I have enjoyed following astronaut Scott Kelly’s year in space on Twitter and I am glad he is safely home. So much will be learned about the effect of one year without gravity.
And for the first time in a year, Kelly will be drinking fresh water from the tap. That has to be better than the reclaimed wastewater from urine, hand washing and tooth brushing that is standard on the space station.
Even though water’s importance in maintaining health is well established, researchers continue to explore additional benefits. Two interesting studies came out last week. The first looked at hypohydration, defined as a 2 percent loss of water weight, in blood vessels of young, healthy males.
Hypohydration, which could occur before thirst is activated, had a negative effect on blood vessels as measured by flow mediated dilation. In fact, the reduction in flow mediated dilation was similar to what would happen after smoking a cigarette. Damage to the lining of the blood vessels is a contributor to heart disease.
The second study examined collected dietary data from the large nationwide NHANES Survey. Analyzing the food and drink habits of more than 18,300 adults, the survey’s results indicated that the majority of the people who increased their water consumption by 1 percent reduced their total daily calorie intake as well as intake of saturated fat, sugar and sodium. I was impressed that they consumed between 1-4 teaspoons less sugar and 68-205 fewer calories. Those numbers add up to a healthier intake.
The most frequent answer I hear when I ask my clients how much water they drink in a day is, “I know I don’t drink enough.” A simple strategy is to place a quart bottle on your desk and finish it by the end of the workday. Add cut fruit for flavor and a touch of nutrition. I am sure Commander Kelly is enjoying turning on the tap for a cool glass of pure water.
Sheah Rarback is a registered dietitian at the University of Miami Leonard M. Miller School of Medicine. Follow her @sheahrarback.