Drinking Tea will not Make You Dehydrated

Caffeine-containing beverages such as coffee, coffee, etc., are often thought to cause dehydration because of the diuretic effect of caffeine.

In December 2015, Loughborough University (Loughborough University) in the United Kingdom developed a “hydration index” to measure the impact of beverages on body moisture after drinking them into the body. The principle of this index is that some liquids stay in the body longer than others and have a better hydrating effect. After all, if you drink a glass of water and quickly excrete half of the water in your urine, then you are actually only replenishing half of the water.

So, the scientists asked the subjects to cite 13 common beverages and measure the water content still in the body two hours later. And compare it with drinking pure water.

The results showed that electrolyte fluids, skimmed milk, whole milk and orange juice have a higher hydration index than water. The hydration index of tea, coffee, and carbonated beverages is the same as that of pure water.

In other words, drinking tea, like drinking water, can help the body replenish water without causing dehydration.

“Caffeine is indeed a diuretic, but the concentration of caffeine in most coffee drinks does not achieve this effect,” said Professor Moen of Loughborough University. “When we are thirsty, we drink normal tea, coffee or cola can Help us rehydrate. Very strong coffee or alcoholic beverages, such as distilled spirits, are exceptions.”

Nutritionists often use this “concept” to encourage everyone to drink “boiled water”, mentioning that drinking coffee and tea cannot replace water, but can drinking coffee and tea really cause diuresis and cause dehydration?

This time is to crack everyone’s illusion about coffee dehydration!

Caffeine does diuresis

Caffeine is an alkaloid substance that is a competitor of adenosine in the brain. It competes with adenosine for receptors on the nerves. Therefore, caffeine interferes with the original physiological functions of adenosine, such as: “Falling asleep” response and water balance.
Therefore, caffeine physiologically affects the kidney’s recovery of sodium ions and reduces the amount of water recovered by the kidneys, thus having a diuretic effect.

Some studies have pointed out that there will be obvious diuretic effects when ingesting more than 500 mg of caffeine per day. In the 2003 longitudinal study, 11 studies on caffeine and diuresis were collected, and pointed out that if there were no caffeine for several days to several weeks When you come into contact with caffeine, if you take a larger dose (250-300 mg, about 2 to 3 cups of coffee or 5 to 8 cups of tea) in a short period of time, you will have a diuretic phenomenon.

Another study also integrated the diuretic status of caffeine and related beverages in the past, and found that the results of each study are not the same, and it is difficult to conclude that “how much” caffeine intake will cause diuresis .