How Much Water to Drink per Day?
Every living thing needs some water to survive, though animals such as humans and large mammals seem to need a lot more than other species. For example, research shows that the human body is mostly water – 60 percent or more. The question posed by the title focuses on how much “new” water a human being should drink each day to remain healthy, keeping the body’s systems operating correctly.
The required amount varies from one person to another, depending on age, amount of physical activity and overall health. It’s also important to drink more water if you live in a very dry, very hot climate, as the body will lose more moisture in these environments. (In addition to water that is needed to maintain moisture levels, the fluids of the body need water in adequate amounts to remove toxic substances and waste products out.
The body loses water when we breathe, when we sweat and when we urinate. It’s essential that we put fresh water back into the body by drinking clean water, juices and foods that have water in them. The Mayo Clinic reports that we need to replace more than six cups of fluid each day that is lost through urination alone. We might also lose another quart/liter of water each day through normal bodily functions. If we get some of this water back from our foods we still may need to drink as much as eight cups of water in a 24-hour period.
This is the basis for the recommendation that a normally healthy person should drink eight 8-ounce glasses of water in a 24-hour day. This amounts to about two liters or well over two quarts of water. Mayo Clinic reports state that this isn’t necessarily supported by scientific research but it could be a good guideline.
Other science research recommends more than 64 ounces of water. Some estimates use a three-liter level as the amount needed for an adult male, with 2.2 liters for a woman (Institute of Medicine). The Mayo Clinic says that a good guideline involves drinking enough water so we don’t feel thirsty, except for a few are moments during the day. We should also be able to produce “colorless or slightly yellow urine” in an amount close to 1.5 liters or 6.3 cups.
Factors that can certainly affect how much water is healthy or “right” for an individual include: how much exercise we get on a regular basis; whether we live in a very dry climate, such as the desert Southwest in the U.S. or locations in the eastern Mediterranean region; if we are suffering through an illness or injury; if a woman is pregnant or breast-feeding.
People who can’t or don’t want to drink the amount of water required to remain healthy can get fluids from fresh fruits (tomatoes and watermelon are especially good for this). Fruit juices that don’t have a lot of additives or sugar are also good sources for the water we need. Whatever the source, human beings need a significant amount of water each day to stay healthy and active.