Do You Need Sunscreen in Winter? A Dermatologist's Year-Round Answer

Cold air tricks people. The sun feels weak, so sunscreen goes in the drawer with the swimsuits. A bright, sunny winter day can fool you because your skin cannot feel UV. It does not provide any heat. The warmth you feel from the sun is infrared, which we call heat, but the damage to our skin comes from UV. Here is what actually happens to UV in winter, and how I tell patients to handle it.

Does the Sun Really Get Weaker in Winter?

Partly. In winter the sun sits lower in the sky, so its rays travel through more atmosphere before they reach you. Less direct rays mean a somewhat weaker effect on us, but that effect is never zeroed out. When the sun is lower on the horizon, the atmosphere filters out a large share of UVB, the shorter wavelength that causes most sunburns. On a typical winter day in much of the US, the midday UV Index runs lower than in summer.

UVA is a different story. Its longer wavelength passes through the atmosphere more easily, so it drops far less than UVB through the seasons. UVA penetrates deeper into the skin, causes wrinkles and brown spots, and contributes to skin cancer. It also passes through clouds and standard window glass, which I covered in the sunscreen myths I hear every week.

You may have read that winter sun is actually stronger because the Earth is closer to the sun and the ozone layer is thinner. The first part is technically true. The Earth is closest to the sun in early January. But the difference in distance is small, and the low angle of the winter sun matters far more. The ozone claim does not hold up either. Over most of the US, ozone does not thin out in winter, and it tends to run higher in late winter and spring. Winter sun is not stronger. It is just easier to underestimate.

Why Do People Burn on the Slopes in Winter?

Snow and altitude stack the deck. Fresh snow can reflect up to 80% of UV, so you get hit from above and below at the same time. Altitude adds more, since there is less atmosphere above you to filter UV, which I explained in my post on how I use the UV Index to plan the day.

Reflected UV can reach areas of your face that sunscreen usually misses: under the chin, under the nose and inside the nostrils, the ears, the lips, and the skin around your goggles. Cold and wind make it worse, because you never feel warm enough to think about a burn until it is too late.

I ski and snowmobile in the Idaho and Wyoming mountains. Every winter I see, either on the slopes or in my dermatology clinic or both, the classic raccoon face of the person who wore ski goggles and no balaclava or face mask. Their entire face is red from sunburn except for the white around the eyes from goggles or sunglasses. This is unfortunate, and I'm not being judgey about the way they look. Winter should be the easiest time of year to cover up. Even a thin layer of clothing can be enough to protect your skin. A balaclava and goggles should protect you from the shoulders up. Then even on a warm spring ski day, a lighter layer can be protective against the UV. It's an even more epic experience on a bluebird day to carve up the slopes and not get sunburned. For those who want to let their long hair fly in the wind with just a pair of goggles or sunscreen, I hope they will use sunscreen, like SolRX. One application in the morning can make a huge difference.

Winter should be the easiest time of year to cover up. Always have something between the sun and your skin.Lindsay D. Sewell, MD, MBA

What SPF Should You Use in Winter?

The same one you use in summer. I recommend a broad-spectrum SPF 50 or higher year-round, and SPF 50 is not too much for everyday use. The reason is simple: most people apply far less sunscreen than the amount used to test the SPF on the label, so the protection they actually get is lower than the number on the bottle. Starting higher gives you room for real-world application coming in lower than intended.

What can change in winter is the texture. Cold, dry air pulls moisture from the skin, so many people do better with a cream or lotion sunscreen than a lightweight gel. If your skin is sensitive, windburned, or irritated, a mineral sunscreen with zinc oxide or titanium dioxide is usually the gentlest choice, since it sits on top of the skin.

How Do You Protect Your Skin on a Ski Day?

• Apply before you gear up. Put sunscreen on before boots, gloves, and helmet, when you can reach your face, ears, and neck easily.
• Reapply at least every 2 hours. Wind, snow, sweat, and wiping your face with gloves all wear sunscreen off. A lodge break is a good reminder.
• Cover up! It's cold. There is no excuse not to put a layer of clothing between you and the sun to keep warm and sun protected. Areas under the chin, nostrils, ears, back of the neck, and around goggles are often missed if you are using sunscreen instead of clothing to cover up.
• Protect your lips. Use a lip balm with SPF 30 or higher and reapply often. Lips have very little natural protection.
• Protect your eyes. Wear goggles or sunglasses with UV protection. Snow reflection can burn the surface of the eye and the eyelids. Skin cancer on the eyelids is unfortunately not rare, and it is always a big deal to the patient.

For a long day outside, a long-wear formula helps. SolRX Waterblock SPF 50 lotion is built with 8-hour water resistance to hold up through sweat and snow. For quick touch-ups, a stick like the SolRX Clear Zinc Face Stick SPF 50 fits in a jacket pocket. Reapply at least every 2 hours, as the label directs.

How Does Sunscreen Fit a Dry Winter Skin Routine?

Keep it simple. A gentle cleanser, a good moisturizer, and sunscreen in the morning covers most people well. Moisturizer goes on first, then sunscreen as the last skin care step, before any makeup.

Can you skip moisturizer and just use sunscreen? If your skin is not dry, a moisturizing sunscreen can be enough. But winter skin is usually dry, and dry, cracked skin is irritated skin, so most people do better with both in the colder months. If your skin is windburned, chapped, or stinging, go gentle: a fragrance-free moisturizer and a mineral sunscreen are the least likely to sting.

Do You Need Sunscreen Every Day in Winter If You Work Indoors?

If you spend most of the day inside, daily sunscreen on your face, neck, and hands is still a good habit, mainly because of UVA. It passes through car and office windows, and it adds up over months and years. According to the World Health Organization, indoor workers still receive roughly 10 to 20% of the yearly UV exposure that outdoor workers get.

The good news is that it does not have to be complicated. A daily moisturizer with SPF, or your regular sunscreen on the areas the sun can reach, covers most of it.

The Bottom Line: Always Put Something Between You and the Sun

It's hard to ignore that big, bright, glowing fireball in the daytime sky. Those who do pay the price. In the winter, it is sometimes seen solely as a source of light and heat. Even in the winter, however, we cannot forget it is also a source of UV radiation that is trying to kill us. We must cover up. Covering our skin with clothing, hats, balaclavas, scarves, gloves, and other winter attire in the coldest time of year makes the most sense of all the seasons, since we are not cooling ourselves by removing clothing. We are trying to retain heat, so we pile it on. Well, doing so also can keep UV away. Always have something between the sun and your skin, whether clothing, shade structures, or sunscreen. For the gaps of exposed skin, sunscreen is essential and should not be forgotten or dismissed. It can play a vital role in keeping our skin sun protected year round.