Do you really need sunscreen every day?

Sunshine seems like a strong argument against daily sunscreen.

When we go outside on a clear day, the sun’s ultraviolet light causes our bodies to release endorphins that reduce stress and improve mood. UV rays also tell our skin to produce vitamin D. And when we look up at the morning sun, our bodies recognize the day and adjust our sleep-wake cycle accordingly.

That might be reason enough for some people to skip the sunscreen. Dermatologists say their patients often worry about missing out on these benefits.

“This is one of the biggest obstacles in people’s minds: the idea that they shouldn’t wear sunscreen because they’re afraid they’re not getting vitamin D,” said Dr. Steven Q. Wang, director of dermatologic oncology and dermatology at Hoag Memorial Hospital Presbyterian in Newport Beach, California.

Recent studies reflect this fear: An A survey of more than 1,000 adults in the United States found that 11 percent of respondents felt that wearing sunscreen was more harmful than direct sun exposure. In another, 15 percent thought that exposure to sunlight was the only way to get vitamin D.

But sunscreen is also our best weapon against skin cancer, which can be deadly. The sun’s UV rays damage the DNA in your skin cells, and that damage can add up over time. Every time DNA repairs itself, there’s a chance it will develop a mutation that becomes cancerous.

We asked nine experts whether you should actually wear sunscreen every day, and whether the potential benefits of sunlight ever outweigh the risks. They all said there’s no safe amount of unprotected sun exposure and that you should wear a broad-spectrum sunscreen with an SPF of 30 or higher every day. Here’s what they want you to know about sunlight, sunscreen, and your health.

Does sunscreen block the mood-enhancing properties of the sun?

Not necessarily, said Dr. Elisabeth Richard, an associate professor of dermatology at the Johns Hopkins University School of Medicine. Even with daily sunscreen, you can still enjoy a mood boost from the sun’s visible light, or the light we can see with our own eyes. Visible light doesn’t cause DNA damage the way UV rays do, but it can increase serotonin, a brain chemical that helps regulate mood. That’s why using a light box can help ease symptoms of seasonal affective disorder, said Dr. Deborah Sarnoff, a professor of dermatology at New York University.

Dr. Richard said that if you’re worried about missing out on endorphins from sun exposure, you can compensate by staying active. And getting outside, whether it’s a solo hike, a day of gardening, or a picnic with friends, can boost your mood, even under a generous layer of sunscreen.

“People are happier when they’re out in the sun,” Dr. Wang said. “They’re more likely to lead active lifestyles and enjoy social gatherings.”

Does sunscreen disrupt my sleep cycle?

Your body’s internal clock depends on sunlight. When the sun goes down, your body produces the hormone melatonin, which promotes sleep. When the sun rises, it does the opposite to wake you up.

But just seeing sunlight can do this, says Dr. Richard.

“We get this benefit through our eyes, not through our skin,” she said. Even if you wear sunglasses — which protect your eyes from UV radiation — you see enough light to get the circadian rhythm-promoting benefits of sunlight, she said.

Can I get enough vitamin D from daily sunscreen?

Our bodies need vitamin D to absorb calcium and prevent conditions like osteoporosis, says Dr. Robert Ashley, an internist at UCLA Health.

When we’re exposed to UV rays, our skin cells produce vitamin D. But you can also get vitamin D through your diet, Dr. Ashley said. Foods that contain vitamin D include fatty fish like salmon, tuna and mackerel, and fortified foods like milk and cereal also contain it.

And even with daily sunscreen use, Dr. Sarnoff said, most people get enough UV exposure to make all the vitamin D they need. That’s because most people don’t apply enough sunscreen to fully protect their skin as often as needed.

“Even if you’re the best sunscreen user you can imagine and you put on a thick layer and reapply it every two hours, some of it will still get through,” said Dr. Sarnoff, who is also president of the Skin Cancer Foundation.

“The risk of skin cancer is much more real than the risk of vitamin D deficiency,” said Dr. Wang.

He and other experts believe that exposing your skin to UV damage simply isn’t worth the risk.

“People want to hear that they can get direct sun exposure for a period of time, maybe five minutes to a half hour, and that’s enough to get the benefits,” Dr. Sarnoff said. “But the truth is, why would you do that at all?”