Do you ever feel thirsty and dehydrated but besides drinking what appears to be a significant amount of water? This is a pretty common thing and can take place for a number of reasons: you may not be drinking sufficient water to meet your body’s needs, you may have an electrolyte imbalance, or something else is going on internally.

We talked to a lot of physicians and nutrition experts about water intake to help you understand why you may be feeling the same way. Everything you need to know is right here:

How much water should I drink on a daily basis?

Before you can confront dehydration, you must first understand the basics of drinking more water. Even though everyone’s needs are slightly different, our experts say the easiest rule of thumb for deciding how much water to drink each day is to split your weight in half and drink that quantity in ounces. In other words, if you weigh 140 pounds, you should drink approximately 70 ounces of water per day. That’s about nine glasses, or a few Hydro Flask refills.

However, that regime isn’t set in stone; you may require more or less water based on your diet, meds, home environments, toxic risks, activity levels, and other aspects. Foods high in water can also be hydrating, so if you eat a lot of cucumbers, strawberries, watermelon, celery, and other hydrating fruits and vegetables, you may not need to drink as much to stay hydrated

The significance of maintaining hydration

It’s no secret that hydration is critical—we hear about it all the time. However, there is less information available about the why behind it all. “Good hydration is critical for our bodies to function,” says Linda Anegawa, a physician at the virtual health platform PlushCare. “Water in our bodies ensures that blood circulates properly, wastes are efficiently removed, body temperature is regulated through sweating, and hormones and signaling molecules required by the nervous system are produced.”

Is it possible to overdo it on water?

Whereas drinking water is essential for maintaining our health, it is possible to overhydrate. “Drinking too much water can actually result in a condition known as water intoxication, in which excess water dilutes important blood electrolytes such as sodium, potassium, magnesium, and calcium,” Anegawa explains.

According to Anegawa, this can result in complications such as muscle cramping, weakness, heart arrhythmias, and fatal brain swelling, but the more severe complications are rare and would necessitate drinking more than a gallon or two of water per day.

What if I drink plenty of water but still feel dehydrated?

There are several reasons why you may feel dehydrated despite drinking the suggested amount of water. Here’s what our experts had to say:

• You could be suffering from an electrolyte imbalance: One of the most common reasons you may feel dehydrated even after drinking a lot of water is electrolyte imbalance: “Sometimes, if we drink a lot of water but don’t eat enough fruits and vegetables, our electrolytes—sodium, potassium, magnesium, chloride, and so on—can get flushed out with the water.” Our bodies produce a thirst response, causing us to drink more water and dilute electrolytes even more.
• You’re sweating a lot: Sweating causes your body to lose electrolytes and fluids. If you don’t replenish both of these, you may start feeling pretty awful: If we sweat out a lot of fluid and then drink a lot of plain or bulk water that lacks the electrolytes we just sweated out, it can actually flush out even more electrolytes and be dangerous. Sports drinks may be a better option than guzzling water during an intense workout, especially on a hot day, to help you stay hydrated and maintain proper electrolyte balance. 3 However, be mindful of how much you consume—many sports drinks are high in sugar.
  
• You’re hungry: Irritability, for example, is a symptom of both hunger and dehydration. Self explains that this is more common in people who have blood sugar dysregulation.
  
• It takes time for your body to hydrate: Even if you drink a lot of water, it can take a while for your body to be properly hydrated if you become dehydrated. Anegawa explains how this works: “Fluids first enter our vascular system after we drink water.” Fluid is then divided out into other body tissues, briefly lowering the fluid content in our circulation. Even if you drink a lot of water, more may be required to ensure proper rehydration.”
• You’re taking a medication that’s a diuretic: Some medications are diuretics, which means they remove salt and water from the body. If you take a diuretic medication, you may become dehydrated as essential fluids and electrolytes are tried to push out of your body.