Jane M. Rees, MS, RD

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Food of the modern world Does it affect the
age of puberty?
Jane M. Rees, MS, RD Lecturer, Public Health
Pediatrics Maternal Child Health
Program University of Washington Seattle, WA.
U.S.A. Supported by
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From the Cover of Time Magazine, (Oct. 30, 2000)
Early Puberty Why Girls are Growing Up
Faster Is it hormones? Is it fat? Is it
something in the water? How parents and kids
are coping
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From an article in the New York Times Magazine
(Dec. 24, 2000)
The Making of an 8-Year-Old Woman How do we
understand early puberty? through the prism
of our time.
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From the New York Times
Article Two Endocrinology Groups Raise Doubt on
Earlier Onset of Girls Puberty (March 3,
2001) Letter to the editor Early Puberty in
Girls (February 24, 2001)
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New clinical study
Stage 2 or more 7.00 - 7.99 years
African-American European-American Breast
buds 15.4 5.0 Pubic hair 17.7
2.8 Herman - Giddens et al Pediatrics 1997
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Initial signs of puberty (female)
African-American European-American Previous
8 years 8 years New 6 years 7
years Kaplowitz et al Pediatrics 1999
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Recent history of menarche
1800 17.0 years 2000 12.5 years
Tanner, J Harvard U. Press, 1978 Adair
Gordon-Larsen A. J. Pub. Hlth., 2001
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Studies show
Body Weight - Menarche Heavy - Early Light
- Later
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Population based study overweight
Menarche ?11 a 11-13 a ?14 a European
American 36.4 22.4 22.3 African
American 57.5 36.4 37.5 Adair
Gordon-Larsen A. J. Pub. Hlth. 2001
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?

• Foods
• Pollutants
• Phytoestrogens
• Social

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Time Line
Angiosperm First Mammals
200,000,000 y
Homo Sapiens
100,000 y
Extinction of Dinosaurs
65,000,000 y
Today
Mammals flourished
10,000 y Agriculture
130 y Infant Formula
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Directional selection - corn
Source http//entmuseum9.ucr.edu/ent010jm/Evol.ht
ml
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Energy
Storage/Supply
Reproduction
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Frequency distribution of menarcheal age and age
at conception of a sample of African-American
adolescents (n574)
Rees JM, 2001 (unpublished)
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Fatness
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Accessibility
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Treats
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A Book Reference
Title The Botany of Desire A plants view of
the world by Michael Pollen Publisher Random
House Books, 2001
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Exchange of energy linked in brain
From Worthington, BS, Vermeersch, J, and
Williams, SR Nutrition pregnancy and lactation.
St Louis, CV Mosby, 1977. p 139.
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Feeding not linked to mother
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Intake not linked to output
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Rich food Excercise
Size
Advanced puberty
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Masculine puberty
Has it changed?
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Equivalent distance line
Angiosperm First Mammals
Homo Sapiens
1 Km
5 m
Extinction of Dinosaurs
325 m
Today
Mammals flourished
50 cm Agriculture
5 mm Infant Formula
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Future research
Will clarify the influence of modern foods on the
age of menarche
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The evidence
Change in foods has been dramatic