(CNN) - Hot temperatures and more time spent outdoors being active are both reasons to pay attention to proper hydration in the summer.
You get some water through foods like fruits and vegetables, but 80 percent of your hydration comes from water and other liquids.
So brush up on your H2O IQ with this quick quiz.
True or false? Let your thirst be your guide.
“You want to outpace your thirst. You do not want to get thirsty. When you're thirsty, you're already mildly dehydrated,” said dietitian Jessica Avasthi. “I would suggest keeping a water bottle with you at all times. That way, you can access water wherever you are, and you can actually track how much you're drinking and being sure that you're keeping hydrated consistently.”
What about the commonly-held belief that 64 ounces of water a day is sufficient?
That's also false.
“That's your bare minimum,” Avasthi said.
Aim for about nine glasses at 8 ounces each for women and 12 for men, whether it's from the tap or bottled. Just because water comes out of a bottle does not mean it's safer.
Next, some drinks hydrate more than others. It's true.
“Water is a perfect hydration policy. Stick with water,” Avasthi said.
Some caffeinated beverages are OK. But be wary of alcohol because it dehydrates.
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