The Importance of Hydration

If you’re concerned that you don’t always drink the “recommended” eight glasses of water a day, you can stop: No scientific evidence supports that often-cited number for adequate hydration. In fact, for most people, the Institute of Medicine (IOM) says you can simply let thirst be your guide.

As you get older, however, you might need to pay closer attention to your fluid intake. Older people often have a reduced sensation of thirst, so it’s easier to miss the warning signs that you’re dehydrating. (See What You Should Know for signs that signal dehydration.) Older bodies also tend to have lower fluid reserves, and seniors tend to underestimate how much water or other fluids they need to rehydrate after exercise or other causes of dehydration.

Fluid Facts

At any age, it’s important to stay hydrated—after all, water makes up about 60 percent of your body weight and 75 percent of your brain. Every cell in your body needs water to function. Water transports nutrients and oxygen throughout your body and carries away waste materials. It also lubricates your joints; getting enough water can help relieve the pain and stiffness of arthritis. Water also helps keep your digestive system functioning smoothly; inadequate water intake is a common cause of constipation. And, without enough water, your blood pressure may increase.

Your kidneys play a key role in regulating your body’s fluid balance, excreting excess water through urination. They function more efficiently when you’re well hydrated; dehydration stresses the kidneys and forces them to work harder.

Another way your body loses water is through its approximately 2.6 million sweat glands, which help regulate your body temperature. When your hypothalamus (an area of the brain) senses an increase in core temperature, it triggers increased blood flow to your skin, stimulating the sweat glands there and cooling your body through evaporation. Exercising can cause you to lose a quart of water or more in the form of sweat.

Your blood is mostly water, so when you start to get dehydrated, your blood volume decreases and your blood becomes thicker. Your heart then has to work harder to pump the thicker blood through your arteries and veins. Older people are less able to compensate for this increased blood thickness—another reason to be more aware of your body’s fluid demands as you get older.

Getting Enough

For women over age 50, the Adequate Intake (AI) of fluid—water from all food and beverage sources— is 2.7 liters (a little less than 3 quarts) a day, with about 9 cups coming from water and other beverages; the rest is usually obtained from food. You probably don’t think about food when you think of hydration, but the water in food does count toward your daily intake, typically contributing more than 20 percent of the average American’s fluid consumption. (See chart for more information about the water content of various foods.) For men over age 50, the AI is 3.7 liters (almost 4 quarts) a day, which includes about 13 cups from beverages including water.

Drinking water is the simplest and cheapest way to stay hydrated, but other beverages contribute, too. Researchers at the University of Nebraska’s Center for Human Nutrition have shown that the water in caffeinated beverages such as coffee and tea does contribute to keeping you hydrated. Studies found no significant difference in hydration benefits whether beverages were carbonated, diet, or contained caffeine. Even alcohol, in moderation, can contribute to total fluid intake, according to the IOM.

The share of Americans’ fluid intake coming from caloric beverages has sharply increased in recent years, however, and this increase has contributed to the obesity epidemic. Replacing sugary sodas and other sweetened beverages with plain water can keep you hydrated while also helping you maintain a healthy weight. In most areas, tap water is as healthy as bottled water and much cheaper.

If you don’t like the taste of water, add some berries, slices of citrus fruit, or fresh mint to liven up the flavor. Or, try flavored seltzer water, which is now available in a wide variety of flavors.

There are also many liquid water flavorings on the market. Products such as Crystal Light, Mio, Dasani Drops, and Propel have between 0 and 10 calories per serving, but they do contain additives. Use just enough flavoring to give the water a pleasant taste. Otherwise, you have an overly sweet beverage, since some sugar substitutes are 200 to 600 times sweeter than sugar.  

The post The Importance of Hydration appeared first on University Health News.

Read Original Article: The Importance of Hydration »

Powered by WPeMatico