from 1 year of age in the United States were greater by 3 to 8 cm (≈ 1 to 2.5 in) than those of children of the same age in Canada measured two decades earlier (Demirjian, 1980). This difference could be partly explained by approximations necessary to compare the two data sets, but more likely by a continuation of the secular trend of increased heights for age noted in the Nutrition Canada Survey when it compared data from that survey with an earlier (1953) national Canadian survey (Pett and Ogilvie, 1956).
Similarly, median weights beyond age 1 year derived from the recent survey in the United States (NHANES III, 1988–1994) were also greater than those obtained from the older Canadian survey (Demirjian, 1980). Differences were greatest during adolescence, ranging from 10 to 17 percent higher. The differences probably reflect the secular trend of earlier onset of puberty (Herman-Giddens et al., 1997) rather than differences in populations. Calculations of BMI for young adults (e.g., a median of 22.6 for Canadian women compared with 22.8 for U.S. women) resulted in similar values, thus indicating greater concordance between the two surveys by adulthood.
The reference weights used in the previous DRI reports (IOM, 1997, 1998, 2000a, 2000b, 2001) were thus based on the most recent data set available from either country, with recognition that earlier surveys in Canada indicated shorter stature and lower weights during adolescence than did surveys in the United States.
COMA (Committee on Medical Aspects of Food Policy). 1991. Dietary Reference Values for Food Energy and Nutrients for the United Kingdom. Report on Health and Social Subjects, No. 41. London: HMSO.
Demirjian A. 1980. Anthropometry Report. Height, Weight, and Body Dimensions: A Report from Nutrition Canada. Ottawa: Minister of National Health and Welfare, Health and Promotion Directorate, Health Services and Promotion Branch.
DHHS (U.S. Department of Health and Human Services). 1996. Physical Activity and Health: A Report of the Surgeon General. Atlanta, GA: DHHS, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion.
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