Obesity and Early Puberty

Pauline Williams, MPA, RD, CD

DP Williams 2007

Prevalence Overweight

0

10

20

Year

%O

verw

eig

ht

2-5

6-11

12-19

2-5 5 5 7.2 10.3 10.6 13.9

6-11 4.2 2 6.5 11.3 15.1 16.3 18.8

12-19 4.6 6.1 5 10.5 14.8 16.7 17.4

1963-65

1971-74

1976-80

1988-94

1999-2000

2001-02

2003-04

DP Williams 2007

Tanner Stage GirlsTanner Stage

Stage Development Pubic Hair Breasts

1 Early Adolescence

(10-13)

Preadolescent Preadolescent

2 Sparse, straight Small mound

3 Middle Adolescence

(12-14)

Dark, curl Bigger, no contour separation

4 Course, curly, abundant

Secondary mound of areola

5 Late Adolescence

(14-17)

Triangle, medial thigh

Nipple projects, areola part of breast

DP Williams 2007

Tanner Stage BoysTanner Stage

Stage Development Pubic Hair Penis/Testes

1 Early Adolescence

(10.5-14)

None Preadolescent

2 Scanty Slight increase/ Larger

3 Middle Adolescence

(12.5-15)

Darker, curl Longer/ Larger

4 Adult, course, curly Larger/ Scrotum dark

5 Late Adolescence

(14-16)

Adult, thighs Adult/ Adult

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

Year Age Tanner 2 Age Menarche

1940 11.0

1969 11.1-11.9 13.5

2002 9.5 African American

10.3 White

12.0 African American

12.5 White

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.