(CNN) - The hot and humid weather is keeping most people perspiring, but doctors said it's good to sweat because it keeps people healthy.
Catherine Lowry believes in exercise, yet even though she works hard enough to sweat she doesn't, which can lead to problems.
"It's the after affect, I never quiet cool down, a headache will set in and I feel like I have the flu," Lowry said.
Sweating maintains body's temperature by cooling it down. When you're hot and you sweat, moisture evaporates and cools off the body. Not sweating can cause overheating.
"There can be complications with heat stroke, heat exhaustion, mind doesn't tend to work very well, kidneys can suffer, various other things," said Dr. David Hansen with Foxhall Internists.
Not everyone sweats the same way.
Men sweat more than women because females sweat at a higher temperature, causing less perspiration.
And people who are overweight sweat more, because fat acts as an insulator that raises the temperature in the body.
Some people, like Lowry, sweat very little, which is called hypohidrosis, and those who sweat excessively, have a condition known as hyperhidrosis.
"People who sweat excessively, tend not to have significant medical issues, it's more of a cosmetic issue for many," Hansen said.
Because Lowry doesn't sweat, she needs to work out indoors during the summer months and exercise outdoors only in the cooler temperatures.
"I basically give up running in the summer, it ruins my day," she said.
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