Experts Explain The Health Issues That Come From Not Drinking Enough Water

The thirst is real.

by Suzannah Weiss and JR Thorpe
Originally Published: 
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Dehydration can creep up on the best of us. Hot days are for lounging in the park with a frosé, and water can drift to the bottom of your priority list. “As the weather heats up, it’s more important to make sure to keep yourself hydrated," Dr. Natasha Trentacosta M.D., sports medicine specialist at Cedars-Sinai Kerlan-Jobe Institute, tells Bustle. "When you lose more water through sweating, breathing, or urinating than you take in through drinking foods or ingesting water-heavy foods, your body is at a net loss for water and may not have enough fluid to carry out its normal functions." And dehydration can lead to some health issues that might seem counterintuitive, from dry eye to cramping legs.

This doesn't mean you necessarily need eight glasses of water a day; experts instead recommend listening to your body. You can tell if you're dehydrated by looking out for signs like dizziness, dry mouth, or not having to pee. If you notice them, drink up — whether it's a bottle of cold water, or an electrolyte-rich sports drink designed to refresh you after a hard workout.

Here are some health issues you may not know can be caused by dehydration.


Dry Eye

“When you are dehydrated, your eyes produce less tears so they are no longer properly lubricated, which can lead to dry eye,” Dr. Ryan Parker, O.D., optometrist and director of professional services at lens company Essilor, tells Bustle. Dry eye occurs when you don’t produce enough tears to see properly or wash things out of your eye, which can lead to eye irritation and blurred vision.


Eye Strain

Eye strain, with symptoms that include tired eyes, blurred vision, headaches, and double vision, can also occur when your eyes are insufficiently lubricated. “Drinking plenty of water will help flush out salt in the body and properly hydrate your eyes to help reduce eye strain,” Parker says.



Dehydration leaves your muscles more prone to cramps, Dr. Trentacosta tells Bustle. Heat cramps, where the body's muscles involuntarily seize up, commonly happen in athletes who exercise in hot climates and sweat a lot, draining their bodies of sodium and electrolytes. This is why it’s important to stay hydrated during a workout or even when you’re getting a massage.



If you're not feeling particularly steady on your feet or have an attack of vertigo, dehydration may be to blame. When you don't drink enough, Dr. Trentacosta says, your blood pressure plummets, which may mean you start feeling dizzy when you get up quickly.


Dry Skin

When you’re dehydrated, your whole body dries out, including your skin, your lips, and your hair, says Caleb Backe, a wellness expert at Maple Holistics. “There's a reason that chapped lips, dull hair and broken skin result in the cold, dry winter — it's because your body needs hydration in order to nourish those bodily areas.” Water is the biggest component in skill cells, and a study in Clinical, Cosmetic & Investigative Dermatology in 2015 found that dietary water has a real influence on your skin's physiology and health.



If your mind feels slower than usual or just not totally there, ask yourself how much water you drank that day. "Electrolytes, including sodium and potassium, help carry the electrical signals from cell to cell within the nervous system," Dr. Trentacosta says. When you're dehydrated, your low levels of electrolytes can impede your thinking, according to a 2018 study published in International journal of environmental research and public health.


Kidney Stones

"If you are not ingesting enough fluids, you are not producing enough urine and flushing out your urinary system," Dr. Trentacosta says. "Dehydration can lead to a buildup of the waste products in the body that are supposed to be filtered by the kidney." That can damage the kidney, and lead to kidney stones and UTIs. "There is less water to flush the sticking together of stone-forming crystals or germs," she says.

Moral of the story? Dehydration can be hard on pretty much every part of your body and brain. Drink whenever you're thirsty, and if you have any of these issues, ask yourself if a lack of water might be the culprit.


Caleb Backe

Dr. Ryan Parker O.D.

Dr. Natasha Trentacosta M.D.

Studies cited:

Palma, L., Marques, L. T., Bujan, J., & Rodrigues, L. M. (2015). Dietary water affects human skin hydration and biomechanics. Clinical, cosmetic and investigational dermatology, 8, 413–421.

Zhang, J., Zhang, N., Du, S., He, H., Xu, Y., Cai, H., Guo, X., & Ma, G. (2018). The Effects of Hydration Status on Cognitive Performances among Young Adults in Hebei, China: A Randomized Controlled Trial (RCT). International journal of environmental research and public health, 15(7), 1477.

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