By Erik Derr (staff@latinospost.com) | First Posted: May 26, 2013 11:06 AM EDT

If sunscreen is on your Memorial Day weekend shopping list, please know the best sunscreens on the market are not the most expensive.

In fact, according to a new product study by Consumer Reports, some of the priciest bottles of sunscreen on the shelves provide the least effective protection.

The nonprofit consumer advocacy group tested 12 popular sunscreens for its July 2013 issue of Consumer Reports magazine and found some products don't meet the SPF claims made on the bottles and that paying more for sunscreen doesn't necessarily mean consumers are getting better product.

The acronym SPF stands for sun protection factor and the numbers don't refer to how long onr can spend under the sun without getting a sunburn, but to the amount of protection from UVB, or, shortwave ultraviolet light, the product offers. Sunscreens with SPF 15 filter out 93 percent of UVB rays, and SPF 30 filters out 97 percent, while SPF 50 blocks 98 percent and SPF 100 blocks 99 percent of UVB rays.

"Some of the priciest sunscreens Consumer Reports tested offered less than their labeled SPF value," the magazine said in a press release.

In June 2011, the FDA issued new sunscreen labeling guidelines aimed at ending confusion about the products' effectiveness that were to be implemented by summer 2012.

Under the regulations, sunscreens that protect against both ultraviolet A and B radiation must be called "broad spectrum" and sunscreens that don't protect against both must say so with a warning label on the bottle.

All the sunscreens evaluated by the Consumer Reports were magazine are broad spectrum.

Testers wore the sunscreens on an area of their backs, then UVB rays from a sun simulator were shined on five spots within the areas where the sunscreens were applied.

And, which sunscreen came out tops?

Target's Up & UP Sport SPF 50, with an overall score of 80, earned a "very good overall" rating by the magazine, as did five other sunscreens: Wal-Mart Equate Ultra Protection SPF 50, Coppertone Water Babies, Walgreens Continuous Spray Sport SPF 50, Hawaiian Tropic Sheer Touch SPF 30 and Coppertone Sport High Performance SPF 30.

Wal-Mart's Equate, priced at $0.63 an ounce, was named a "Consumer Reports Best Buy."

Both Badger Unscented SPF 34 lotion, at $5.52 per ounce, and All Terrain AquaSport SPF 30 lotion, at $4.33 per ounce, rated poorly at guarding against UVB rays. (Badger has actually been discontinued but can still be purchased online or at select stores.)

Also not recommended were California Baby SPF 30+, No-Ad with Avobenzone, Aloe and Vitamin E SPF 45, Neutrogena Wet Skin SPF 45+ and Kiss My Face with Hydresia SPF 40.

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