Have you ever been going about your day and were suddenly hit by a throbbing headache? What about dry mouth, or starting to feel shaky? If so, you’re not alone: You were probably dehydrated. And according to science, when the physical symptoms of dehydration hit, you’re already dehydrated. 

Staying hydrated is crucial to your general health and well-being. Getting enough H2O is what helps maintain the proper function of your heart, brain, muscles, and other internal organs, like the kidneys, which help regulate the body’s water balance and blood pressure. Keeping those internal systems running in tip-top shape is critical to safeguarding your health as COVID-19 continues to spread. What’s more, staying hydrated can help keep your lungs moist and prevent buildup that can later lead to infection. 

It’s also important to ensure you’re drinking enough water before physical symptoms of dehydration hit. A great way to do that is to start your day with a glass of water, and continue monitoring how you feel throughout the day. 

Check in with yourself periodically. If you’re experiencing a general feeling of exhaustion, or having a hard time completing tasks that require complex processing or your full attention, you may be well on your way to dehydration-land. When these feelings start, make sure to reach for your water bottle, not only when you first wake up, but also throughout the entirety of your day.

Another symptom to look out for is if you have not passed urine for some time. When you do go to the bathroom, if the amount is small and it’s dark-colored, you have not been drinking enough, Ron Maughan, Ph.D., a professor of medical and biological sciences at the University of St. Andrews, explains. If you’re adequately hydrated, your urine should be a yellow, pale straw color, Melnida Millard-Stafford, Ph.D., a professor of biological sciences and exercise physiology at Georgia Tech, adds. If it’s not: Refill your bottle! You can also keep one on your bedside table to remind yourself to take a drink as soon as you start your day.

It’s also important to remember that your personal signs of dehydration very likely look different than someone else’s. “Every individual is different with their water needs,” Millard-Stafford says. Your activity levels can also play a role in how much water you need to drink to stay hydrated, so you might need to up your water intake a little more on the days you’re going for a run or trying out an at-home workout. 

And if you feel great throughout the day? Make sure you keep up with your Microstep of drinking a glass of water first thing in the A.M. so it stays that way.