Ever heard that you should drink 8 glasses of water a day?
When I was researching my book 10 Essentials of Highly Healthy People, I surveyed healthcare professionals about the essentials of being healthy.
A common reply was “drink plenty of water,” or “drink eight glasses of water per day.” However, when I began to research this recommendation, I could find no medical studies to back up this belief. So, I did not include it in the book.
Now comes a new study, which is the latest to undermine the belief advanced by some experts that we should each drink eight glasses of 8 ounces (225 ml) of water a day.
It turns out that a scientific review finds there is absolutely no evidence that people need to drink 8 glasses of water per day. According to the researchers, it’s not even clear where this advice (now a myth) got started.
In addition, there’s no evidence that weight loss is possible by drinking water (at least if you don’t eat better, sleep better, and exercise).
Another myth is that headaches are caused by water deprivation. However, there are no studies to suggest that this is true.
The last of the “four major myths” about drinking extra water is that it leads to more toxin excretion.
The bottom line is that if you’re thirsty, there no better drink that a glass of fresh water. But only when you’re thirsty.

Evidence wishy-washy for health benefits of water