RT Journal Article
SR Electronic
T1 Inadequate Hydration, BMI, and Obesity Among US Adults: NHANES 2009–2012
JF The Annals of Family Medicine
JO Ann Fam Med
FD American Academy of Family Physicians
SP 320
OP 324
DO 10.1370/afm.1951
VO 14
IS 4
A1 Tammy Chang
A1 Nithin Ravi
A1 Melissa A. Plegue
A1 Kendrin R. Sonneville
A1 Matthew M. Davis
YR 2016
UL http://www.annfammed.org/content/14/4/320.abstract
AB PURPOSE Improving hydration is a strategy commonly used by clinicians to prevent overeating with the goal of promoting a healthy weight among patients. The relationship between weight status and hydration, however, is unclear. Our objective was to assess the relationship between inadequate hydration and BMI and inadequate hydration and obesity among adults in the United States.METHODS Our study used a nationally representative sample from the National Health and Nutrition Examination Survey (NHANES) 2009 to 2012, and included adults aged 18 to 64 years. The primary outcome of interest was body mass index (BMI), measured in continuous values and also categorized as obese (BMI ≥30) or not (BMI <30). Individuals with urine osmolality values of 800 mOsm/kg or greater were considered to be inadequately hydrated. Linear and logistic regressions were performed with continuous BMI and obesity status as the outcomes, respectively. Models were adjusted for known confounders including age, race/ethnicity, sex, and income-to-poverty ratio.RESULTS In this nationally representative sample (n = 9,528; weighted n = 193.7 million), 50.8% were women, 64.5% were non-Hispanic white, and the mean age was 41 years. Mean urine osmolality was 631.4 mOsm/kg (SD = 236.2 mOsm/kg); 32.6% of the sample was inadequately hydrated. In adjusted models, adults who were inadequately hydrated had higher BMIs (1.32 kg/m2; 95% CI, 0.85–1.79; P <.001) and higher odds of being obese (OR = 1.59; 95% CI, 1.35–1.88; P <.001) compared with hydrated adults.CONCLUSION We found a significant association between inadequate hydration and elevated BMI and inadequate hydration and obesity, even after controlling for confounders. This relationship has not previously been shown on a population level and suggests that water, an essential nutrient, may deserve greater focus in weight management research and clinical strategies.