If you can teach yourself to drink ordinary tap water when you’re thirsty, and avoid juices and soft drinks, you’ll find it much easier to reach and maintain a healthy weight. Every glass of water you drink each day is worth nearly 70 kilocalories the American epidemiologists Rupeng An and Jennifer McCaffrey calculated.
An and McCaffrey used data on 18,311 American adults who had been followed from 2005 to 2012 during the National Health and Nutrition Examination Survey. They looked at how the participants’ diet changed if they started to drink more water instead of other drinks.
With every glass of water that the Americans drank daily their diet improved. An and McCaffrey were able to calculate that for every glass of water that the participants drank instead of a different drink their total energy intake decreased by 69 kilocalories. And most of those calories were in the form of sugars.
That’s partly because water is a substitute for soft drinks, but it’s not the whole story. Changing to water as a thirst quencher also leads to a reduction in the consumption of other less healthy foods – like the so-called discretionary foods.
This is a collective name for products with little nutritional value, such as “cookies, pies, ice cream, confectionery, chocolate, other desserts (e.g. custards, puddings, mousse), sweet rolls, waffles, cakes, pastries (e.g., crepes, cream puffs, strudels, croissants, muffins, sweet breads), biscuits, hush puppies, chips, popcorn, pretzels, party mixes, and fries.”
“In conclusion, the present study examined plain water consumption in relation to energy/nutrient intake and diet quality among US adults using nationally representative data,” the researchers wrote. “An increase in the proportion of daily plain water in total dietary water consumption was found to be associated with a decreased daily intake of total energy […].”
“Promoting plain water intake could be a useful public health strategy for reducing energy and targeted nutrient consumption in US adults, which warrants confirmation in future controlled interventions.”
Plain water consumption in relation to energy intake and diet quality among US adults
The present study examined plain water consumption in relation to energy intake and diet quality among US adults.
A nationally representative sample of 18 311 adults aged ≥18 years, from the National Health and Nutrition Examination Survey 2005–2012, was analysed. The first-difference estimator approach addressed confounding bias from time-invariant unobservables (e.g. eating habits, taste preferences) by using within-individual variations in diet and plain water consumption between two nonconsecutive 24-h dietary recalls.
One percentage point increase in the proportion of daily plain water in total dietary water consumption was associated with a reduction in mean (95% confidence interval) daily total energy intake of 8.58 (7.87–9.29) kcal, energy intake from sugar-sweetened beverages of 1.43 (1.27–1.59) kcal, energy intake from discretionary foods of 0.88 (0.44–1.32) kcal, total fat intake of 0.21 (0.17–0.25) g, saturated fat intake of 0.07 (0.06–0.09) g, sugar intake of 0.74 (0.67–0.82) g, sodium intake of 9.80 (8.20–11.39) mg and cholesterol intake of 0.88 (0.64–1.13) g. The effects of plain water intake on diet were similar across race/ethnicity, education attainment, income level and body weight status, whereas they were larger among males and young/middle-aged adults than among females and older adults, respectively. Daily overall diet quality measured by the Healthy Eating Index-2010 was not found to be associated with the proportion of daily plain water in total dietary water consumption.
Promoting plain water intake could be a useful public health strategy for reducing energy and targeted nutrient consumption in US adults, which warrants confirmation in future controlled interventions.