Is Natural Sunlight Good for Psoriasis?

When I was a child newly diagnosed with psoriasis, I was told by my dermatologist that sunbathing would help to clear up my plaques. I felt self-conscious taking my shirt off at the community pool or the beach, but my family and I found other ways for my skin to catch some rays.

My dad assembled an above-ground pool in the backyard where I could cool off, practice swimming, and expose my psoriasis to the summer sunlight. To everyone’s surprise, my psoriasis completely cleared up that summer, when I turned 10 years old.

Phototherapy (also known as light therapy) hasn’t cleared my skin of psoriasis as effectively as it did in those early years, but it has become an integral part of my treatment routine.

Since those days, I’ve learned more about how to use natural sunlight to treat psoriasis, including important safety measures. Here’s what I know about how to enjoy the summer rays safely.

Is It Safe to Treat Psoriasis With Sunlight?

I asked my dad, who also has psoriasis, if he planned on getting more natural sunlight for his skin. Although he lives five minutes away from a beautiful Southern California beach, he said no without hesitation. He didn’t feel he could accurately measure his light exposure outside the same way he can with his home phototherapy unit.

His response illustrates one of the challenges of using natural sunlight as a psoriasis treatment: It’s hard to measure your dose.

The National Psoriasis Foundation (NPF) also recommends caution, noting that “using sunlight to treat psoriasis is not recommended for everyone. Sunlight is not as effective for the treatment of psoriasis as prescription phototherapy. Talk with your healthcare provider to find out if treating with sunlight is right for you.”

Natural sunlight contains both ultraviolet A (UVA) and B (UVB) rays. Of the two, UVB works better for treating psoriasis.

When I started using a home phototherapy unit again a few years ago, I agreed with my dermatologist to limit my natural sunlight exposure. Like my dad, I chose to use artificial light therapy with narrowband UVB (NUVB) light in a controlled setting, instead of sunbathing.

Sunburn Can Be a Psoriasis Trigger 

With either natural or artificial light, sunburn is a concern. I learned the hard way that sunburn causes my psoriasis to flare. One time my skin felt uncomfortable after a phototherapy session at the hospital clinic; the next day it turned red and burned.

The resulting psoriasis flare took a while to calm down. Ever since then I’ve been extra cautious about avoiding sunburn.

A scratch or burn can cause psoriasis to flare in a reaction known as the Koebner phenomenon. About 1 in 4 people with psoriasis will experience new lesions where they don’t usually get them at the site of a skin injury, such as a sunburn.

At the same time, I can’t avoid the sun completely. We have about 265 sunny days per year here in the greater Sacramento area, according to the National Climatic Data Center, making it one of the sunniest cities in the United States.

When I head out in the summer, I take a number of steps to limit my sunburn risk.

Protective Clothing Can Help Prevent Sunburn and Flares

Protective clothing is one way to avoid sunburn. Sunglasses for me are a must, because the skin around my eyes tends to sunburn easily. My sun hat has a brim that protects my face from scorching rays and a drape that covers my neck. As a bonus, it adjusts comfortably and carries a 50+ UPF rating.

The Skin Cancer Foundation explains that “Ultraviolet protective factor (UPF) measures the amount of UV radiation (both UVA and UVB) a fabric allows to reach your skin. For example, a UPF 50 fabric blocks 98 percent of the sun’s rays,” which greatly reduces the amount of light that passes through to the skin.

The foundation also lists recommendations for sun-safe clothing. For example, darker colors absorb more UV rays, keeping them from reaching your skin. Loose-fitting clothes protect better than tight clothes because stretched fabric can allow sunlight through. Certain fabrics prevent UV penetration better than others.

Apart from my hat and sunglasses, I struggle to dress for sun protection. I typically wear 100 percent cotton clothes, which may have a UPF rating as low as 5, according to Cleveland Clinic. I have read about chemical treatments for clothes that can increase UPF values, but I’m unsure whether they will irritate my skin.

When the temperature outside exceeds the century-degree mark in July, I probably won’t wear long sleeves and pants. That’s when sunscreen becomes especially important.

Sunscreen Is Vital — Even on Plaques 

I used to wonder why I should wear sunscreen if sunlight could benefit my psoriasis and help produce vitamin D, a nutrient that people with psoriasis often lack. So, I would head out initially without sunscreen with plans to apply it after a few minutes of sun exposure. But I often forgot to do it once I’d started an activity, which potentially exposed my skin to too much harmful ultraviolet radiation.

Now before going out for a long walk, playing sports, or going to the beach, I apply sunscreen first — even on my psoriasis. I take a vitamin D supplement as directed by my healthcare providers to make up for the vitamin D my body won’t produce.

The NPF suggests using a sunscreen that has a “broad spectrum,” which protects against both UVA and UVB rays. It should be rated 30 SPF or higher, made for sensitive skin, and fragrance-free. They also recommend talking to your dermatologist about sunscreen for your psoriasis.

After some trial and error, I’ve found that Banana Boat Sport sunscreen does a great job of protecting my skin while not irritating my psoriasis.

Outdoor Activities During Peak UV Periods May Raise Sunburn Risk

As a weather enthusiast, I enjoy tracking and charting local conditions on my home weather station. Mine also reads the solar radiation and UV index in my backyard.

I’ve observed that the highest intensity ultraviolet light does not coincide with the heat of the day. I recently noted the strongest UV levels at 1 p.m., with the high temperature at 4 p.m. The Environmental Protection Agency confirms what I’ve discovered: “The sun’s rays are strongest between 10 a.m. and 4 p.m.”

If you don’t have a weather station like mine that measures the UV index, use a weather app on your phone to check your local UV reading. Avoiding or limiting sun exposure during those midday peak hours can reduce the chance of sunburn. If you do need to be outside, seek shade.

Summer Fun Can Be Sun-Safe

I’m looking forward to enjoying the long summer days just around the corner. My son and I are planning to hike in the mornings around Sacramento and the San Francisco Bay area. The neighborhood park across the street is calling me to walk or shoot a basketball.

Whatever plans or activities you have for this summer, make sure you are sun-safe and avoid sunburns that can cause psoriasis flares. And it never hurts to check in with your healthcare professionals about the best way to do that, given your personal situation.

You can read more about my experiences on my website, PsoHoward.