dens et al., 1997), rather than differences in populations. Calculations of BMI for young adults (for example, a median of 22.6 for Canadian women compared to 22.8 for American women) resulted in similar values, indicating that by adulthood there was greater concordance between the two surveys.

The reference weights chosen for this report were based on the most recent data set available from either country, recognizing that earlier surveys in Canada indicated shorter stature and lower weights during adolescence compared to those from surveys in the United States.

Reference weights are used primarily when setting the EAR, AI, or UL for children or when relating the nutrient needs of adults to body weight. For the 4- to 8-year-old age group, it can be assumed that a small 4-year-old child will require less than the EAR and that a large 8-year-old will require more than the EAR. However, the RDA should meet the needs of both.

Dietary Reference Intakes is a generic term for a set of nutrient reference values that includes Estimated Average Requirement, Recommended Dietary Allowance, Adequate Intake, and Tolerable Upper Intake Level. These reference values are being developed for life stage and gender groups in a joint U.S.-Canadian activity. This report, which is the first in a series, covers the DRIs for calcium and four related nutrients: phosphorus, magnesium, vitamin D, and fluoride.