You may think you’re drinking enough water, but if you spent most of the day with a cup of coffee by your side, you’re probably more dehydrated than you think. After all, the numbers don’t lie: the human body is about 70% water, and we lose up to two and a half liters of it per day doing just normal activities. Even breathing causes a lot of fluid loss—we exhale around half a liter over the course of the day.
How much water should you drink a day?
In order for the fluid balance in our bodies to be maintained, drinking enough water is clearly key. According to the Mayo Clinic—which uses insights from the U.S. National Academies of Science, Engineering and Medicine—adult women should take in about 11.5 cups or 2.7 liters of fluids per day; men should get 15.5 cups or 3.7 liters per day. And even though about 20% of those totals can come from food (fruit, soup, vegetables, etc.) very few of us really do achieve such high quantities.
But how do you know if you really are dehydrated? We asked Dr. Lela Ahlemann, a specialist in dermatology, proctology, and nutritional medicine to share her insights. Here, she tells us the seven most common signs you’re not drinking enough water.
7 Signs You’re Not Drinking Enough Water
Dry mouth and a feeling of thirst
A very typical sign of dehydration is—obviously—experiencing the feeling of thirst. This, along with a dry mouth, is often the first sign that you need water. And, for good reason: Not only does a dry mouth signify a lack of fluids, but also that your immune system is becoming weakened. “A dry mouth can lead to the oral mucosa, an immune defense, being weakened and you can become more prone to infections,” explains Ahlemann. “If you can’t manage to drink water when you have a dry mouth, then you should at least rinse it out with a little liquid.”
Dark urine or less urine production
“When we drink too little, our urine becomes concentrated and changes color,” explains Ahlemann. According to the doctor, pale yellow urine is ideal. “If your urine is dark, that’s a clear sign that you should definitely drink more. Looking at your own urine is the easiest self-test to check whether you’ve drunk enough water.”
Headaches and dizziness
“Headache and dizziness can be caused by reduced blood volume due to dehydration, which means that our brain is no longer well supplied with blood and nutrients,” says Ahlemann, who adds that if you often feel dizzy, you should definitely visit a doctor.
Fatigue and problems concentrating
Fatigue and difficulty concentrating can also be due to a lack of fluids and are one of the most common signs you’re not drinking enough water. “Here, too, the reduced blood volume is to blame, which, as mentioned, means that our brain is not optimally supplied,” explains the doctor.
Dry skin and lips
According to Ahlemann, typical signs of dehydration include dry skin and lips. You can find out whether this is the case for you with a small self-test: “Pinch the skin on the back of your hand between two fingers and pull it up. If it seems slow to return to its original state, that is a sign of dehydration.” In addition, many people experience increased itching due to dry skin.
“The skin may also appear paler because the oxygen and micronutrient supply is no longer optimal,” she adds.
Dark circles under the eyes
According to Ahlemann, “if you don’t drink enough, the blood becomes thicker, which tends to make the vessels more visible. Sunken eyes, dark circles, and increased eye wrinkles can be a sign that you’re not drinking enough.”
Constipation
A typical sign that you are not drinking enough? Constipation. It’s easy to understand why this happens: If you drink too little, your intestines withdraw too much water from the stool, which in turn reduces their volume. When the intestinal tract is not full, the body doesn’t feel compelled to eliminate waste. “In medicine, we speak of constipation when we talk about solid stools due to water deprivation,” explains Ahleman. “But what many people don’t know is that drinking too little can also cause a bloated stomach.”