Water intakes and dietary sources of a nationally representative sample of Irish adults

Despite evidence that even mild dehydration is associated with various morbidities, water intake estimates in free-living populations are lacking. The present study aimed to estimate water intakes and dietary sources in a nationally representative sample of the Irish adult population.

A 4-day semi-weighed food record was used to collect dietary intake data from 1500 free-living adults aged 18-90 years in the Irish National Adult Nutrition Survey (NANS) (2008-2010) from which water intake was estimated. To enable fluid intake estimation, additional questions on how water and milk were consumed were incorporated. Total water intake was calculated as drinking water plus water from other beverages and food moisture.

The mean (SD) daily total water intake for Irish adults was 2.31 (0.92) L day(-1) [males 2.52 (1.00) L day(-1) ; females 2.09 (0.79) L day(-1)]. Intakes were lowest in elderly adults, as well as in those with less education, a lower social class, less energy expenditure and a higher body mass index and body fat percentage. In total, 67% of water came from beverages and 33% came from food moisture. Alcoholic beverages and teas individually contributed to total water intake in amounts similar to the drinking water contribution.

These data may be used as a foundation for further research in the area of the effect of under consumption of water on health outcomes to guide public health messages regarding adequate water intakes.