Yoga is more popular than ever.

But it has the potential to infect you.

"We see fungus of the feet daily. It's a very common thing, especially in the warmer months," says Dr. Jerald Sklar.

Dermatologist Jerald Sklar explains fungus thrives in moist damp environments, so sweaty exercise mats can provide a perfect breeding ground for athlete's foot.

"You’ll have some whiteness, scaling and cracking of the toes. That's the first sign," says Dr. Sklar.

If unchecked, athlete’s foot can lead to toenail fungus, which is characterized by blackening of the nails.

"We clean our mats once a week using an antibacterial kind spray," says Robin Turner, who owns a yoga studio.

Robin Turner owns this yoga studio. While she has yoga mats available, she recommends bringing your own.

"Mats are very inexpensive, and we really are promoting people to own their own mats," says Turner.

At least one student is following her instructor's lead.

“I do it so much it was a normal investment for me.”