We've become a nation of water drinkers, so bitten by the bug to imbibe that we lug bottles around all day, not only to stave off dehydration but also to avoid just about every other ill from dry skin to constipation to fatigue, muscle weakness and colds.
Are we desiccated or deluded? Obviously, since our bodies are two-thirds water, we need water to survive. But are most of us really getting too little?
Pop culture says so. Men's Health magazine extolled the wonders of water to achieve miracles like this: "Lose fat -- without pesky exercise!" Fereydoon Batmanghelidj, a Virginia physician who wrote "Your Body's Many Cries for Water," says water "cures many diseases like arthritis, angina, migraines, hypertension and asthma."
On the other side is Gary Curhan, a kidney specialist in Boston, who says that unless you have kidney stones, forcing yourself to drink water when you're not thirsty is silly.
In other words, if you eat regular meals and drink liquids as you eat, you're probably fine.
To help clear things up, here are:
FACTS AND MYTHS ABOUT WATER:
* How much do you need? On a sedentary day, to balance water lost through urination, breathing and sweating, you should consume half an ounce of water for every 2 pounds of body weight. If you're 120 pounds, that's 7 1/2 (8-ounce) cups.
How can you get this much? Easily, and not just by drinking. There's water in fruits, veggies and other foods. If you're still worried, keep water at your desk to sip.
* Do caffeinated beverages count? Sort of. Coffee, tea and caffeinated sodas are mild diuretics, making you urinate more. But they're basically water, so they help somewhat.
* What about sweet drinks and fruit juices? They count because they're mostly water. But the sweetness can make you thirsty -- and they're fattening.
* OK, how about beer (or other alcoholic drinks)? Beer is mostly water, too, but because alcohol is dehydrating, you can't count beer as hydration. That goes double for wine and liquor, which have so little volume they don't contain much water.
* Does drinking lots of water make you lose weight faster? Not directly. But filling up on water, plus fiber, can make you feel full, with few calories.
* Does water flush fat cells out of the body? Nope, sorry.
* Does extra water moisturize skin from within? No. All you need for your skin -- and other organs -- is basic hydration, says Richard Johnson, a Boston dermatologist.
* Does water fight constipation? Again, it's basic hydration that keeps things normal. Drinking excess water won't help. (If you have diarrhea, though, that's when you do need extra water. Some people make the mistake of trying to stop diarrhea by not drinking.)
* Can water rid you of excess mucus in your nose or throat? Mucus is made from water, so you need to be adequately hydrated to make it. But you can't make mucus thinner or a cough looser by drinking more.
* Is bottled water better for you than tap water? No.
* What about water needs during exercise? That's where you should take extra care, says the American College of Sports Medicine. When you exercise hard, especially in the heat, by the time you feel thirsty you're already dehydrated. It's sensible to drink some water before a long, vigorous workout. During exercise, if you sweat a lot, drink 8 ounces every 20 minutes. Afterward, drink several glasses, even a quart.
* Do you need to replace electrolytes after a sweaty workout? Not if you eat a normal diet.
* So there's no need for sports drinks like Gatorade? Probably not for workouts of less than an hour. Gatorade and similar drinks can provide energy during longer workouts and can help replace sodium and potassium lost through sweating. But if you do drink them, get those with 8 percent or less carbohydrate. Carbohydrates slow stomach-emptying, which means it takes longer to get water into your system.
* Does drinking water during hard exercise reduce fatigue? It seems to. Physiologist Edmund Burke of the University of Colorado in Colorado Springs studied skiers who either drank water only at lunch or sipped all day from a CamelBak portable water system. The sippers felt stronger and less tired, he says.
* Is it possible to drink too much water? Yes. Too much water dilutes the concentration of sodium in your blood and causes seizures and impaired thinking. But for most of us, it would take 15 quarts a day to cause this.
So what's the bottom line?
Do take dehydration seriously if you're elderly or exercising very hard. Beyond that, don't expect medical miracles from sipping all day. You probably don't need to force yourself to drink water.
Dehydration warning signs
Experts, self-appointed and otherwise, agree that actual dehydration can be deadly, not just for elderly folks who may lose a sense of thirst but for healthy young jocks, too. You may be dehydrated if:
* You are elderly and fall a lot (especially if you take diuretics, which make you lose water) and take anti-hypertensive drugs.
* Your urine is dark (vitamin supplements and other substances can also do this).
* You're not urinating as often as usual.
* Your mouth is dry.
* You weigh a couple of pounds less one morning than the day before.
* You get a low-grade headache after working out.
Pub Date: 6/21/98