Sunscreen may be worthless at best and dangerous at worst. I made that point in my last blog. Now, another recent scientific study corroborates this conclusion. The authors of this study probably expected a different outcome—an outcome opposite of what they found. The researchers wanted to discover which sun-protection behavior was most effective in preventing sunburn. Hence, they designed a cross-sectional investigation using a nationally representative sample of about 32,000 US adults. They interviewed each participant in person. This is especially relevant when attempting to achieve the most accurate results possible. We can conclude, therefore, that their findings regarding sunscreen use and other “sun-protective” behaviors probably have validity. Seeking shade, wearing a hat or visor, and wearing long sleeves and or pants were other sun-protective behaviors included
Sunscreen and sunburn results
In addition, they identified the subjects as sun-sensitive individuals or non-sun-sensitive individuals. Fifty-four percent of the subjects were women, and 15,992 of all individuals were considered sun-sensitive (fair skinned). Those who used only sunscreen had the highest sunburn likelihood (62.4%). The group with lowest likelihood of sunburn did not use sunscreen, but engaged in the other protective behaviors (24.3% sunburned). In addition, among 12,566 non–sun-sensitive individuals, those engaged in all 4 protective behaviors had the lowest sunburn (6.6%). The highest likelihood of sunburn was among those who only used sunscreen (26.2%). “the most surprising and counterintuitive finding was that regular sunscreen use, in the absence of other protective behaviors, was associated with the highest likelihood of sunburn.” according to Kasey Morris, who led the study, 
Other sunburn results:
Finally, you should understand this: sunscreen use associates closely with sunburning. That has been known since 2014. This is not a good product, therefore. We should protect ourselves from overexposure. But we should do it the way God (or Mother Nature, if you prefer) intended it: Cover up with clothing when you start to redden, seek shade, or go indoors for awhile. Good health depends on obtaining regular, non-burning sun exposure.
Avoid Sunscreen for another reason:
The state of Hawaii has now banned its use. This is because of the destruction of the coral reefs caused by certain ingredients in this chemical soup. In addition, the risk of melanoma skin cancer has increased exponentially since the first sunscreens were introduced. How much? By about 3,000%. And yes, you read that correctly. Do you have other questions? You should probably read the sunscreen section of my new book, Embrace the Sun, to learn more. https://www.amazon.com/Embrace-Sun-Marc-B-Sorenson/dp/069207600X
 Kasey L. Morris, PhD; Frank M. Perna, EdD, PhD. Decision Tree Model vs Traditional Measures to Identify Patterns of Sun-Protective Behaviors and Sun Sensitivity Associated With Sunburn. JAMA Dermatol. Published online June 27, 2018