Effectiveness not most important to Amazon sunscreen reviewers

Shockingly, advice from trained dermatologists is more useful when buying sunscreen than Amazon reviews, or so a study by a lot of doctors says!

Some doctors examined the most highly rated sunscreens on Amazon and determined that many of them don't work nearly as well as advertised. Disappointing, but probably not shocking.

Via the LA Times:

To get some insight into what makes sunscreen appealing, researchers from Northwestern University examined customer reviews on Amazon.com, where about 9% of all sunscreen is purchased. Among the 6,500 sunscreens available on the site, researchers focused on the 1% with the highest customer ratings.

Of these 65 sunscreens, seven (or 11%) did not have an SPF of at least 30, five (or 8%) did not protect against both UVA and UVB rays, and 25 (or 38%) were not designed to withstand water or sweat.

The most common reason that products in the study failed to meet the academys criteria was that they could be rinsed away by water or sweat.Digging deeper into the top 1%, the researchers focused on the 10 with the most customer reviews a proxy for popularity and found that half of them werent water-resistant. That meant they flunked the dermatologists test.

After analyzing the top-rated comment for each of the 65 sunscreens, researchers found consumers cared more about factors like whether the product felt greasy or was difficult to rub in than they did about its effectiveness. However, effectiveness still outranked concerns about skin compatibility (i.e. whether a sunscreen caused acne) or about specific ingredients (such as nanoparticles or preservatives).

The products that made the top 1% ranged in price from 68 cents to $23.47 per ounce. In general, the sunscreens that met all of the American Academy of Dermatologys guidelines were more expensive than those that fell short, researchers found.

Still, I trust their reviews on self-published books.