June 8, 2008 Common misconceptions about drinking water Some people have a saying that the only thing that stays the same is change. This past week there have been two items that have changed from the standard way of doing things. The first is the weekly Tuesday night run from the Hays County Courthouse by the San Marcos Runners Club that members and other interested runners take part in at 6 p.m. in front of the building. After seven years of running every Tuesday at the Courthouse, runners were becoming increasingly aware of more and faster traffic at some of the intersections on the three-mile run in the historical district area. So after all this time, the Tuesday night run at 6:00 p.m. is still on, except that the starting point is at the Stagecoach Professional Center across from Hernandez Intermediate School. The runs offer less traffic, new routes, and for the serious runner a few challenging hills. Park in the lot nearest the street and everyone will run from there. The “everyone is welcome run” on Tuesdays at 6 p.m. is still around, except the change is in the starting point. The other change was in the news lately, and I read about it in the Nutrition Action magazine titled “In The Drink.” For years, the standard rule for drinking water was eight glasses every day for health benefits. Dr. Heinz Valtin, a physician and professor from the Department of Physiology Medical School, retired, is a widely respected authority on kidney function and water balance. It seems the origin of the theory started back in the 1940s by a board that made a rough rule of thumb that a person should drink one millimeter of water per calorie eaten. The recommended calorie intake was 2,000 calories, or roughly 2 liters of water to approximately two quarts. There was a second rule mentioned along with the eight glasses theory; and in the next sentence it stated, “and much of this can be gained from the solid food that we eat.” What wasn’t taken into account was the water people get from eating food. White bread is more than 30 percent water, but not many people eat bread to quench their thirst. People think that drinking coffee, tea or soft drinks does not count because of the caffeine and the diuretic affect it has on the body. That is only true if the amount is taken in large quantities, and normal amounts will not have that much of an effect and can be counted. He mentioned the increase of drinking bottled water, by people thinking it originates in clear mountain springs, is really being pushed by the companies that market it; but most of the water that is in the plastic bottles comes from the tap. He mentioned drinking water for health benefits is questionable in some studies, such as urinary tract infections, losing weight, and preventing constipation. In many cases drinking less than eight glasses has the same benefit as drinking eight glasses. He said if it works for you and you feel better for it, by all means continue. Dr. Valtin mentioned that the kidneys keep the water balance and blood concentration at the desired level without drinking large quantities of water. If a person drinks too much water, there is a symptom called water intoxication that results in the blood becoming diluted and the sodium balance is affected. When that happens, water moves to the cells and in the brain that causes a swelling of the brain cells and that can lead to serious consequences. One lady in California drank two gallons of water in a drinking water contest and died from the overdose of water. The one that I have written about and took as the standard of replenishing water from dehydration after a long run or a marathon was drink enough until your urine is clear. A corollary was that if you wait until you are thirsty it is too late. He said that the kidneys will conserve water and take care of that, and the color of your urine is not a good guide to judge by. He mentioned that it is a long way between a person feeling thirsty and dehydration. He did mention people in hot climates or who do vigorous exercise will need to consume more water than some others in temperate climates who lead a sedentary lifestyle. He recommends that five or six glasses will probably be enough; or drink if you are thirsty and with your meals. He says the blood concentration will be normal whether a person drinks 15 liters a day or only one or two liters. Aren’t kidneys a wonderful thing to keep track of that for you so you don’t have to count how many glasses a day you drink? Dr. Maurice Johnson - better known around San Marcos as “Moe” - is a professor in the Department of Health, P.E., Recreation and Dance at Texas State University - San Marcos. Moe has been a fixture in the San Marcos running community - both as a runner and race organizer - since way back when Moby Dick was a minnow. His column on running and fitness appears each Sunday in the Sports section of the San Marcos Daily Record. • Recent “Running With Moe” Columns • Home • About the Club • Current News • Club Runs • Places To Run • TX Running Clubs • Running Links • Useful Stuff Upcoming Races • Race Results • Country Roads 10K & Kids Run • ARA-Moe’s Better Half Marathon • “Running With Moe” Contact Us!