal stage • Measured at • 36 months, 54 months • Grades 1,4,5, and 6 DP Williams 2007
Results • Lee et al (2007) • Higher BMI at 36 months • Higher rate of change of BMI • By grade 4; 30% were at risk or overweight • Both associated with early puberty • Increased body fatness precedes onset of puberty DP Williams 2007
Evidence • Ribeiro, P, et al Association between overweight and early sexual maturation in Portuguese boys and girs (2005) • 382 boys, 437 girls • Cross-sectional • BMI, skinfolds, Tanner stage • Ages 10-15 DP Williams 2007
Results • Ribeiro et al (2005) • Overweight higher in early maturing boys and girls (30.5%, 32.7%) • Lower prevalence overweight in late maturing boys and girls (20.3%, 18.3%) • Association between early sexual maturity and prevalence of overweight in both genders DP Williams 2007
Evidence • McCartney, R, et al Obesity and Sex Steroid Changes across Puberty (2006) • 30 normal weight 74 obese peripubertal girls • Cross-sectional • BMI, Tanner stage, blood tests (testosterone, fasting insulin, progesterone, LH) DP Williams 2007
Results • McCartney et al (2006) • Peripubertal obesity associated with high hormone levels and high insulin levels • Known association between childhood obesity and insulin resistance and hyperinsulinemia • High insulin may lead to adult polycystic ovary syndrome (PCOS) DP Williams 2007
Pubertal Timing Controversy? • Syper Review (2006) • Tanner stage may be overestimated • Adipose tissue can resemble true breast tissue • Evidence not conclusive that early puberty is due to obesity; ? Early puberty leads to obesity? • More longitudinal studies DP Williams 2007
Consequences of Early Puberty • Psychiatric disorders • Deficit in psychosocial functioning • Early initiation of alcohol, sexual intercourse, and teenage pregnancy • Increased rates of adult obesity • Increased rates of reproductive cancers DP Williams 2007
Review • Puberty beginning 6 months to 2 years earlier • Obesity and early puberty are associated • High BMI at 36 months • Rate of change of BMI by first grade • Cause and effect? • Other associations • Early age maternal menarche • Nonwhite race • More longitudinal studies needed DP Williams 2007
Questions DP Williams 2007
References • Lee, JM, Appugliese, D, Kaciroti, N, Corwyn, RF, Bradley, RH, Lumeng, JC (2007) Weight Status in Young girls and the Onset of Puberty. Pediatrics 2007;119;E624-630. • McCartney, CR, et al (2007) Obesity and Sex Steroid Changes across Puberty: Evidence for marked Hyperandrogenemia in Pre-and Early Pubertal Obese Girls. J Clin Endocrin & Metab; 92(2):430-436. • Ribeiro, J, Santos, P, Duarte, J, & Mota, J. (2006) Association between overweight and early sexual maturation in Portuguese boys and girls. Ann Human Biology; 33(1): 55-63. • Slyper, AH. (2006). The pubertal timing controversy in the USA, and a review of possible causative factors for the advance in timing of onset of puberty. Clin Endocrinology; 65:1-8. DP Williams 2007