With any luck, Memorial Day weekend will bring in weather good enough to be slathering on the sunscreen at least every two hours when outdoors.

And to know which are the best products to put on your skin during the unofficial start of summer, the May issue of Consumer Reports rated 18 top-selling sunscreens. The products ranged from SPF 30 to SPF 75+ and were lotions, sprays, or a spray foam. They varied in price from a low of $.59  an ounce to a high of $20.59 per ounce.

To judge the performance of each product, sunscreens were tested on people, and the ultraviolet B (UVB) radiation protection was rated before and after swimming in fresh water for up to 80 minutes. Testers also checked whether the product stained clothing.

In addition, they did a new "critical wavelength" test required by the FDA to see if the sunscreen truly offered broad-spectrum UVA and UVB protection. UVB radiation is the main cause of sunburn, while UVA rays penetrate deeper, where they can cause long-term damage and age skin.

Top 7 Sunscreens

Most products offered good UVB protection, while many helped block UVA rays.

The cheapest sunscreen outscored the most expensive product in the test, leading researchers to conclude that "price had nothing to do with performance."

After testing, Consumer Reports named three of its highest-rated sunscreens as "Best Buys," while four other top-scoring products were "Recommended."

Best Buys 

• No-Ad lotion with aloe &vitamin E, SPF 45, $.59/ounce
• Walgreens continuous spray sport, SPF 50, $1.30/ounce
• Coppertone oil-free foaming spray, SPF 75+, $1.67/ounce

Recommended 

• All Terrain Aqua Sport lotion, SPF 30, $4/ounce
• Banana Boat clear ultra-mist sports performance active dry protect spray, SPF 30, $1.63/ounce
• Coppertone sport high performance ultra sweat-proof spray, SPF 30, $1.67/ounce
• Eco all natural sunscreen body lotion, SPF 30, $4.72/ounce

Two sunscreens flunked the "broad spectrum" test:

• Alba Botanical natural very emollient sunblock sport, SPF 45
• Banana Boat Kids tear-free, sting-free, SPF 50+

No matter which product you put on, Consumer Reports offered these tips to help stay safe in the sun:

• Choose a waterproof sunscreen with at least an SPF of 30. Above 30 provided little extra protection.
• Use 2 to 3 tablespoons of sunscreen; reapply every two hours and after swimming or sweating.
• Wear a hat and protective clothing in addition to using sunscreen.
• The FDA is looking into possible risks of inhaling spray sunscreens. Consumer Reports recommends avoiding using sprays on kids. If used, spray on hands first before applying to the face.
• The group also recommends that pregnant women may want to avoid products with retinyl palmitate.

Read labels and ingredients carefully. New FDA requirements for sunscreens and other cosmetic products containing an SPF value will soon make it easier for consumers to understand the labels and what claims, such as "broad spectrum" or "water-resistance," really mean.

SOURCES:Consumer Reports, May 2012 issue.News release, Consumer Reports.

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