A new study reveals the myth of 8 glasses of water a day.
For those who find it difficult to drink the recommended eight glasses of water a day, we have good news: during the new study, it was found that this “rule” is not suitable for everyone.
Indeed, research shows that there is an easy way to find out exactly how much water you need to drink every day — just listen to your body.
Maybe this sounds pretty vague to you, but for the first time, researchers were able to provide scientific evidence that when people no longer need to drink water, it becomes physically difficult to swallow. As you can see, you still need to listen to your body, or rather, to the throat.
Scientists first discovered a mechanism that regulates fluid intake and does not allow us to drink excessive amounts of water, confirming the fact that everyone has different water needs.
“It’s better to listen to what your body tells you to drink when you are thirsty and not on schedule,” says lead researcher Michael Farrell from Monash University in Australia.
The good news is that even if you conscientiously drink eight glasses of water a day, it probably will not cause you any harm - some people may need to drink even more, but some may even have less.
It turns out that the feeling of thirst makes us understand when we need to drink water, but don't we feel that we have already drunk enough?
Excessive drinking of water is a real problem and a threat to health. Excessive fluid intake can lead to water intoxication - hyponatremia - lower sodium levels in the blood, which in turn can cause lethargy, nausea, and even more serious complications, up to seizures, coma, or even death.
But until now, no one has been able to figure out how the body regulates the use of water, and whether there is a special mechanism inside of us that prevents us from drinking too much water.
For their research, Farrell and his team asked 20 participants to estimate the amount of effort required to swallow water, first immediately after a debilitating workout, when they were very thirsty, and then some time after the workout, when rested participants did not feel thirsty.
Scientists have found that in the second case, three times more effort is needed to swallow water - this proved that the body still regulates its “saturation” with water - the swallowing reflex begins to be suppressed as soon as the body receives the necessary amount of water.
“We first found difficulty swallowing after excessive amounts of water, in other words, when participants did not want to drink, they had to overcome the body’s resistance,” says Farrell. "This is consistent with our view that the swallowing reflex is suppressed after a sufficient amount of fluid has already been drunk."
The Farrell team used functional magnetic resonance imaging to measure the activity of various parts of the brain just before the experiment participants drank water in one case, feeling thirsty after an intense workout, in the other at rest, without any desire to drink. Tomography recorded increased activity in the right prefrontal part of the brain, when participants drank through force without feeling thirsty.
This gave reason to say that the frontal cortex of the brain is activated, trying to overcome the reflex difficulty swallowing, so that participants drink the amount of water that was required during the experiment.
This study certainly has its limitations - it is a small number of participants, the swallowing reflex can be a purely subjective concept, the level of sodium in the blood can depend not only on excessive fluid intake.
But this is undoubtedly the first step towards the beginning of understanding how our body controls fluid intake, and it can help people make the right choice regarding the amount of water they drink - especially if they are having a hard time daily forcing themselves to drink the stated amount of water - 8 glasses a day.
“There were cases when marathon athletes were forced to drink a lot of water and they died at long distances. Of course, only in those cases where they blindly followed the recommendations of their coaches and drank a lot more than they needed, ”says Farrell.
But he also notes that older people often do not drink enough water, so they should especially watch this.
Currently, more research is needed to confirm the results and make sure that the reflex difficulty swallowing is the result of excessive fluid intake, but at the same time do not forget that water shortage is also dangerous for health, in any case, just listen your body. If it is really difficult for you to take at least one sip of water, then maybe this means something.