Feeling tired during the day may have nothing to do with needing rest — you might just need a glass of water.
Mild dehydration also can produce disruptions in mood and cognitive functioning, according to the journal Nutrition Reviews.
So how much should you be drinking?
“There’s actually a lot of confusion on it,” said Dr. Ravi Johar, chief medical officer for United Healthcare in the Missouri-Illinois area. “Some of the confusion comes around when you hear about how much you should be drinking a day, versus how much fluid you should get in a day.”
Typically, 80% of a person’s water intake is from drinking beverages, and 20% comes from food.
“Women generally need a little bit less fluid than men, women should get about 11-and-a-half cups of fluid a day, or 92 ounces, whereas men need about 15-and-a-half cups, or 124 ounces a day,” Johar said, referencing overall intake.
People who eat a lot of fruits and vegetables may only need six 8-ounce glasses of water a day versus the ubiquitously-mentioned eight to 10 glasses.
“And if you’re eating a lot less, you may actually need to drink more than that eight to 10. The goal is to try to get to that 92 or 124 ounces a day of fluid,” he said.
People who drink too much water can end up in a coma or die from what’s called water intoxication — but Johar said that’s rare.
Signs of dehydration include:
- Being thirsty
- Having really dry, cool skin
- Dry mouth
- Headache
- Muscle cramps
- Dark yellow urine
- Not urinating
- Fatigue
“I think the most important thing to add is that water is incredibly important to keep our bodies running, and that the body lets you know when it needs more water,” Johar said.
“So really listen to it. Drink whenever you’re thirsty. Don’t feel like you have to do any set amount of fluid. Your body will let you know what you need, and it’s best to listen to it.”