Chris Kresser a very succesful functional practioner, blogger and podcaster, from ChrisKresser.com is posting a series of articles called Tips for a Healthy Summer.
Sun protection is tricky business. On one hand, you don’t want to block the rays that synthesize vitamin D, but on the other, getting a sunburn is not a great idea either. Ideally, you should be spending enough time in the sun to build some level of base tan, but not so much that your skin has a chance to burn. Smart sun exposure is the most natural way to prevent sunburn or skin damage, and moderation is the key to getting the benefits of sun exposure without overdoing it. Twenty minutes to an hour of sun per day should be plenty to make enough vitamin D, depending on how dark your skin is.
But what if you’ll be out in direct sun for several hours? Does this mean you should wear sunscreen? Sun protection is important if you plan to be out in the sun for a long enough time to get burned, but most sunscreens on the market are not beneficial or even safe. Stephan Guyenet explains on his blog how typical sunscreen fails to prevent melanoma, the deadliest form of skin cancer. Most commercial sunscreens have a slew of chemical ingredients such as fragrances, parabens, alcohols, chemical solvents and petroleum oils that break down when exposed to sunlight. (1)
Unfortunately, even natural sunscreen materials like zinc oxide could be problematic. (2) Researchers have recently discovered that, in vitro, zinc oxide may generate free radicals when exposed to UV radiation, which could damage cells and raise the risk of cancer. (3) More testing needs to be done, but this preliminary research shows that even natural sunscreen ingredients could have unforeseen consequences to your skin health. Until we know more, however, using a natural, mineral based sunscreen is still a better choice than the chemical sunscreens that are commonly available.
Mark Sisson has written a great guide on how to prevent sunburns using dietary strategies. He lists a variety of antioxidants and healthy fats that have been demonstrated to be anti-inflammatory and protective against cellular damage caused by UVA radiation. Additionally, there is some anecdotal evidence that coconut oil may have been used as a sunscreen by native Pacific Islanders. (4) While there are no studies testing the effectiveness of coconut oil as sun protection, it may be worth trying if you’re looking for a safe way to prevent sunburn. Ultimately, your best option is to stay in the shade or wear protective clothing once you’ve had adequate sun exposure, and skip the sunscreen altogether. Quoted From ChrisKresser.com