New research finds that while consumers rate sunscreens that absorb well and smell nice most highly, many of these products do not adhere to American Academy of Dermatology guidelines. Skin cancer is currently the most common cancer in the United States, and it is estimated that 1 in 5 Americans could develop skin cancer in their lifetime.

Exposure to ultraviolet (UV) light is the most preventable risk factor for all skin cancer types. The American Academy of Dermatology (AAD) recommend that to be protected from the sun’s harmful UV rays, a sunscreen that offers broad-spectrum protection against UVA and UVB rays – that is, SPF 30 or higher and water-resistant – should be used every day.

Consumer reviews on websites can sometimes give a good indication of the quality and reliability of a product. However, results from an article published online by JAMA Dermatology questions if sometimes consumer reviews can do more harm than good.

Shuai Xu, M.D., M.Sc., of Northwestern University Feinberg School of Medicine in Chicago, IL, and co-authors searched the keyword “sunscreens” on the U.S. retailer Amazon.com in December 2015.

The team selected the top 1 percentile of sunscreen products according to an average consumer review of four stars or greater. They also collected descriptive data including SPF strength, price, and active ingredients, in addition to the top five most helpful and critical comments for each product.

Of the 6,500 products that were categorized as “sunscreens,” the top 65 were chosen for analysis. The sunscreen products had a median price of $3.32 an ounce and a median SPF of 35, with 89 percent of sunscreens being SPF 30 or higher. Of the products, 92 percent claimed to be broad-spectrum, and 62 percent were labeled as water or sweat resistant. Creams were the most common sunscreen vehicle, followed by lotions and sprays.

Water exposure reduces the effectiveness of a sunscreen when a person sweats or is immersed in water. Water-resistant sunscreen is effective for up to 40 minutes in water, and very water-resistant sunscreen is effective for up to 80 minutes in water.

A total of 40 percent of the highest rated sunscreens on Amazon.com did not adhere to AAD guidelines, mostly due to lack of water and sweat resistance. Consumers identified positive and negative features of a sunscreen product most commonly by cosmetic elegance attributes, such as “absorbs well,” “nice smell,” “too thick,” “greasy,” rather than how effectively the sunscreen product performed.

According to the article: “Dermatologists should balance the importance of cosmetic elegance, cost, and AAD guidelines for sun protection in making their recommendations to consumers.” Limitations of this study include the fact that the source data represent 9 percent of all sunscreen sales and that generalizability may be limited because of the lack of reviewer demographic information.

Most of the products analyzed claimed additional product features in addition to sun protection. The authors note that consumers should be advised that labels such as “safe for sensitive skin,” “preservative free,” or “noncomedogenic” are marketing mechanisms and are not performance standards, such as SPF, that are regulated by the Food and Drug Administration (FDA).

“Dermatologists should counsel patients that sunscreen products come with numerous marketing claims and varying cosmetic applicability, all of which must be balanced with adequate photoprotection,” the study concludes.

Written by Hannah Nichols – Medicalnewstoday.com

The first lab-grown epidermis – the outermost skin layer – with a functional permeability barrier akin to real skin has been developed by scientists. The new epidermis, grown from human pluripotent stem cells, offers a cost-effective alternative lab model for testing drugs and cosmetics, and could also help to develop new therapies for rare and common skin disorders.

An international team led by King’s College London and the San Francisco Veteran Affairs Medical Center (SFVAMC) has developed the first lab-grown epidermis — the outermost skin layer — with a functional permeability barrier akin to real skin. The new epidermis, grown from human pluripotent stem cells, offers a cost-effective alternative lab model for testing drugs and cosmetics, and could also help to develop new therapies for rare and common skin disorders.

MIT researchers may have discovered a fountain of youth for skin — at least a very temporary one.

The researchers have developed a “second skin” that could be used to smooth wrinkles, protect skin from damage, or administer medications to treat skin conditions, such as eczema. But, right now, the product only does its job for about a day.

“It’s an invisible layer that can provide a barrier, provide cosmetic improvement, and potentially deliver a drug locally to the area that’s being treated,” Daniel Anderson said in a university news release. He is an associate professor in MIT’s department of chemical engineering.

“Those three things together could really make it ideal for use in humans,” Anderson added.

As people age, their skin becomes less elastic and firm, the study authors noted. These signs of aging may be worsened by sun damage. For the past decade, the research team worked on developing a protective coating for the skin that could restore a youthful appearance and protect the skin from further damage.

“We started thinking about how we might be able to control the properties of skin by coating it with polymers that would impart beneficial effects,” said Anderson. “We also wanted it to be invisible and comfortable.”

For their research, the scientists created a library of more than 100 potential polymers. The researchers explained that they tested each material in order to determine which one would most closely match the appearance and characteristics of healthy skin.

The product used in this study included silicone-based polymers that can be manipulated into an arrangement known as a cross-linked polymer layer (XPL).

The second skin is applied in two steps. Both layers are applied as creams or ointments. Once on the skin, XPL is nearly invisible. It can remain on the skin for up to 24 hours, the study authors said.

“It has to have the right optical properties, otherwise it won’t look good, and it has to have the right mechanical properties, otherwise it won’t have the right strength and it won’t perform correctly,” said the study’s senior author, Robert Langer, a professor at MIT.

The polymer may be applied directly to the skin as an undetectable thin coating, which mimics the properties of healthy, young skin, the researchers explained.

Laboratory tests showed the polymer was able to return to its original state after being stretched more than 250 percent. In contrast, real skin may be stretched about 180 percent, the authors said.

“Creating a material that behaves like skin is very difficult,” said one of the study’s authors, Barbara Gilchrest, a dermatologist at Massachusetts General Hospital in Boston. “Many people have tried to do this, and the materials that have been available up until this have not had the properties of being flexible, comfortable, nonirritating, and able to conform to the movement of the skin and return to its original shape.”

When tested on people, researchers found the polymer was able to reshape “eye bags” beneath the lower eyelids, and the effect lasted about 24 hours. It also treated dry skin and improved hydration, the study found.