Have you ever been hard at work and 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

In order to combat this exhaustion, it’s important to ensure you’re drinking enough water before physical symptoms hit.

First, make sure to check in with yourself throughout the day. 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. (And try to practice a regular hydration Microstep, so you don’t get to this point to begin with.)

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, you know the drill: Refill your bottle!

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, especially if sweat losses occur during the day,” Millard-Stafford  says. Your activity levels can also play a role in how much water you need to drink to stay hydrated, so if you’re hitting the gym in the morning but don’t necessarily feel moody, you’ll still need to drink more than your stationary colleague. 

And if you feel great throughout the day? Make sure you keep up with your Microstep of drinking water so it stays that way.

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