As the seasons change, maybe it’s time to put aside heavy duty sunscreen in favor of a natural alternative: extra virgin coconut oil.

“Coconut oil is a proven sunscreen that is still used by millions of people in the tropics as their sole source of protection from sunburn and skin cancer,” writes Bruce Fife, author of Coconut Cures: Preventing and Treating Common Health Problems with Coconut Oil and other books.

Citing a study conducted by Indian researchers, Fife explains how various oils, including olive, coconut, peanut, castor, sunflower, sesame, cod liver, and neem seed oils, were measured for their ability to absorb or block UV radiation. The researchers found that coconut oil performed relatively poorly in comparison to the other oils; it blocked only about 20 percent of the UV light. Yet, Fife claims, this is a good thing.

“Coconut oil protects the body from sunburn and skin cancer without blocking the beneficial UV radiation,” Fife writes in his newsletter. “Coconut oil … works by preventing free-radical reactions which lead to all the consequences caused by overexposure to the sun.”

His theory is that coconut oil permits just the right amount of UV rays so that skin can remain healthy. “Vitamin D is produced by the action of UV rays from sunlight interacting with cholesterol in our skin,” he writes in his newsletter. By not blocking out all the UV rays, then, coconut oil still allows for the necessary production of vitamin D.

That said, he advises “seasoning” any pale skin before spending too much time in the sun. This is a special process necessary for coconut oil to be beneficial. If you rub a thin layer of coconut oil over uncovered skin and remain in the sun for only 15 to 30 minutes at a time, you will only get pink the first day. Repeat this process in the next few days, staying out a little longer each time. “After about two weeks or so, your skin will be seasoned enough to stay outdoors for hours with a single coating of coconut oil,” writes Fife in his newsletter.

It's important to remember what you're using the oil for: to protect yourself from harmful ultraviolet radiation coming from the sun, which can cause skin cancer. Sun protection factor (SPF) is a number that refers to a product (or a natural oil's) effectiveness in blocking UV rays. The Centers for Disease Control And Prevention recommend using a sunscreen with at least SPF 15; as coconut oil is unrated, you cannot assume it will provide enough protection against skin cancer so you should consult a doctor before use.

Among Pacific Islanders, coconut oil has been used as a sunscreen for many years. In fact, anywhere palm trees grow, the indigenous people have included coconut oil as part of their traditional medicine. In addition to skincare, coconut oil is used to treat a variety of health problems including coughs, asthma, ulcers, fever, toothache, bronchitis, constipation, flu, wounds, and irregular or painful menstruation.

Source: Sobhana T, Kumar GM, Sampath S. Ultraviolet transmission through a few edible oils in the context of changing solar insolation. J Ind Geophys unlon 2004