Drinking water intake in the U.S.: What We Eat In America, NHANES 2005-2008

Authors: Sebastian, Rhonda; Enns, Cecilia; Goldman, Joseph

Submitted to: Worldwide Web Site: Food Surveys Research Group
Publication Type: Review Article
Publication Acceptance Date: 9/8/2011
Publication Date: 9/27/2011
Citation: Sebastian, R.S., Enns, C.W., Goldman, J.D. 2011. Drinking water intake in the U.S.: What We Eat In America, NHANES 2005-2008. Worldwide Web Site: Food Surveys Research Group. Available: www.ars.usda.gov/Services/docs.htm?docid=19476.

Interpretive Summary: Water, or moisture, is essential to human life. Plain drinking water provides about one-third of total water intake, which is a larger proportion than that provided by food or any other beverage group. Data on the intake of total plain drinking water and its subgroups, tap and bottled water, are crucial for many health-related analyses. Using combined nationwide data on dietary intakes from What We Eat In America (WWEIA), National Health and Nutrition Examination Survey (NHANES) 2005-2006 and WWEIA, NHANES 2007-2008, we examined intakes of total, tap, and bottled water by age and gender, identified differences in intake by gender, race/ethnicity, income, and activity level, and described patterns of plain drinking water consumption by location (at home and away from home) and eating occasion (meals and snacks). "Drinking Water Intake in the U.S.: What We Eat In America, NHANES 2005-2008," a Dietary Data Brief available on the Food Surveys Research Group Web site at www.ars.usda.gov/ba/bhnrc/fsrg, provides a snapshot of plain drinking water intake by individuals age 2 years and older. Findings include the following: Among individuals age 2 years and over, 76 percent drink some plain water on any given day, and the average daily intake of plain water is 3.9 cups per person (including both reporters and nonreporters); the majority of plain drinking water is consumed at home; about three-fourths of plain water (both tap and bottled) is consumed at snacks; the majority of plain water is consumed alone (i.e., at eating occasions with no other beverages or foods reported); physically active adults drink more plain water than sedentary adults; in some age groups, non-Hispanic whites have higher intakes of tap water than non-Hispanic blacks and Hispanics; and among adults, higher income is associated with higher intake of bottled water. By conveying this information through simple charts and brief text, this Dietary Data Brief widens the pool of users who can benefit from the Food Surveys Research Group’s ongoing work in monitoring and assessing food consumption and related behavior of the U.S. population. This information will be of benefit to legislators, program planners, media, educators, and consumers who want clear and easily comprehensible information about plain drinking water intake in the United States.

Technical Abstract: The goals of this study were to describe plain drinking water intake patterns of the U.S. population and determine whether total, tap, and bottled water intakes differ by gender, race/ethnicity, income, and activity level. Twenty-four-hour dietary recall data from 16,566 individuals age 2 years and over participating in What We Eat In America (WWEIA), the dietary intake component of the National Health and Nutrition Examination Survey (NHANES), in 2005-2008 were analyzed. Appropriate sample weights were applied to produce nationally representative estimates. T-tests were used to identify differences in intakes of total plain, tap, and bottled water intake by gender, race/ethnicity, activity level, and income. Regression procedures were used to adjust estimated means for confounding variables when testing for differences in daily plain water intake by race/ethnicity, activity level, and income. On any given day, 76 percent of individuals age 2 years and over report plain drinking water, and the mean intake per person (including both reporters and nonreporters) is 3.9 cups. Total plain drinking water intakes do not differ by gender within age group, but tap water intakes are higher for males 12-19 years than for females the same age and for females 60+ years than for males the same age (p<.001). The majority of plain drinking water is consumed at home. Nearly three-quarters of plain drinking water (both tap and bottled) is consumed at snacks, and over one-half is consumed at eating occasions for which no other food or beverage is reported. There are some differences in intakes by race/ethnicity, income, and activity level. In some age groups, including adults 20+ years, tap water intake is higher for non-Hispanic whites than for non-Hispanic blacks and Hispanics. Among adults 20+ years, there is a positive association between bottled water intake and income, though intakes of total plain and tap water do not differ by income. Adults who are physically active drink more plain water than sedentary adults do. The information furnished by this study is useful to anyone who is interested in plain drinking water in the U.S., including legislators, program planners, nutritionists, media, educators, and consumers.