On the Internet there are more and more recipes for cosmetics that can be made at home. Home-made sunscreens are also popular, including in Runet (Google sent out 492,000 results when asked for “do-it-yourself sunscreen”).
A new study published in the journal Health Communication showed that homemade sunscreens are generally ineffective and should be avoided. Researchers have analyzed how users of Pinterest, a popular image-sharing site, describe and evaluate homemade sunscreen recipes. Scientists studied in detail every fifth post devoted to such creams.
It turned out that in 95.2% of the 189 posts analyzed, the authors stated that their home-made products completely protect against ultraviolet radiation. Other users have saved some of these posts more than 21,000 times. While 68.3% of the posts promoted sunscreens, which, according to the researchers, are completely ineffective.
Researchers explain that home-made sunscreens have not been tested in laboratories and therefore may not protect against ultraviolet rays at all. "Homemade sunscreens are dangerous because they are not regulated and tested for effectiveness, like commercial ones. When you make the cream yourself, you don’t know if it is safe," the study says.
Some Pinterest cream recipes contain ingredients that really protect against UV radiation and are used in commercial creams, such as zinc oxide and titanium oxide. However, homemade creams may not contain enough of these substances, or these substances may not be evenly distributed throughout the mixture, resulting in uneven protection.
In addition, unlike commercial creams, homemade ones may not be waterproof.
"Some of these ingredients naturally provide some protection from the sun, but not to the extent that these pins [Pinterest posts] claimed. This combination of ingredients will definitely not give you SPF 50. Using homemade sunscreens can lead to severe sunburn, and potentially to skin cancer in the future, "said lead author Lara Mackenzie.
It is also important that home-made sunscreens will almost certainly not protect against both UVA and UVB rays.
The false sense of security they inspire can be harmful.
"The Centers for Disease Control and Prevention notes that having a history of sunburn, especially at an early age, can increase your risk of developing skin cancer. Therefore, it’s important to apply sunscreen that has been tested and proven effective, starting with childhood, "summed up the results of the Mackenzie study.
The American Academy of Dermatology recommends the use of a sunscreen that provides protection for a wide spectrum of action, that is, protection against UVA and UVB rays. The cream should also be waterproof and have an SPF of 30 or higher.
When in the sun, cream should be applied every two hours, and if you are swimming or sweating heavily, then more often.