Is plain water enough? As temperatures rise, a local dietitian weighs in on what fluids will fill you up.

Sweating is our body’s way of shedding heat, registered dietitian Vicky Retelny said.

“We lose 17 to 24 ounces of water just from perspiration, which is normal,” she said. “But in the heat, we lose more than that.”

On a typical day, drinking two to three liters of water does the trick – that’s about nine, 8-ounce glasses for women and 13 for men. Kids ages 4 to 13 require about six to seven cups a day.

“So, when it’s this hot, typically, we can lose more than we take in,” Retelny said.  

Retelny says 80 percent of our water intake should come from fluids, primarily water, the other 20 percent can come from food.

“High-water foods are fruits, vegetables, you can get water in fruit smoothies and soups,” Retelny said.  

Keep water close by so it’s easy to sip throughout the day. If you’re working out, consider a sports drink or beverages with added electrolytes – charged minerals that control fluid balance, regulate blood pressure — and help keep our heart beating and maintain the correct pH balance in your blood.

“As an athlete that’s working out outdoors, you can lose up to a liter of water. So you really want to be replenishing water and electrolytes,” Retelny said.  

When should you reach for products like Pedialyte or Liquid IV?

“You should use an electrolyte-enhanced beverage that’s a little more concentrated if you know that you’ve lost fluid through sweat or vomiting or diarrhea,” she said. “So you want to pay attention to that.”

Fifty percent of our body weight is water. It helps regulate digestion and move glucose in our bloodstream. When we’re running low, signs of dehydration include feeling dizzy or light-headed; trouble focusing; headache; irritability; an increase in heart rate; and urine that is dark in color.

“Pay attention to the color of your urine. It should be a pale lemonade color,” Retelny said.  

 Older adults, pregnant women and people who take blood pressure medications are more prone to dehydration, which can be a medical emergency when the condition is severe.