According to a recent Consumer Reports , many sunscreens advertising a high SPF are not providing the promised level of protection.
NewsChannel 5 spoke to a dermatologist who said sun safety means reading reviews and reapplying frequently.
"It's a common question that we're getting in the office. 'What sunscreen should I be using. What brand, what SPF,'" said Dr. Jennifer Lee, a Clinical Associate Professor of Dermatology at Vanderbilt Medical Center.
She said there's no sunscreen on the market that blocks 100 percent of the sun's rays.
So, instead, choose one that is "broad spectrum" meaning it helps block out both UVA and UVB rays.
"Which we now know are both instrumental in causing skin cancer," she said.
Dr. Lee said a good sunscreen should be at least SPF 30 and you should be reapplying every two hours.
More expensive doesn't always mean better. At just $5, Consumer Reports gave Walmart's Equate Sport Lotion an excellent rating, while MD Solar Science's Mineral Moisture costs almost $40 and got a failing score, an 18 out of 100.
Dr. Lee uses a machine called the "reveal imager" to help her patients at REN Dermatology see sun damage in a more tangible way.
Lele Thompson works at REN Dermatology and has also tried the imager.
"I had a sun spot from driving in the car. I am in my 40s so it was getting darker and darker," she said.
Thompson said seeing the actual damage has helped her be more vigilant about shielding her skin from the sun.
"I know that you hear it all the time. Your dermatologist tells you and you see it on TV but believe it," she said.
Dr. Lee also recommends sunscreen that is "water resistant" and encourages large hats, big sunglasses and light clothing.