When it comes to fueling our bodies for optimal health, most of us are laser-focused on the foods we eat. Often, though, we hardly acknowledge the even more significant role that water plays in our body’s every function and thus survival and overall well-being. While a human being can generally survive for a month or two without food, they won’t make it for more than a week or so without H2O. (After all, about 60 percent of the human body is made of water!)
Among its many functions, water helps us maintain a normal body temperature, cushions and lubricates our joints, protects our spinal cord, helps us eliminate waste, and more. Still, many people fail to drink enough water—and may be suffering the consequences without even realizing it.
Unlike hunger, which sets in to signal that it’s time to eat, we don’t usually get significant thirst cues until we’re already mildly dehydrated, notes functional dietitian Jenna Volpe, R.D.N., L.D., C.L.T. This is less than ideal, especially for people who are super-busy and might be more reactive than proactive about hydrating, as well as for those who don’t particularly enjoy drinking plain old water.
While thirst is one indicator that you’re a little dehydrated, it’s hardly the only one. Here’s a look at the different ways your body will let you know to chug a glass of water, pronto.
1. Dry mouth
When your body lacks adequate hydration, you might experience dry mouth (also known as xerostomia). This dryness in your mouth occurs when your saliva glands aren’t able to produce enough saliva, explains Volpe. “When dehydrated, saliva production is compromised, leading to dry mouth, which can happen even in cases of acute, mild dehydration,” she says.
2. Headache
If you’ve ever had a hangover, you know all too well the misery that is a “hangover headache,” which is exacerbated by the loss of hydration that accompanies a night of drinking. This same type of headache can occur after a day of being out in the sun, in which you sweat but do not hydrate adequately.
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“If you have a headache, the first thing you should ask yourself is what you drank today and if you are hydrated or not,” says naturopath Kiera Lane, N.M.D., MSAc, L.Ac., Dipl. Ac., director of Arizona Natural Medicine. “It could be due to pressure in blood vessels resulting from dehydration.”
3. Dizziness
Any time you feel dizzy or lightheaded, dehydration is a likely culprit. “This symptom of dehydration occurs when you don’t have enough water in the body because water helps regulate blood volume, ultimately altering blood pressure, electrolyte balance, and more,” Volpe says. “When you’re moderately dehydrated, subsequent changes in blood volume, blood pressure, and electrolyte balance can cause dizziness.”
4. Brain Fog
Many people don’t realize that dehydration can actually leave you feeling foggy or even confused. The reason for this? Dehydration can lead to reduced blood flow to the brain, which can then negatively impact your cognitive function, notes Lane. “This can manifest as mild forgetfulness or mild changes in mood to more extreme symptoms, such as agitation, incoherent or slurred speech, or not being oriented to place or time,” she says.
If you start noticing that you’re feeling foggy, unfocused, or out-of-sorts midday, take inventory of your hydration and pour yourself a cup of water to see if that perks you up.
5. Fatigue
When properly hydrated, your body is like a well-oiled machine—but the opposite can be true when it’s dehydrated. If you’re in need of H2O, you may notice unusual fatigue. “While most people associate fatigue with not enough food or sleep, dehydration is also a possibility,” says Volpe. “Since dehydration leads to reduced blood volume, the fatigue is caused by the drop in blood pressure and reduced blood flow to the brain.”
6. Dark-colored urine
Perhaps the easiest, at-home method of gauging your hydration status: Look at the color of your urine. “When you’re well hydrated, the color of your urine is a very clear, pale yellow because the water helps dilute the toxins being eliminated,” says Volpe. “On the flip side, you will usually see darker colored urine when you haven’t been drinking enough water because the kidneys try to conserve water, ultimately making more concentrated urine.”
7. Leg cramps
In order for your muscles to function at their full capacity, they need to be hydrated, which allows for the proper exchange of lactic acid and other metabolites involved in contracting, relaxing, and fatigue, explains Lane. “Dehydration makes muscles more susceptible to muscle cramps since both water and electrolytes are needed for muscles to function properly and contract,” she says. “These cramps tend to be felt in the legs, as we use these muscle groups extensively for getting up from chairs, walking, and moving throughout our day.”
How to stay well-hydrated throughout the day
If you’re experiencing one or more of these signs of dehydration, the best thing you can do is pour yourself a glass of water (like right now) and continue to drink another glass every two or three hours, notes Lane. This should help you get back into a more hydrated state—and ease any undesirable symptoms.
Generally, Lane recommends drinking a glass of water upon waking so that you start off your day adequately hydrated. (You might be slightly dehydrated after a full night of sleep without any water intake.) She also recommends using a BPA-free water bottle that has measurements on it in order to see just how much you are drinking. (Experts often recommend a baseline of half your body weight in ounces of water per day.)
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You can also increase your water intake with food. Lane recommends making a point to snack on juicy fruits like watermelon to increase water intake—especially if you struggle with drinking water or need extra H2O because of heat, exercise, or health status.
Another way to overcome any resistance to the bland taste of plain water? Consider rehydrating through the use of electrolyte supplements. Electrolytes are a group of minerals (sodium, potassium, calcium, magnesium) that help to even out the usual functions within your kidneys and keep your body systems working in homeostasis, says NYC-based naturopathic doctor Lana Butner, N.D. Try a drink mix like Bare Performance Nutrition Electrolytes or Kaged Hydra-Charge (both available in The Vitamin Shoppe’s in-store Hydration section) for a boost of flavor and these important minerals.