Many skin moisturizers that claim to be fragrance-free or hypoallergenic are not, and may aggravate skin disorders such as psoriasis and eczema, a new study says.

Northwestern University researchers examined the top 100 best-selling, whole-body moisturizers sold at Amazon, Target and Walmart for affordability and content. They found that 83 percent of so-called hypoallergenic products had a potentially allergenic chemical.

The researchers also discovered that 45 percent of products marketed as fragrance-free contained a botanical ingredient or one that reacts to a fragrance that can cause a skin rash or skin allergy.

In addition, moisturizers with “dermatologist-recommended” labels cost an average of 20 cents more per ounce than those that did not have the label.

“We looked into what it means to be dermatologist-recommended, and it doesn’t mean much because it could be three dermatologists recommending it or 1,000,” said study senior author Dr. Steve Xu. He’s a resident physician in dermatology in Northwestern’s Feinberg School of Medicine in Chicago.

Moisturizers help patients with skin disorders by retaining moisture in the skin, reducing inflammation and helping to prevent infection, but buyers need to know if they contain allergens, Xu said. This is a challenge since manufacturers do not have to list every fragrance chemical in their products, he added.

The U.S. Food and Drug Administration has limited authority over cosmetics, Xu noted. “There’s a huge loophole relating to fragrances, which is the No. 1 cause of skin allergies related to cosmetics,” he said.

Xu believes dermatologists have a responsibility to know what’s in the skin products they recommend.

“The more we know about the science behind moisturizers, the better we can guide our patients to what they like, what is safe and what is affordable,” Xu said in a university news release.

For the study, the researchers used information from the North American Contact Dermatitis Group (NACDG), which identifies common skin allergens such as fragrance mix, parabens or tocopherol.

Only 12 percent of the best-selling moisturizers were free of such allergens, according to the report.

Looking for allergen-free skin products? Your best bets are white petroleum jelly, some coconut oils that are cold-pressed and not refined, Vanicream’s hypoallergenic products and Aveeno Eczema Therapy moisturizing cream, Xu said.

And the three most affordable moisturizers without any NACDG allergens: Ivory raw unrefined shea butter, Vaseline original petroleum jelly and Smellgood African shea butter, the researchers said.

The study was published Sept. 6 in the journal JAMA Dermatology.

More information

The U.S. National Institutes of Health has more on keeping your skin healthy.

Source: HealthDay