“According to most of the literature, a safe general recommendation for daily fluid intake is about 3 liters of fluid (or 12 cups) each day. Since 1 liter (4 cups) comes from our food, this means that 2 liters (8 cups) comes from purposeful fluid intake (in other words, drinking).”
This is Precision Nutrition on Water and Fluid Balance. I read this and guffawed a bit. For me it presents a new way of looking at how much water a person should be drinking daily. Most could recite to you that they should be getting eight glasses of water a day. Here are the issues…
1) I have heard (and recited) that drinking “eight glasses” of water is ideal per day. Key word is glasses. How much is in a glass, you ask? Well, depends on the size of the glass. Could be eight ounces, 12 ounces, 16 ounces, etc. A person may have an eight-, 12- or 16-ounce glass but may not fill it up all the way.
2) We hear the number “eight” all the time. (That is technically meant to be “cups,” although you have all been referenced “glasses” before.) I understand that organizations and companies need to simplify messaging. But with no one ever hearing that the recommended total amount for fluid intake in a day is actually 12 cups (four cups of water being gained from food intake), we think eight is the only goal.
3) Four cups of our daily fluid are supposed to be taken in via food. No one knows this because the focus is always on the number eight. And, I consider that for water to be ascertained, we must also be eating the right foods. I’m sure the average Jane does not get close to four cups per day of fluid from eating canned, frozen, boxed, processed crap.
So… Revelation! The way I educate on hydration has forever changed. I will now be stating solidly 12 cups of fluid as the recommendation per day – four from nutritious food and eight from drinking water. Precise words matter. A whole picture matters. Relativity matters.