When you hear the word “dehydration,” it’s easy to picture someone crawling across hot desert sand with an empty canteen and no hope in sight. But you might not think about the confused elderly person, the fussy toddler who’s not shedding tears even though they’re crying or those times when you were tired, headachy and very thirsty. This is what dehydration looks like in the real world. But you can beat dehydration before it gets to the point where you experience the worst of it.
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Emergency medicine physician Baruch Fertel, MD, and pediatrician Paula Sabella, MD, break down the warning signs of dehydration and give some tips for staying safe when the temperature rises.
What is dehydration and what causes it?
Dehydration occurs when your body loses more fluids than it takes in. When you’re dehydrated, your body can’t function as intended. While you might associate dehydration with extreme temperatures, there are quite a few things that can contribute to it.
Dehydration causes include:
- Excessive sweating.
- Continuous vomiting or diarrhea.
- Frequent urination.
Who’s more at risk for body dehydration?
Since dehydration can be caused by illness or being in extreme heat, any of us can be susceptible to it. However, there are a few populations that are at a slightly higher risk.
- If you work outdoors, the CDC recommends hydrating before you start the work day if you’re working in high temperatures. If you start the work day dehydrated, it might be harder to replenish what your body has lost.
- Being an older adult. Older people may be at higher risk for dehydration because your body’s fluid reserves decrease as you age. Your body also gets to the point where it might not effectively communicate thirst.
- Infants and toddlers are at risk because they can’t tell you when they’re thirsty. Dehydration can also develop when they’re sick.
- If you have a chronic condition, you might be more susceptible to dehydration, especially if you’re living with a digestive condition that causes frequent diarrhea. Medications can also cause dehydration if they have diuretics in them.
- If you’re pregnant, hyperemesis gravidarum (HG) can cause severe vomiting and make it tough to keep fluids down. In some cases, you might require IV fluids to prevent dehydration.
- If you’re an athlete, it doesn’t matter if you’re outside, indoors or even in water, athletes can become dehydrated in any setting. When you’re engaged in intense physical activity, your body temperature rises. Sweat cools your body down, but you lose fluids and electrolytes in the process. You can become dehydrated if both aren’t replenished.
Signs of dehydration and what we can do to prevent them
After being cooped up for so long, many of us are trying to make the most of our summer — even in higher temperatures. However, to prevent dehydration or even heat stroke, Dr. Fertel says we need to stay hydrated.
“The most important thing someone can do to prevent themselves from experiencing a heat-related illness is to stay hydrated. It’s really important, especially now that it’s getting extremely hot outside.”
Dr. Fertel shares a few symptoms to look out for.
“When someone is dehydrated, they’ll experience intense thirst. They also might not urinate frequently. Those are signs that you’re not getting enough fluids and progressing to dehydration. As you’re out in the heat more, you may feel warm to the touch and stop sweating. What you’re experiencing can progress to heat stroke. And by this point, you might have an altered mental status or not act right.”
Once you recognize that someone is dehydrated, Dr. Fertel recommends getting them out of the heat and giving them plenty of fluids. And by fluids, he strongly recommends leaving the booze alone.
“When we talk about hydration, it’s really important to drink water or other non-alcoholic liquids, as alcohol can actually exacerbate dehydration. It can be a diuretic and cause you to urinate more.”
Additional signs of dehydration
Dr. Fertel touched on intense thirst, not urinating as much, your skin being warm to the touch and not producing sweat as symptoms of dehydration. Here are some other signs of dehydration to look out for:
- Being cranky or anxious.
- Headache, delirium, confusion.
- Dry mouth and/or a dry cough.
- High heart rate with low blood pressure.
- Not being hungry but possibly craving sugar.
- Flushed skin.
- Swelling in the feet.
- Muscle cramping.
- Heat intolerance, or chills.
- Urine that is darker in color (not light or clear).
If someone is confused, fainting, not urinating or in shock, get help immediately. The same also goes for heavy breathing or a rapid heartbeat.
How to prevent dehydration while working in high temperatures
It’s best to be proactive about staying hydrated if you work outside. You don’t want to just guzzle water once you’re on the job. Drink water before you start working and before you even feel thirsty. Once you’re in the heat, drink one cup of water (8 fluid ounces) every 15 to 20 minutes. Avoid drinking more than 48 ounces of water or sports drinks in an hour because doing so might cause the amount of salt in your blood to drop too low. And hydrate after work to replace what you might have lost from sweating.
When is it too hot for kids to play outside?
Kids live for this time of the year. They get to rip and run with their friends all day or play their favorite summer league sports. Of course, we want them to enjoy every minute after the craziness of last summer. But where do we draw the line when it comes to playing outside in the heat?
Dr. Sabella says while we have every reason to be cautious, we should still weigh hot-weather scenarios on a case-by-case basis.
“There are some recommendations that children should not play outside when the heat index reaches 90 degrees F. This is certainly an important recommendation, but it’s good to consider the specific circumstances when determining if it’s safe for your child to go out and play. For example, let’s look at two children on the same soccer team playing a game on a hot day. If one child hydrates the night before, hydrates during the game, takes breaks and continues to hydrate after the activity, this child is in a much safer situation as compared to a child who didn’t hydrate properly.”
How to prevent dehydration in children
Dr. Sabella says that hydration is important for everyone on those hot and muggy days.
“For older children and teenagers, water remains the preferred drink for hydration. Teens can drink sports drinks to restore electrolytes they might have lost through excessive sweating and exercise. After a significant amount of vigorous exercise (about an hour or so), it’s OK to drink sports drinks in conjunction with water to recover.”
Dr. Sabella says breast milk or formula is a good source of hydration for infants. She strongly recommends not giving infants water or diluting formula with it.
How to tell if a baby or toddler is dehydrated
Identifying dehydration with kids, especially babies and toddlers, requires a little more investigation. While small children can’t express that they’re thirsty with words, their behaviors can reveal how they’re feeling.
Clues of dehydration in infants and young children:
- They’re less playful and sleepier.
- They can be more irritable than usual.
- The soft spot on their head is sunken in.
- There’s a decrease in wet diapers.
- Fewer or no tears when crying.
“With infants, the clues to dehydration may be subtle. However, if you notice any of the signs, contact your child’s healthcare provider right away.”
How to tell if an older child is dehydrated
Older kids tend to show more of the familiar symptoms of dehydration than younger children do.
Signs of dehydration in older children include:
- Dry mouth or cracked lips.
- Dark or concentrated urine.
- A decrease in urination.
- Flushed skin, or skin that feels dry or warm to the touch.
- Dizziness, weakness, sleepiness or feeling faint.
Again, you should call your child’s provider if they show these symptoms.
With kids of all ages, Dr. Sabella says that urination changes are a major red flag. A child’s urine should normally be clear or a light yellow color.
“If a child’s urine appears golden, darker in color or seems concentrated, this suggests dehydration and is an indication to give the child more fluids. Additionally, a decrease in urination or wet diapers is a serious sign of dehydration in children. You should call your child’s doctor if an infant has less than six wet diapers per day or if a toddler or older child has no urine output within eight hours.”
Make sure your child takes breaks from play when it’s hot outside
It’s hard to pull kids away from the fun, but it’s necessary on the hottest days. “During any exercise or activity, it’s important to ensure good hydration in children. When it’s warm outside, hydration is absolutely necessary and kids of all ages should take breaks every 20 minutes. These breaks should give children the chance to hydrate, rest, get some shade and be in an air-conditioned or cooler environment,” says Dr. Sabella.
And avoid giving your child sugar or caffeine
Two things that aren’t good for dehydration — sugar and caffeine. If your child is dehydrated, Dr. Sabella says sugary foods and drinks aren’t wholesome options. Stay away from energy drinks and caffeinated drinks as well. She says the caffeine may act as a diuretic and cause a child to urinate more.