June 12, 2019

Quenching your thirst

Here’s what you need to know about hydration.

Contributed by Sean Hashmi, MD

When temperatures climb and sunny days prevail, the refrain “stay hydrated” is common.

But, do you know what that means? How can you tell if you need more water? And is water what you need?

To answer these questions and more, we turned to Sean Hashmi, MD, nephrologist at Kaiser Permanente in Southern California.

Is water the best for hydration?

All liquids count — even coffee and tea. Contrary to popular belief, these drinks, even when caffeinated, don’t dehydrate you easily. Studies have found it would take a lot to get you dehydrated.

Another myth is that you need to drink at least eight 8-ounce glasses of water. That’s not necessarily true, and while drinking water regularly throughout the day is a good idea, people may not realize that the majority of your water comes from food. There are water-rich foods such as watermelon and cucumbers that come to mind, but most fruits and vegetables are a natural source of water. Also, check out these cooling foods. Do drink more if you are eating processed foods because they don’t contain much water.

How much do I need to drink when it’s hot outside?

It’s very difficult to have a formula, but you do need more on hot days. One little test is to pinch your skin to see if it loses elasticity. But the best measure is just how you feel — are you thirsty? When in doubt, it’s better to have more fluids.

How can I tell if I’m well hydrated? How can I tell if I’m dehydrated?

Your body will allow you to know that it needs more or less fluids, so pay attention to what your body is trying to tell you. The most basic sign of needing more fluids is thirst. You can also check dryness in your mouth.

Another sign or measure of how well hydrated you are is urine color. A light color is ideal. If it’s dark yellow, you are starting to get dehydrated, and it’s really important to replenish. Also, if you need to urinate regularly, that’s a good sign, too. If you don’t urinate for hours, you probably need more fluids.

If adults feel dizzy or confused, that’s a sign of dehydration. If infants or toddlers don’t have wet diapers for 3 hours or seem listless, give them more fluids.

Older people, athletes, children, and those with chronic conditions have to be particularly careful because they don’t display the usual signs of needing fluids and then quickly become dehydrated — for instance, older adults (60 and older) often aren’t thirsty until they’re dehydrated.

If I’m dehydrated, what do I do? Just drink a lot?

Drinking more fluids and resting somewhere cool usually reverses dehydration, but severe dehydration needs immediate medical treatment because it can lead to serious consequences, such as heat stroke and kidney problems.

Are sports drinks helpful for hydration on hot days? 

In general, healthy people don’t need sports drinks or sugary drinks. That said, sometimes the electrolytes are necessary for certain groups of people who are more vulnerable to dehydration.

This summer, drink plenty of water, eat a diet rich in fruits and vegetables, listen to your body, and have fun.