were obese by standards set in the mid-1960s (see Figure B). More fundamentally, why has the mean weight of all children in the United States risen over the past 20 or 30 years, causing the percentage of kids in the tails of the distribution to be obese?
Another area of population health in which we have acquired a great deal of evidence, Dr. Berkman said, is social stratification and inequality. For example, between 1969 and 1998, mortality rates dropped dramatically among men in every socioeconomic group. But those in the lower socioeconomic status groups had higher mortality rates, and the gap between the highest and lowest groups actually grew.
There are dramatic health disparities in racial and ethnic groups as well. In Table 1, which shows life expectancy for white men and women and black men and women from 1950 to 1996, life expectancy is improving for everyone. But as black men enter the 21st century they have a life expectancy less than what white men enjoyed 46 years earlier. Black women do only a little better—their rates look like those of white women 36 years earlier.