be due to differences in survey methodologies, increase in estimated intake has occurred. In any case, mean intakes over this 40-year period, except for women in the first two survey periods, are in excess of the upper intake limit specified by the 2005 Dietary Guidelines for Americans.
As expected, dietary sodium intake density measures—meaning the number of milligrams sodium per 1,000 calories consumed—show that the intake differences expressed as milligrams disappear among children and adults on a sodium density basis, indicating the relationship between calorie intake and sodium intake (Figure S-3). As compared to a sodium intake density of < 1,150 mg/d per 1,000 calories needed to match the recommended intake of < 2,300 mg/d sodium (and assuming a 2,000-calorie reference diet), most groups had mean intakes that exceeded guideline levels, even during the earlier time periods when sodium densities appeared lower than in more recent years.
Moreover, trends in hypertension demonstrate an upward climb since the 1980s (Figure S-4). Although increased obesity rates may be associated with the increase among men, they do not explain all of the increase among women.
Past initiatives placed considerable, if not the primary, burden on the consumer to act to reduce sodium intake. These included educational and