Have been following this advice of gulping 8 glasses of water daily thinking that it’s good for us? Not exactly correct according to the research, published in the Proceedings of the National Academy of Sciences in the United States of America.
Actual amount of water needed depends person to person. Find what it does to our brain and body after reaching the hydration limit and how dangerous it is to ignore the simple feeling of over-drinking.
Drinking excess liquid activates a protective swallowing inhibition within the brain, study found. But forcing yourself to drink more than what your body needs overrides the mechanism and puts people at risk of potentially fatal condition called Hyponatremia, also known as water toxicity, scientists claim.
For the study, the researchers put 20 people in functional MRI (fMRI) scanners and asked them to rate the effort level required to swallow small amounts of water under two different conditions—after exercising, when they were thirsty; and later, after they’d already drank about a liter of water.
The results showed a three-fold increase in effort swallowing after over-drinking in both the cases. When the body is flooded with water, sodium levels can become abnormally low- a condition called Hyponatremia that can lead to lethargy, nausea, seizures, and even death. People who lose a lot of sodium through sweat and don’t replenish their levels (with salt or an electrolyte beverage) are especially at risk.
Of course, not drinking enough water is also a common problem in athletes, and in non-athletes as well. Mild dehydration may not lead directly to serious health problems, but it has been linked to low energy levels, headaches, constipation, and even obesity.
However, Lead researcher Dr Michael Farrell, from Monash University, Melbourne, said elderly people often don’t consume enough and should watch their intake of fluids.
If water enters the body more quickly than it can be removed then electrolytes in the blood become diluted. This causes the water to travel through the blood and pass into cells and organs such as the brain – affecting its ability to function.
So how much fluid should you get every day? The Institute of Medicine recommends that men aim for 125 ounces and women aim for 91 ounces a day, but that includes water from foods and other beverages—like juice, tea, and yes, even coffee—as well. That number can also vary based on your age, weight, other health conditions, and how active (and how sweaty) you are.
In short, says Farrell, don’t try to force anything. “Just drink according to thirst rather than an elaborate schedule,” he said. “If we just do what our body demands us to we’ll probably get it right.”