With temperatures on the rise, staying hydrated is crucial. For many, water is their go-to hydration source—but what about other beverages? Do they have the power to keep us hydrated when the heat is on? Research says 'yes', finding that, over short-term periods, other beverages, like coffee, are just as hydrating as water. And some, like milk, may be more hydrating. Published in the American Journal of Clinical Nutrition, the study included 72 men in their mid-twenties who had fasted prior to the trial. At the beginning of the trial, the men were given 30 minutes to drink a liter of either plain water or one of the following beverages: oral rehydration solution (like Pedialyte), full-fat milk, skim milk, cola, diet cola, hot tea, iced tea, coffee, lager, orange juice, sparkling water, or a sports drink. Then, researchers collected the men’s urine for the next four hours to measure how much fluid remained in their bodies. This was used to assess how hydrating each drink was in comparison to water. After adjusting for each of the drinks water content, researchers found:

• After two hours, participants who drank the oral rehydration solution, full-fat milk, or skim milk retained more fluid in their bodies than those who drank water.
• After four hours, participants who drank cola, diet cola, hot tea, iced tea, coffee, lager, orange juice, sparkling water, or a sports drink retained the same amount of fluid in their bodies as those who drank water.

The fact that these beverages stayed in the men’s bodies as long as, or longer than, water indicates they may provide a satisfactory alternative to water, at least over short periods of time. Of course, it’s important to consider that some of these beverages contain many more calories than water, so they should be consumed in moderation. However, if you’re trying to avoid frequent bathroom breaks during a long road trip or business meeting, drinking milk rather than water could be a smart move.

Source: American Journal of Clinical Nutrition