Cross-sectional association of dietary water intakes and sources, and adiposity: National Adult Nutrition Survey, the Republic of Ireland

Purpose: Drinking (plain) water intake has been associated with weight loss and reducing energy intake in intervention trials. In free-living populations, replacing other beverages with drinking water is associated with reduced obesity risk. However, the association of total water intake and its sources, and body fat distribution remain unevaluated. Thus, the aim of this study was to investigate total water intake and its sources and the association with anthropometric measures. 

Methods: Cross-sectional study of 1500 adults aged 18–90 years (Irish National Adult Nutrition Survey, 2008–2010). Total water intake and its sources were estimated using food records. Associations of total water, drinking water, beverage moisture and food moisture intakes split by tertile, and BMI (kg/m ² ), waist circumference (cm), and bio-impedance derived body fat (%) were evaluated using covariate-adjusted linear regression analyses including adjustment for energy intake and energy expenditure. 

Results: Higher consumption of total water was associated with lower waist circumference [β-coefficient (95% CI), p trend, tertile 3 versus tertile 1: − 2.19 (− 4.06, − 0.32), 0.036], but not BMI [− 0.44 (− 1.16, 0.28), 0.336] or body fat [− 0.87 (− 1.91, 0.17), 0.146]. Higher consumption of drinking water and food moisture were associated with lower BMI [− 0.65 (− 1.30, − 0.01), 0.027; − 0.64 (− 1.41, − 0.13), 0.014, respectively], body fat [− 1.51 (− 2.43, − 0.59), 0.001; − 1.00 (− 2.12, − 0.12), 0.001], and waist circumference [− 2.83 (− 4.51, − 1.16), < 0.001; − 1.84 (− 3.86, − 0.19), 0.082]. Beverage moisture was not associated with any of the anthropometric measurements. 

Conclusions: Consumption of drinking water and food moisture and not total water or beverage moisture were inversely associated with adiposity, independent of energy intake and expenditure. Advice encouraging drinking water and food moisture intake may be beneficial in addition to energy balance advice, in combating obesity.