Consumer Reports looked into the effectiveness of different sunscreens.

The researchers took a survey of 1,000 people and found most people value the SPF level when deciding which sunscreen to buy, a Consumer Reports news release reported.

The Consumer Reports National Research Center team tested 20 sunscreens in order to determine which where good and which were not-so-good.

They found that many of the products fell between four and 40 percent below their claims. An SPF 30 sunscreen that is 40 percent below its claim would only be providing an SPF of about 18.

The researchers also found variability in protection against UV rays.

According to Food and Drug Administration (FDA) claims sunscreen must have a critical wavelength of 370 nanometers in order to be labeled as broad spectrum.

Two of the products were found to be below that regulation.

"Our findings underscore the importance of choosing from our recommended sunscreens. If none are available, a product rated Good will provide adequate protection. Using any sunscreen is better than using none, but it's just one part of a smart sun-protection strategy," the news release stated.

Consumer Reports has released their critical-wavelength and SPF results to the FDA for further evaluation.

"Consumers just need to be careful when they buy sunscreen, that they are looking at the labels and questioning the information they are reading," Trisha Calvo, Consumer Reports deputy editor said, WebMD reported.

The sunscreens recommended by Consumer Reports include: Banana Boat's Ultra Defense Max Skin Protect SPF 110 spray; Coppertone Water Babies SPF 50; BullFrog Water Armor Sport InstaCool SPF 50+ spray; Neutrogena Ultimate Sport SPF 70+ lotion; Walgreens' Well Sport SPF 50 spray; Walmart's Equate Ultra Protection SPF 50; and Target's Up & Up Spray Sport SPF 50 spray, WebMD reported.

To see complete list of sunscreens that did not earn recommended ratings click here.

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