Adhering to a drinking regime has its health reasons, but each individual needs to drink a different amount of water. Previously, about two liters of water per day for an adult was considered the optimal amount. A study published in the Science journal says that we don’t need to drink that much water. Water is contained elsewhere than just in a glass or bottle.

How Much Water to Drink Per Day?

The recommendation to drink eight glasses of water daily has become widely accepted. It often appears in health guidelines, despite the fact that this recommendation is not scientifically supported. “Most scientists are not even sure where this recommendation came from,” said Josuke Yamada of the National Institute of Biomedical Innovation, Health and Nutrition in Japan and one of the lead authors of the study

Most people probably don’t need to drink eight glasses, i.e., about two liters of water daily. A new study published in The Science shows that the average adult needs about 1.5 to 1.8 liters of water per day. Most people also get water from food.

Water in Food

Previous estimates of water needs have typically ignored the water content of food, which can be a substantial part of total intake. According to Yamada, if a person only eats pastries, sausages, and eggs, he will not get much liquid from the food. But if his diet includes vegetables, fruits, meat, rice, and pasta, he can get about fifty percent of his water needs from food.

This study shows that the previously accepted recommendation that everyone should drink eight glasses of water, or about two liters a day, is probably too much for most people in most situations. Moreover, referral leads to waste. For example, if British residents were to follow the recommendation, it could lead to about twenty million liters of drinking water being wasted every day.

Although drinking more water than the body needs is probably not harmful to health, producing clean drinking water is financially and environmentally demanding. There are opinions that the bottled water industry causes the drinking regime trend.

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