You may have heard the news: Protecting yourself from the sun is actually detrimental to your health—at least, according to a 2016 study in the Journal of Internal Medicine that’s part of a growing body of research re-examining the role sunlight plays in our well-being. But while there’s mounting evidence that not getting enough sun could be a serious risk, there’s a lot to unpack before you decide to leave your parasol behind on a trip to Dillon Reservoir. At the heart of the controversy is vitamin D, the nutrient we get from food, supplements, and ultraviolet radiation (aka sunshine).

Higher levels of vitamin D have long been correlated with everything from reduced inflammation to lower rates of skin cancer and heart disease. But researchers haven’t been able to verify causation between oral vitamin D supplements and many of those health benefits. This has led some experts to suspect it’s actually sunlight, not vitamin D, that’s responsible for healthier bodies. The Journal of Internal Medicine study seems to bolster that hypothesis: In a review of nearly 30,000 Swedish women, it found that those who spent more time in the sun lived up to two years longer than those with less sun exposure. Such research has launched plenty of click-bait headlines, including “Soak Up The Sun This Vacation, It Can Really Lower Heart Disease Risk.”

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Such conclusions, however, are reductive—and dangerous—interpretations of the science, says Dr. Neil Box, a cancer researcher at the University of Colorado Anschutz Medical Campus: “People who are getting out in the sun are people who are often exercising and getting a load of other health benefits from that.” Besides, Denver’s strong outdoors and fitness cultures mean it’s likely most locals enjoy enough sun during their daily activities, Box says. The World Health Organization recommends five to 15 minutes of sun on your hands, arms, and face two to three times a week during summer to stay healthy. And because of our high elevation, the city receives about 26 percent more UV radiation than areas at sea level.

That number likely plays into another alarming statistic: Colorado ranks seventh in the nation for skin cancer deaths per capita, according to the Centers for Disease Control and Prevention. So, it’s extremely important for Coloradans to avoid the sun when ultraviolet rays are strongest, around 10 a.m. to 4 p.m. You should also wear protective clothing such as broad-brimmed hats or long-sleeved shirts when you can and use shade and sunscreen when you can’t. “We’re not saying you have got to be a troglodyte, that you’ve got to be a cave dweller and stay inside and avoid the sun,” Box says. “We just need to be careful with how we balance these kinds of health messages.”