Researchers Are Clear: Water Is Not the Most Hydrating Drink

Researchers Are Clear: Water Is Not the Most Hydrating Drink

We know that we need to drink regularly to stay healthy and in good shape. But is water really the best drink to hydrate yourself? Researchers have investigated this question.

Summer is here, and so is the heat! With temperatures over 35°C, it's essential to stay hydrated. Our body is 65% water, which hydrates cells, provides minerals, eliminates waste, and maintains temperature. We constantly lose water through urine, feces, breath, and sweat, so it's crucial to replenish it even if we don't feel thirsty.

Contrary to expectations, water is not the most hydrating drink. A 2016 study in The American Journal of Clinical Nutrition on 72 individuals reveals that other beverages hydrate better.

Researchers divided participants into two groups: one drank 1 liter of water in 30 minutes, and the other drank 1 liter of another beverage. They analyzed the speed and duration of hydration. Surprisingly, among the thirteen liquids studied, water was not the most hydrating. Our body responds to both the volume and nutrients in the drink.

"Plain water hydrates quickly but doesn't keep us hydrated for long. Drinks with a small amount of sugar, fat, or protein retain liquid in the stomach longer before being absorbed and expelled," the researchers explain.

Here is the ranking of beverages according to their "hydration index", from most to least hydrating:

  • Skim milk (skimmed milk) 
  • Rehydration solutions (medications for dehydration)
  • Whole milk
  • Orange juice
  • Coca-Cola
  • Diet Coke (now replaced by Coke Zero)
  • Iced black tea
  • Hot black tea
  • Sports drinks like Powerade
  • Plain water
  • Sparkling water
  • Lager beer (low alcohol beers)
  • Hot black coffee

Skim milk ranks as the most hydrating drink. It contains electrolytes, such as sodium and potassium, which help retain water in the body and promote better absorption. In second place are oral rehydration solutions, powdered preparations that, when mixed with water, quickly rehydrate babies with diarrhea.

Nonetheless, water is obviously the preferred drink for healthy hydration, because it has no calories, unlike these other drinks. Remember not to wait until you're thirsty to drink. It's better to drink small amounts throughout the day and increase your intake in hot weather, during fever, or with physical exercise. Also, watch out for the caloric and sugar content of other types of drinks to maintain good health.