This is a simple question that I am asked frequently. The answer is: “It depends.” I’m sure most people have heard the rule to drink at least 8 glasses with 8 ounces of water a day. It is commonly expressed as the standard amount of water to drink. It depends on several things including your overall health, where you live, and what you are doing.
Water makes up about 60% of your body and is needed in every cell. Slight dehydration can zap your energy away. We can survive a long time with little or no food, but we must have water. Water is essential in flushing out toxins, transporting nutrients, and moisturizing our airways, skin, and joints.
The Institute of Medicine has published its recommendations. They have said that the average man needs about 13 cups (3L) of water a day and the average woman needs about 9 cups a day (2.2L).
There are several factors that can influence the amount of water you need. Moderate exercise may require another 1–2 cups of water. Extreme heat can increase your water demands. Illness such as vomiting or diarrhea increases water demands as well. Some health problems such as congestive heart problems or some types of kidney problems may require you to even consume less water.
Extreme sports such as running a marathon require close monitoring of your fluids and electrolytes. The electrolytes are basically minerals that your body needs to function correctly. A rare but potentially fatal problem for some marathon runners is hyponatremia. This is caused when someone has too much water and not enough sodium. It can lead to heart arrhythmias.
A practical way to monitor your hydration status is to monitor your urine output. You could actually measure the amount and it should be around 1.5 liters a day. A more practical way is to monitor the color of your urine. It should be clear or light straw colored. Darker urine may signify dehydration.
Water is in many things. On average, the food we eat accounts for about 20% of our water intake. Water is in milk, coffee, and other beverages. Some fruits such as watermelon are about 90% water by weight. We can get our daily requirement of water from several sources. Stay hydrated and you should feel a little better and will avoid some future problems.