While dehydration is often associated with being thirsty, that’s not the only warning sign our bodies share with us.
The condition can occur when you use or lose more fluid than you take in, which can impact the body's ability to perform its normal functions, say experts.
The body loses fluids and water through sweating and urination, according to Cleveland Clinic.
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"In warm and hot weather in particular, your body loses water and fluid faster," Mike Sevilla, M.D., a family physician with Salem Family Care in Salem, Ohio, told Fox News Digital.
"If these fluids are not replaced, the body becomes dehydrated."
Although anyone can become dehydrated, it can be especially dangerous for vulnerable groups, such as young children and the elderly.
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5 surprising symptoms of dehydration
Doctors shared with Fox News Digital some of the signs of dehydration that go beyond thirst.
1. Sweating
It may come as a surprise that excessive sweating could be an indicator of dehydration.
Water is lost when you sweat, so if you’re engaging in vigorous activity and don't replace fluids, you can become dehydrated, according to Mayo Clinic's website.
"In heat and humidity, we lose more water in the form of perspiration, which is what triggers the body to tell the brain that it needs water and the actual feeling of thirst," Lauren Fine, M.D., a board-certified dermatologist with Fine Dermatology in Chicago, told Fox News Digital.
2. Sickness
Illness is an often overlooked cause of dehydration. With excessive vomiting or diarrhea, the body can quickly become depleted of fluids — especially with younger people and older adults, Sevilla said.
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"Having a fever or an infection can also lead to dehydration, because fever can cause you to sweat and thereby lose fluid," he cautioned.
3. Fatigue
One of the initial signs of dehydration is fatigue.
"People usually ignore this symptom, thinking that they are just tired," Sevilla said — but it can progress to dizziness and lightheadedness.
To combat fatigue, he recommends consuming beverages with electrolytes to boost energy levels.
4. Dark urine
If your urine is amber- or honey-colored, or dark orange, this may indicate that your body isn't getting enough water, according to Health.com.
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"If you're dehydrated and are holding onto more of the actual water itself, the urine will become darker and darker," Michael A Palese, M.D., chair of the Department of Urology at Mount Sinai in New York, told Health.com.
5. Skin changes
Dehydrated skin can look dull and dry, and can also show premature signs of aging, such as surface wrinkles.
"Skin cells need water to survive," said Fine.
To keep the skin hydrated, she recommends drinking water while working out, reducing intake of coffee and other caffeinated beverages, and eating more fruits, vegetables and legumes.
When to seek medical attention
The longer dehydration continues without intake of sufficient fluids, the worse the symptoms become, according to Sevilla.
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Severe dehydration leads to dizziness, confusion, increased heart rate and low blood pressure, the physician said.
"The more severe the case of dehydration is, the more difficult it is for people to drink enough fluid to help the situation," he said.
In cases of severe hydration, the person may need to visit the hospital or emergency department to receive fluids via IV.
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Both doctors emphasized the importance of being proactive and drinking water or electrolyte-containing fluids before exercising or playing sports.