We already knew that you shouldn’t drink soda (even with ice cubes!) when you’re thirsty, because they promote dehydration, which can even lead to kidney dysfunction. But researchers from the University of St Andrews, Scotland, sought to find out which drink had the best hydration power.
For this, they studied the effects on the body of 13 common drinks, calculating both the water balance of the body (so-called water balance) and the volume of urine, because a drink can perfectly quench thirst but be diuretic. All these calculations then enabled them to assign a hydration index to each drink.
How do you know if a drink is hydrating?
For this study, published in the American journal of clinical nutrition72 men (all physically active and aged between 18 and 35) drank either 1 liter of plain water or 1 liter of another beverage (cola, sports drink, beer, black coffee, orange juice, milk, black tea, etc.) over a 30-minute period . Their urine was then collected for the following 4 hours, in order to measure the diuretic effects of the drinks ingested. They also measured the amount of water retained by the body 2 hours after ingestion.
Conclusion: Whole milk, skimmed milk, sports rehydration solution and orange juice have a higher hydration index than plain water. The researchers concluded that drinks that contain a little sugar, fat and protein are the most hydrating. In other words : drinking a glass of milk would be more hydrating than drinking a glass of water.
Which drink is the least hydrating?
In the last position of this classification, we find coffee, which is hardly surprising because of its diuretic effects. However, scientists point out that this study only looks at the immediate effects of drinking beverages. “Any subsequent ingestion of food or liquid negates the effects of the initial drink,” they add, explaining that they observed no significant difference in the effect of the various drinks on hydration status when consumed. over 24 hours.
In other words, you can continue to drink water throughout the day: it’s good for your health!
Source : A randomized trial to assess the potential of different beverages to affect hydration status: development of a beverage hydration indexAmerican journal of clinical nutrition, March 2016
