Wonderful Water

October 5, 2004

by Laura Dolson

We are bags of water. Or, more accurately, we are mostly a collection of tiny bags of water known as cells.

We are constantly losing water. It goes into the toilet. It gets sweated off. When we "see our breath" or on a cold morning, or fog a mirror with our breathing, we can see that we lose water with every breath we take. We need to replace water continually - we can live much longer without food than without water.

How much water do we need? You will hear all kinds of different recommendations about much much to drink, from 8 glasses of water per day or more, to "let your thirst be your guide". There are facts in favor of both of these approaches, but actually the amount of needed water varies for each individual on different days according to body type, activity level, temperature, and other factors. For most people in most circumstances, thirst is probably a good guide, BUT

- Some people are probably more attuned to mild thirst sensations than others.

- It's fairly easy to get busy and ignore thirst until it gets extreme. Being a bit underhydrated can leave us feeling not at our best - sluggish, a bit weak, or having difficulty concentrating. More severe dehydration can cause more serious weakness (even fainting), dizziness, confusion, etc.

- When we exercise, or when the temperature is higher, we need more water. It's important to drink extra before, during and after exercise.

- Illness often brings increased needs for water. (You really should "force fluids" during colds and fevers.)

How can we get enough water? Any fluid, of course, is mostly water, so it all "counts" towards your daily intake. Drinks with caffeine do cause us to urinate more (caffeine is a diuretic) but most of the fluid in them still gets used by the body. Alcoholic drinks have a much stronger diuretic effect, and can leave the body dehydrated.

If you eat a lot of fresh food, you won't have to drink as much. Since all living things are "bags of water", fruits, vegetables and meats can fill part of our water needs. I analyzed a day of eating recently and found that I had eaten over a quart of water in the course of the day.

Tap vs Bottle - So many people are carrying bottles of water around that it's easy to reach the conclusion that it's better for you to do so. Let's look at some facts:

Tap water - For most people in this country, tap water is quite safe. In the San Lorenzo Valley, we are particularly lucky. We have a water source that is close by in our very own mountains. Compare this to most of the Bay Area, which brings its water in from Yosemite. From November to May, our water comes almost straight from the sky due to our heavy winter rainfall. The rest of the time, our water is a combination of surface water and well water. All of our water is tested for safety and treated as necessary. The government establishes safe levels of substances which can affect health, and testing shows that our water is within these limits, and usually considerably under them.

Bottled water is convenient, but did you know that between 25-40% of bottled water comes from tap water? Some of it is treated further and some isn't, and different states have different regulations for how pure it must be. In many states, there are fewer rules about the purity of bottled water. In California, the rules are similar for bottled water vs tap water. When tested, often bottled water is similar to tap water is terms of levels of contaminants. Sometimes it is better - but occasionally it is worse.

Bottled water can also be a source of bacterial contamination if not used properly. Once the bottle has been opened, bacteria can enter, especially when drinking directly from the bottle. Tiny food particles and unwashed hands add to the problem. Leave the bottle in the sun for awhile and you're on your way to having your own "ecosystem in a bottle"!

Likewise, don't reuse bottles unless they have been washed and thoroughly dried between uses. Even then, the bottles water is sold in are meant to be temporary, and will begin to break down with heat and sun exposure. It's better to buy a wide-mouth, easily cleaned bottle meant for multiple uses.

Questions For Discussion:

Think of some of the pros and cons of using tap water vs bottled water. Write them down if you wish, as we will discuss them in class.

Do you like drinking plain water? Can you think of ways to make it more likely that you would drink water?