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Lengthy Articles but good information for those of us that ride and live in desert areas. Enjoy. B) [/SIZE]
Stay hydrated and replenished
Susan Randolph, M.S., R.D.
Here they come! Family vacations, road trips, fun in the sun and … dehydration? There’s no faster way to ruin warm weather fun than feeling bad because you’re dehydrated. Staying healthy is easy if you know the signs of dehydration and how much to drink to avoid it.
Signs of dehydration
- Dry lips and tongue
- Headache
- Weakness, dizziness, or fatigue
- Lightheadedness
- Nausea
- Muscle cramps
- Darker urine than normal
People most at risk for dehydrationChildren: Kids lose water through their skin faster than adults.
Make sure: Your kids should drink 4–8 oz. of fluid before they go outside and 5–9 oz. every 20 minutes while they are outside. Once they come back inside, they should drink 24 oz. more, within the first two hours.
Athletes and exercisers: If you train and compete outside, you may not drink enough to make up for what you lose. Even short bouts of physical activity can increase your fluid needs.
Make sure: You drink 17–20 oz. before you start and an additional 7–10 oz. every 10 to 20 minutes that you’re active. And when you stop, your body still needs more: up to 24 oz. within the first two hours after you’re done.
Outdoor workers: You may not realize that working outside most of the day significantly increases your need for fluids.
Make sure: You should pack containers of water or other drinks in a cooler to take with you and take water breaks at least every two hours.
Older adults: If you’re an older adult, the heat will affect you more intensely – and your sensation of being thirsty is reduced. Dehydration is actually one of the most frequent causes of hospitalizations among people over the age of 65.
Make sure: If you are 65 or older, make it a point to drink every few hours, especially if you spend time outside.
So how much do you need?
There are at least three rules of thumb:
- Replacement approach. The average adult loses 8–10 cups a day under normal conditions. So, if you drink a little more than eight cups a day, along with your normal diet, you can replace what you lose.
- 8 x 8 rule. The thinking goes, if you drink eight 8-oz glasses of water a day, your basics are covered. And though this “rule” isn't supported by scientific evidence, it’s an easy guide to remember.
- Dietary recommendations. The Institute of Medicine recommends that men drink about 13 cups of fluids a day and women who are not pregnant or breastfeeding drink about 9 cups a day.
Alternatives to waterIf you don’t drink water because it tastes blah, or if you’ve lost electrolytes during exercise, a sports drink is a great option. Studies show that lightly sweetened, flavored, non-carbonated sports drinks do a better job than water of preventing dehydration. Sports drinks help to replace some of the electrolytes you lose through sweat, and they provide carbohydrate energy to working muscles.
Did you know?
Thirst is not always a good way to tell if you need to drink more. During vigorous exercise, your fluid reserves may be lost before you feel thirsty. So make sure that you're well hydrated before, during, and after exercise or exertion.
[SIZE=24pt]Water: 8X8[/SIZE]
Chester J. Zelasko, Ph.D. | June 24, 2008
Water has been in the news recently--drinking water, to be more specific. Two researchers from the University of Pennsylvania attempted to find the source of the long-standing recommendation to drink eight 8-ounce glasses of water per day or 8 x 8, for short (1). They saw that the Internet was full of recommendations for drinking a lot of water, and they wanted to find out why. They examined all clinical trials on drinking water back to the 1970s, and they couldn’t find a single clinical trial to support that recommendation!
Next they decided to examine some of the reasons that are given for drinking 8 x 8--their reasoning was that the recommendation had to be based on science. Let’s see what they found.
Clinical Outcomes
The researchers found four reasons cited on the Internet for drinking more water:
- Eliminate toxins
- Improve organ function
- Help weight loss
- Prevent headaches, including migraines
They couldn’t find significant research to support any of those claims. I agree, for the most part.
Drinking more water to flush the body won’t eliminate toxins--it just adds more fluid to the body. You eliminate toxins by providing the liver with proper nutrients so it can neutralize toxins and then eliminate them through the kidneys, but more water won’t help that process. The right foods and supplements will.
Drinking water before eating to help with weight loss proved to be equivocal. Some studies support it, others do not. I think that it comes down to being consistent. If you drink 8-16 ounces of water 15 minutes before every meal, that will give your body the water it needs and may help you eat a little less. As the researchers suggested, because water is not patentable, the research to prove or disprove it will never be done. I would try it anyway because there’s no harm and it’s a way of providing nutrients--and water is a nutrient--to the body on a regular basis.
Drinking water to help organs such as the skin or the brain also doesn’t have much basis in research. Severe dehydration can affect the skin, but drinking more water doesn’t provide additional benefits. The sparse research on drinking water for migraines did show improvement, but it wasn’t statistically significant. The brain is almost 80% water and the muscles about the same. Lack of water can cause fatigue and contributes to muscle cramps; it wouldn’t be surprising if drinking more water did benefit headaches, including migraines.
Is 8 x 8 Justified?
Let’s get back to the original question of the eight 8-ounce glasses of water per day. Is it justified? As I said, the researchers examined clinical trials back through the early 1970s, but perhaps they should have picked up a basic physiology textbook instead, such as
Guyton’s Textbook of Medical Physiology (2). If they had looked there, they would have found a section in the chapter on fluid balance that talked about how much water we lose every day under normal conditions:
- Skin (not from sweat)--12 ounces
- Lungs--12 ounces
- Sweat--4 ounces (without exercise)
- Feces--4 ounces
- Urine--48 ounces
- Total: 80 ounces per day. And remember, that’s without sweating due to exercise or high heat and humidity.
The recommended 8 x 8 would provide 64 ounces, and that means we would be 16 ounces short based on typical fluid loss, even before your daily exercise routine. That’s why eight 8-ounce glasses of fluid per day is still a good idea. Notice I said fluid. Tea, coffee, sports and energy drinks, soft drinks, juice--all fluids count toward that total.
The researchers focused only on drinking an additional 64 ounces of water per day. They picked a position and defended it from a strict clinical-outcome perspective. Normally that’s good practice, but in this case it just didn’t make any sense.
There’s one more thing that you’ll probably read somewhere and that’s the water in fruits and vegetables counts toward that total. I agree, but most of us eat only three or four servings of fruits and vegetables per day, if that. Let’s say you start your day with an orange; that’s four ounces of fluid. Later, with your dinner, you have a medium baked potato along with a cup of broccoli; that would add four ounces and three ounces respectively. Then let’s say you top it off with a banana--another three ounces. From the foods you ate, you got 14 ounces of water--you still need another 66 ounces. And that’s why eight 8-ounce glasses of fluid per day is still a good idea. Now you know why. Bottoms up!
References:
- Negoianu D, and Goldfarb, S. Just Add Water. J Am Soc Nephrol 2008; 19:1-3.
- Guyton and Hall. Textbook of Medical Physiology. 10th Edition. W.B. Saunders. Pps 264-5. 2000.
