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The recent decline in the height of African-American women
1Department of Economics, University of Munich, Ludwigstr. 33/IV, 80539 Munich, Germany. John.Komlos@gmx.de
Abstract:
Height trends since World War II are analyzed using the NHANES surveys for US-born individuals stratified by gender, ethnicity and income. After stagnating or declining for nearly a generation, the height of adult white men and women began to increase among the birth cohorts of ca. 1975-1986, who reached adulthood between 1995 and 2006. The increase in their height overcame the prior downturn that lasted between ca. 1965 and 1974. The height gap between white and black men has increased by 0.43cm (0.17in.) during past decade compared to the previous quarter century, to reach 1.0cm (0.39in.). In contrast to the three other groups examined, the height of black women has been actually declining by some 1.42cm (0.56in.). Consequently, a very considerable wedge has developed between black and white women's height of 1.95cm (0.77in.). In addition, black women in the age range 20-39 weigh some 9.5kg (21.0lb) more than their white counterparts. Two hypotheses are worth considering, namely, (a) that the decline in their height is related to the obesity epidemic and to inadequate dietary balance, and (b) that their future health will be subject to a double jeopardy in the sense that both their increasing weight and decreasing physical stature are likely associated with negative health consequences.
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