This isn’t an easy question to answer. A part from the foot-long list of bodily functions mentioned in the previous article that need water for their efficacy, there are host of other functions your body does that also require water. Your lungs for instance, expel between two and four cups of water each day through normal breathing and even more on a cold day. If your feet sweat, there goes another cup of water. If you make half a dozen trips to the bathroom during the day, subtract six cups of water. Studies show that on average, on a typical day without exercise or exceedingly hot weather, we lose about 10 cups of water through perspiration, breathing, urination and bowel movements.
So it’s not rocket science to conclude that we have to consume plenty of water to replace these lots of fluids for our bodies to function at optimum capacity. But how much is enough? Again, this is not an easy question to answer. A healthy adult’s daily fluid intake can vary widely. Most adults need 8-12 cups of water each day. However there is no such thing as a standard, optimum quantity. The required fluid intake will vary from person to person, contingent on several factors, including how much you eat, how active you are, the climate you live in and your health status.
Start with one cup of water for every 250 calories you eat. If you consume 1,750 calories per day, you need to drink seven cups of water. But if you consume more than 2,250 calories, then aim to down nine cups a day.
Tack on an additional cup for every 30-45 minutes of moderate intensity workouts (e.g. walking or swimming ); two cups for high intensity like running or playing tennis. If you exercise for more than an hour at a clip, weight yourself pre and post exercise and for every pound you shed, add two and a half cups to your fluid intake.
Drink additional water in hot and humid weather to help lower your body temperature and to replace what you lose through sweating. And altitudes greater than 2,500 meters can also affect how much water your body needs. Higher altitudes may trigger increased urination and more rapid breathing, that uses up more of your fluid reserves.
Fever, vomiting and diarrhea cause your body to lose extra fluids. To replace these fluids, drink more water or oral rehydration solutions. Women who are pregnant or breast-feeding need additional water to stay hydrated and to replenish lost fluids, especially when nursing. The Institute of Medicine recommends that pregnant women drink 2.3 liters ( nearly 10 cups ) of fluids a day and women who breast-feed consume 3.1 liters which is about 13 cups of fluids a day.
Your curren total fluid intake is probably adequate if you do not feel thirsty and you produce a colorless or slightly pale, yellow urine. Strong smelling or dark urine could simply mean you are not drinking enough water and your urine is thus very concentrated. The same applies to skin odor. If you feel that a bad odor persists on your skin even after bathing, this is the result of an accumulation of toxins. Simply drink more water to aid in eliminating them from your system.
Do note however that thirst is not a reliable indicator of when to drink water. By the time you are thirsty, you are probably already mildly dehydrated. Besides, the older you are, the less likely you are to sense that you’re thirsty. And during vigorous exercise, an important amount of your fluid reserves may be lost before thirst kicks in.