Hydration Basics: Staying Healthy in the Heat

The kids were wiped out after a long, hot July day at my sister-in-law’s new pool, and were easy to get to bed. As I do every night, before turning in myself, I checked on all the kids, starting with my seven-year-old. The creaky door must have woken her up. She sat up and croaked miserably, “So thirsty… water…” so I hurried downstairs and got her a nice cold glass of water. When I brought it back to her she gulped it down without stopping. Then, she flopped back onto the bed and fell asleep.

I did a mental review of the day and realized that I hadn’t been monitoring her water intake as closely as I usually do. As every parent knows, there’s a fine line between “I’m thirsty” and “I’ve gotta go.” She’s generally not very good at drinking water unprompted, and I realized it was likely that she hadn’t drank nearly enough water as she played all day in the hot sun. I vowed to do better.

How Do We Get Dehydrated, Anyway?

As temperatures rise, we all need to pay extra attention to staying hydrated and healthy. Sweating is one of the main ways we lose water, and is also a key cause of dehydration. Any water that is lost needs to be replaced, and if we don’t take in enough water to compensate, our bodies start to extract it first from muscle mass. At that point, we are well on our way to being dehydrated.

Most people’s bodies are good at avoiding dehydration. We (usually unconsciously) maintain adequate fluid levels by drinking liquids and eating food, which also contains varying amounts of water. However, during extreme heat and intense physical activity, we need to make sure we increase our water intake. Additionally, as I learned so clearly on that hot July day, children are at a higher risk of dehydration. The elderly and people on certain medications may also be at greater risk for dehydration.

What Are The Signs of Dehydration?

According to the National Institutes of Health, these are the key signs of dehydration to watch out for:

• Being thirsty
• Urinating less often than usual
• Dark-colored urine
• Dry skin
• Feeling tired
• Dizziness and fainting

The amount of water a person needs varies, depending on how much he or she loses throughout the day. Some people may be able to function fine with less water than other people are used to taking in each day.

The Centers for Disease Control and Prevention say that there are no strict guidelines on how much to drink, but recommend that we generally take in about three quarts of water (including water taken in via food) each day. If we are out in the hot sun, we need to drink much more.

Those who exercise regularly are already aware of how much extra water they need to drink in order to stay hydrated. The same goes for people who work outside, and have experience with the demands that heat and sunlight can make on their bodies.

Eight Glasses of Water a Day? Really?

So, under normal circumstances, do we need to be chugging eight glasses of water a day?

Most likely, no. There isn’t any good science that supports the “eight glasses” myth. In fact, drinking more water than our bodies need can be dangerous — overdoing hydration (hyponatremia) is a rare but real risk, and happens when we drink more water than our kidneys can process, which leads to dangerously low levels of sodium and other minerals in the blood. Research demonstrates that the vast majority of healthy people adequately meet their daily hydration needs by letting thirst be their guide.

Does Coffee Count?

Another common misconception is that our daily cup (or three) of coffee dehydrates us, and we need to drink water to counteract it. While it is true that caffeine is a diuretic (thereby robbing us of our precious water), it takes high quantities to achieve the diuretic effect. Studies have shown that coffee not only does not dehydrate you, it actually provides similar hydrating qualities to water. Coffee drinkers, rejoice!

There are certain drinks that we need to take a pass on when we need to make sure we’re staying hydrated. Beverages such as soda and beer should not be used to rehydrate. Under normal circumstances, drinking a soda or a beer is fine and won’t negatively affect your hydration levels. But when it’s hot out and you need to replace a lot of fluids, drink water.

So, stick to the hydration basics. Grab your favorite water bottle and make it your best friend this summer — as long as you listen to your body, and increase fluid intake during exercise or in high heat, you’ll stay hydrated and healthy!