How Much Water Do You Need? Daily New Studies Challenge Old Rule

Do you really need to drink 8 eight-ounce glasses of water per day? The “rule” and recommendation for decades has been to drink 8 eight-ounce per day. But a more recent studies challenge that standard and offer more practical advice.

No clear definition for daily water requirements

According to a report released by the US National Library of Medicine and National Institutes of Health, “a clear definition of the daily water requirement needs does not exist.”

The report indicated that the total water consumption should be considered. That is, not solely considering water consumed by the body through drinking, but also factoring in water obtained through food and dietary nutrients, as well as, water produced by the metabolism.

Another study published by the American Journal of Physiology, said that the “8 x 8” rule (eight-ounce glasses of water per day) and many lay writings about it are akin to a “myth” that has been “discredited by scientific evidence.”

Their report also referenced the need to consider water consumed through solid foods and metabolism in contributing to a daily total of water intake.

Body composition

The body of an adult is composed of 60 percent water and is 75 percent at birth, according to the National Institutes of Health report. It’s the main component of cells, tissues, and body fluid components.

Consider your activity level

The study on water consumption by the American Journal of Physiology concluded:

“…have found no scientific proof that we must ‘drink at least eight glasses of water a day,’ nor proof, it must be admitted, that drinking less does absolutely no harm. However, the published data available to date strongly suggest that, with the exception of some diseases and special circumstances, such as strenuous physical activity, long airplane flights, and climate, we probably are currently drinking enough and possibly even more than enough.”

The report added that that sedentary adults following the 8 X 8 rule may be consuming “as much as one liter in excess” of their daily water needs.

Good general guidelines

Your body will naturally feel thirsty when your level of hydration is beginning to drop.

Simple guidelines: When you are thirsty – drink more water. When you are sweating – drink more water. When you are in warm or hot environments – drink more water.

Indicators in urine: You can also get visual feedback of your hydration level by observing your urine. When you are sufficiently hydrated, your urine should look very light yellow or clear. Dark yellow or orange urine usually is an indicator of dehydration (orange and dark urine can also be of blood in the urine).