I don’t know about you, but when I go out in the sun, I’ll only wear a pair of hugely oversized $500 Dolce & Gabbana shades so that I’m easily recognized by the paparazzi. But apparently, says the Wall Street Journal, I need not have spent my entire month’s paycheck on my designer specs.

Investigating whether or not sunglasses like my D&Gs are really worth the leopard-print plastic they’re made out of, WSJ’s Brett Arends found six things you should keep in mind before shelling out piles of cash for brand name shades.

1. Most sunglasses are made by the same company
Whatever the name on the side of the sunglasses, there’s a good chance they’re made by Italian manufacturer Luxottica. Among the brands they manufacture for are Prada, Burberry, Chanel, Polo Ralph Lauren, Paul Smith, Stella McCartney, Tiffany, Versace, Vogue, Persol, Miu Miu, Tory Burch, Donna Karan and my beloved Dolce & Gabbana.

2. In many cases, the same company is also selling you the glasses
In addition to being the shades-makers for the world, Luxottica also owns LensCrafters, Pearle Vision and Sunglass Hut. Writes Arends: “Make of it what you will. But if your financial advisor was actually employed by the mutual fund company that he recommended for your portfolio, you’d at least want to know.”

3.The markups are as big as they seem
Luxottica says its gross profit on a pair of sunglasses is $.62 on the dollar. Even after deducting sales and advertising costs, overhead and brand licensing royalties it’s still making 52 cents.

4. Those expensive sunglasses may not be any better for your eyes, either
Arends quotes a the chair of ophthalmology at Tufts University as saying that “For about $40 you can get a pair that offers 100% protection against ultra-violet rays. If you spend maybe $70 you should be able to get a pair with decent quality polarizing lenses that cut out glare. Beyond that, the medical benefits tail off pretty fast.”

5. An inexpensive pair of sunglasses from the pharmacy isn’t the worst thing in the world
According to Dr. Reza Dana, director of the cornea and refractive surgery service at Massachusetts Eye and Ear Infirmary, “The main reason people wear sunglasses is to block out (regular) white light… and from that point of view, cheaper glasses work pretty well.”

6. Those fancy glasses are really costing you a lot more than you realize
Between damage, loss and keeping up-to-date with the latest styles, “these things add up. Indeed they compound. Even at, say, 4% interest, $200 a year over 50 years adds up to $30,000.”

What’s the most that you pay for sunglasses?

FYI, the folks over at Glasseyes are always blogging about ways to save on eyewear.

Are Designer Sunglasses Worth the Price? [WSJ]

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