the NHANES Medical Examination Center (NCHS, 2009). Results were age-adjusted to the 2000 population.

The results show an increase from 1988–1994 to 2003–2006 for both men and women (NCHS, 2009). Similar trends were seen across race/ethnicity groups and different income levels. Using age-standardized data from NHANES 1988–1994 and 1999–2004, Cutler et al. (2008) reported a relative increase of 18 percent in hypertension prevalence rates (from 24.4 to 28.9 percent). None of the age/gender or race/ethnicity groups in their analyses had declining prevalence rates. After adjusting for changes in body mass index (BMI) over the two surveys, there continued to be large relative increases in the prevalence of hypertension for women. These results indicate that some of the increases of hypertension in women were attributable to factors other than increases in BMI. These factors may have included increases in sodium intake, changes in alcohol and potassium intake, decreases in physical activity, suboptimal health literacy levels, and lack of access to health-care services. For men, increases in BMI accounted for most of the increased prevalence of hypertension between surveys. Thus, after controlling for BMI, prevalences of hypertension between 1988–1994 and 1999–2004 remained relatively stable for men and increased for women.

In summary, the prevalence of hypertension in the U.S. population appears to be increasing. Controlling for the possible confounding effects of increasing body weight over the same time suggests that the prevalence is stable for men but increasing for women, even after controlling for obesity. However, neither the stable prevalence pattern seen for men nor the increasing pattern seen for women is consistent with a declining pattern of hypertension prevalence that would be expected to be associated with significant reductions in sodium intake on a population-wide basis.

From the descriptions in this chapter, it is clear that a myriad of sodium reduction strategies, programs, and initiatives have been implemented by numerous government agencies, health professional organizations, and the food industry—starting in 1969 and continuing to the present. These programs had common themes and a consistent message on the relationship between sodium intake and hypertension, with special emphasis on consumer education, sodium labeling of food products at point of purchase, and encouragement of reformulation by food processors and more recently by restaurant/foodservice operators. Audiences for these programs and initiatives included consumers, health professionals, the media, and the food industry.

To assess whether relevant population- and industry-based changes occurred during the 40 years since the first strategies, programs, and ini-