There is a serious reason why you should be extra careful if you have a window seat on an airplane, and I really would never have guessed that

Earlier this year, Tiktok Findingfiona users uploaded a travel video that received serious attention, winning more than 2 million views and 1000 comments. In the publication, she emphasized the importance of wearing sunscreen for flights, citing reports of people who cause more damage to the sun when they are at a greater altitude.

“Although you are inside the plane, because of the high altitude, you are actually experiencing a stronger UV radiation, especially if you are in the window seat,” she says in the video.

According to dermatologists it Partially correct – but it is also a little wrong. “The good news is that the real risk of a flight or someone who flies from time to time is probably low,” says Dr. Elizabeth Jones, Assistant Professor of Dermatology at Thomas Jefferson University Hospital in Philadelphia.

But Jones noted that for the flight crew members and pilots, the risk is higher. “People who fly professionally, they will be exhibited much more to ultraviolet light – especially if they are in the cockpit – the size of the windshield” and given the whole time they spend at a larger altitude, she said.

Jones cited a 2015 study, which found that pilots and cabinet crew have approximately twice a large incidence of melanoma, a rarer, but more serious form of skin cancer, than the general population.

So, there is a connection between flying and damage to the sun. Below, dermatologists explain what you need to know about the risk of sun damage when you are at an altitude.

Windows airplane blocks most UVB rays, but not all UVA rays.

“The aircraft windows effectively block most UVB rays,” Jones said, citing rays that can cause sunburn and skin cancer. So even if you sit in the window seat, you probably won’t be sunburn after flight. But this does not mean that other damage cannot occur.

This also applies to non-air windows, said Dr. Jennifer Holman, a dermatologist with American dermatology partners Tyler in Texas. “Most typical windows in a house or car will filter … such as 97%, 98% of UVB radiation, which is usually the wavelength that people think about it causes sunburn,” she said.

While Windows blocks these rays they don’t block All rays. According to Jones, the windows of the plane do not completely keep UVA rays that can “cause premature aging, wrinkles and can eventually contribute to skin cancer.” (Jones noted, however, that “some of the older windows block about 50% of the UVA rays” and “some of the more new models are more effective in blocking UVA.”)

Again, this goes beyond the planes: Holman said that most glass windows, including your car windows and windows in your local cafe, also do not offer UVA protection. In general, “most glass does not filter UVA,” she noted.

Wearing sunscreen on an airplane can protect you from those harmful rays, which Holman said to penetrate “deeper into the skin” and put you “at risk of different types of skin cancer, including the most death form of skin cancer, melanoma.”

So who needs sunscreen on a plane?

The short answer: all.

Sunscreen is important for people to wear daily, whether you are taking a flight or not. “As a dermatologist, of course, I encourage all my patients to wear my sunscreen as a daily habit every day, only for the exposures we encounter, and the free radicals that are out in the world of UV radiation,” Holman said.

While it is important for everyone to wear sunscreen on an airplane, Jones said that some people should be careful.

“Who should consider wearing sunscreen on a plane?” she said. “Certainly someone with a personal or family history of skin cancer may want to get this additional protection using sunscreen.”

People with honest skin who are more sensitive to the sun should also consider this additional protection. The same applies to people with medical conditions that make them susceptible to sun damage, and people who are on drugs that increase the sensitivity of the sun, Jones noted.

Holman said that when you shop for sunscreen, you need to find one that is labeled “wide spectrum”, which means that it protects both UVA and UVB rays. This is always necessary, including in an airplane, when you are not protected from this UVA light.

Beyond the Holman sunscreen stressed that others are also useful. “The importance of physical protection also – wearing hats, protective clothing, sunglasses – all these things continue to be important as we are protecting against ultraviolet exposure,” she said.

This article originally appeared in Huffpost.