(CNN)As we welcome sunshine and warmer weather after being hunkered down for weeks, many of us will be more excited than ever to spend time outside.
But whether you are simply looking for some fresh air during a walk or hoping to get an extra dose of the "sunshine vitamin" — that is, immunity-supporting vitamin D — dermatologists say it's as important as ever to practice safe sun to protect against skin cancer.
Skin cancer includes melanoma and non-melanoma skin cancers, which include basal cell carcinoma and squamous cell carcinoma.
"Melanoma is the most deadly, and the chance of it taking your life is directly proportional to the stage at which it is diagnosed," said board-certified dermatologist Dr. Bruce H. Thiers, president of the American Academy of Dermatology. "If you can treat it early when it is just in the skin, it's basically 100% curable."
Even better news is that most skin cancers are preventable, and there are steps you can take to minimize your risk.
"We're not telling anyone to be a hermit. We know people like to be outside, but be sensible," Thiers said.
"If you go to the beach, stay in the shade under an umbrella. Avoid sun between 10 a.m. and 2 p.m. Wear sun protective clothing and UV protected sunglasses and apply sunscreen on all exposed skin."
Vitamin D and sun exposure
That's right — even during pandemic times, it's important to apply sunscreen properly, despite the fact that doing so will block vitamin D synthesis in skin.
Vitamin D has received a lot of attention for its role in supporting immune health. The vitamin is part of the immune response to an immediate threat and activates our first line of defense against infection, explained Dr. Adam Friedman, professor and interim chair of dermatology at The George Washington University School of Medicine and Health Sciences.
Our skin can synthesize vitamin D if it's exposed, without sunscreen, to ultraviolet B light from the sun. "It was an evolutionary mechanism [to meet D needs] when we didn't have a Walgreens down the street from us," Friedman said. "Now, we can get vitamin D from our diet or through supplementation."
Food sources of vitamin D include fatty fish, eggs, tofu, mushrooms, cheese and fortified milk and juices.
Dermatologist Dr. Carolyn Jacob, founder and director of Chicago Cosmetic Surgery and Dermatology, recommended that people get tested for vitamin D levels, which can alert you as to whether or not you should consider a vitamin D supplement.
"Since UV [ultraviolet] light is a carcinogen, now there's no reason to put one at risk for skin cancer, skin aging and even immune suppression," Friedman said.
That's right: Too much UV radiation from sunlight, even with sunscreen applied, can actually suppress the immune system, making you more susceptible to infection, Friedman explained, though he added this would be more likely if you get burned.
"You need very little time [to synthesize vitamin D in skin] but it's hard to standardize that, depending what time of day it is, where you are in the world and UV index changes," Friedman said. "We can't say, 'after three minutes and 30 seconds, you'll get exactly enough D and be safe.'"
Friedman also warned it takes less than 10 minutes of direct exposure from 10 a.m. to 2 p.m. to get enough UV radiation to cause DNA damage that can ultimately lead to skin cancer.
Practicing safe sun
The sun is a source of UVA and UVB rays. UVB rays are responsible for producing sunburn, while UVA rays play a greater role in the development of premature skin aging, including wrinkles and age spots.
Both UVA and UVB rays can cause skin cancer, however. Because of this, it's best to apply a sunscreen that has broad spectrum protection, which blocks both UVA and UVB rays, Thiers explained. Sunscreen should also be water-resistant and have a minimum SPF of 30, according to the American Academy of Dermatology. You should generously apply it to all skin not covered by clothing, and reapply every two hours or after swimming or sweating.
If you use a spray sunscreen, Friedman recommended spraying the sunscreen into your hands and then applying, which will prevent losses into the air.
Sensible photoprotection also includes wearing wide-brimmed hats, sunglasses and sun protective clothing that is labeled "UPF" and is tightly weaved, "so the amount of UV radiation that would penetrate is quite low," said Dr. Henry W. Lim, chair emeritus of the department of dermatology at the Henry Ford Health System and former president of the American Academy of Dermatology.
Seeking shade is also important, "but clouds are not what we consider shade," Jacob said. "Shade is a physical barrier between the sun and you, like a UPF umbrella ... or even sitting under a fully leaved tree."
"UVA rays penetrate clouds, but UVB don't, so you won't get burned, and you don't have a cue that it's risky," Jacob said. UVA rays penetrate deeper than UVB and can even penetrate window glass. They cause both wrinkling and skin cancer, she said.
Wearing a mask to protect against Covid-19 infection also serves as physical protection. "Most are pretty efficient at blocking UV radiation," Friedman said.
"If you are using a mask, I'm a big fan of mineral sunscreens and stick sunscreens ... the stick adheres to skin a little bit better and doesn't get as runny as liquid." Most of the stick sunscreens that use zinc oxide are SPF 40 or higher, Jacob explained.
Apply the stick to the ears, forehead and neck, including the back of the neck, especially if hair is short or tied up.
Since sweat can get trapped inside the mask and can cause a red, scaly, itchy rash, Friedman recommended a facial moisturizer with sunscreen for those with a history of eczema, acne or rosacea.
You might also consider wearing a sun protective hat with a face mask built into it — something Jacob recently purchased for her regular runs. "It's very comfortable and lightweight!" Jacob said.
The importance of telemedicine
If you are concerned about a spot on your skin and are quarantining, teledermatology can help to identify atypical lesions or concerning growths in the safety of your home. "It's a triage tool that allows us to maintain social distancing," Friedman said.
"Patients love it. ... It's quick and convenient and also covered by the majority of insurance companies, or inexpensive cash pay. One of our concerns with everyone putting off coming in is the chance of missing something," Jacob said.
"The important things are to take a look at your skin in the mirror; look for spots that are bleeding or not healing; or a bump on your skin in a sun-exposed area that is bleeding, crusting or flaking ... that's something you want to make an appointment for."
Zoom capabilities help Friedman see how the skin moves as a person is moving around and how the skin responds when a patient presses on a lesion or rash — something that is lost in an image.
But even with a high definition photo and camera, patients will often still need to come into the office for a biopsy.
"The greatest limitation is being able to say with confidence that this is a dangerous lesion," Friedman said. "Today I did 23 teledermatology visits. I'm bringing one patient in on Wednesday, and it's going to be something bad."
Because skin cancer is highly treatable when caught early, dermatologists advised performing regular skin self-exams while looking out for the ABCDEs, a system recommended by The American Academy of Dermatology to spot the warning signs of melanoma:
• A is for asymmetry: One half of the spot is unlike the other half.
• B is for border: The spot has an irregular, scalloped or poorly defined border.
• C is for color: The spot has varying colors from one area to the next, such as shades of tan, brown or black, or areas of white, red or blue.
• D is for diameter: While melanomas are usually greater than 6 millimeters — or about the size of a pencil eraser — when diagnosed, they can be smaller.