Our water needs depend on our general health, how active we are and the climate in which we live and play. We are about 60 percent water and we need to persistently replace the water we lose on a daily basis. The water we consume is needed to flush out toxic water-soluble chemicals from our organs, carry nutrients that we consume or as we metabolize them in cells, and to moisten the ears, nose and throat. We lose water all the time through breathing and perspiring which occurs more rapidly for those who are active, and/or living in an arid climate. We also lose water from urination or from bowel movements. Clearly, for those losing water at an enhanced rate for whatever reason, a greater rate of water consumption will be required to keep from being dehydrated. Insufficient water consumption can lead to dehydration, which can also lead rapidly to a feeling of weakness and general confusion.
An average male adult in a temperate climate will need about three liters of water a day whereas most women will require about 2.2 liters of water per day. Increased body size and exercise rate will mean that the above consumption rates should be increased. Three liters represents about 110 ounces of water or about 14 eight ounce glasses of water. This is about half as much as the suggested minimum consumption of eight eight-ounce glasses of water. Some have suggested eight eight-ounce glasses of water plus an additional eight ounce glass for every five pounds one is over weight. Also, we consume a moderate amount of water with our food, which is a lot for soups & broths and for heavily hydrated fruits and vegetables. There is some disagreement about whether con sumption of water with food should be counted. Nevertheless, some suggest that fruit juices as well as coffee, tea or other beverages should count as well, suggesting that consumption of water from food amounts to about 20-25 percent of the total water that we should consume. Thus, while it is easy to undercount just how much water you should be consuming, it is likely to be somewhere between two and three liters a day. This is at most about 0.2 liters or about 6-7 ounces per hour over a 16 hour day — or about 40 percent of a 17 oz bottle of water or about three quarters of an eight ounce glass per hour.
An easy test of whether you are getting enough water during the day is to look at your urine after going to the bathroom. If is is dark you are likely not getting enough water, if it is light yellow to colorless then your water consumption may be just about right. Thus, in the former case you will increase your water consumption rate, and for the latter continue drinking water at your current pace. If you are overweight and/or you exercise more than most, then you will need more water and should possibly be closer to the three liter mark than at two liters.
Many do not like the taste of tap water or filtered water alone or water from a plastic bottle. Try adding a slice of lemon, lime or an orange slice and a little ice. Get used to it. You are unlikely to overdose on water. Most of us get too little, in some cases far too litle rather than too much. Adequate amounts of water will aid digestion, improve your skin and connective tissue, reduce your tendency to overeat, keep your kidneys healthy and contribute to regular bowel movements reducing constipation. Adequate hydration helps the heart pump blood more effectively to get oxygen and essential nutrients to their intended destination in the tissues. Adequate hydration also energizes skeletal muscle and lessens the liklihood of experiencing cramps especially in the middle of the night. Through perhaps more complex mechanisms adequate hydration also protects the spinal cord and other sensitive tissues.
Adequate water intake, in addition to assisting the digestive process, will potentially accelerate metabolism especially when combined with eating less and eating more frequently. Smaller amounts of food 5-6 times a day should be consumed rather than larger amounts 1-3 times a day. In the latter case there is a danger of slowing metabolic rate. This is explained by some observers as the body interpreting your less frequent feedings as an attempt to starve it — the body then conserves energy by reducing basal metabloic rate.
Importantly, the elderly often have a poorly regulated thirst mechanism and may not sense that dehydration is coming on as easily as a younger person might. The older you are the more you should be watching for inadequate intake of water. Whether you are younger or older you can generally get by without sufficient water for a while but you won’t feel good. Potentially, you can feel faint and pass out at an inopportune moment. Many elderly fall and hurt themselves seriously. Not all such accidents come from fainting caused by dehydration, but likely some do and those can likely be prevented by adequate water intake. Thus, if you have a tendency to dehydrate then getting enough water will be hard to do at first. The benefits of good hydration will make it worth the trouble.
While I don’t intend to discuss all aspects of the problem of water availability here, high quality water may become increasingly hard to find. Suffice it to say, ground water contamination may be a problem in some locations. Aquafers are diappearing and remote lakes and rivers are not always as pristine as there were at one time. They may also contain parasites or contaminants of a more modern vintage. If you find that you are dependent suddenly, even if only for a while on a questionable water source, you may want to own one or more portable water filtration-purification systems. There are about 50 or so such systems for sale at http://www.moosejaw.com (see Camping Gear section under the heading “water filtration”). Theses systems are inexpensive and range in price from $10-150. The best are said to work by gravity filtration.