Winter Sunscreen: Essential Protection for Healthy Skin

Updated: May 2026  ·  Reading time: approx. 6 minutes  ·  Written by Sarah, Founder of NAYA Skincare

It is true that the risk of sunburn is lower in winter. UVB intensity drops significantly at northern latitudes between October and March. But UVA radiation - which penetrates to the dermis, drives photoageing, breaks down collagen and elastin, and is present year-round regardless of cloud cover or temperature - continues to accumulate on cloudy days and sunny ones equally. For anyone managing pigmentation, redness or long-term skin health, the case for daily SPF does not change with the season.

UVA and UVB in winter - what actually changes

The two parts of the UV spectrum behave differently across seasons, and understanding the difference matters for how you think about winter sun protection.

The practical implication: in winter, the risk you are protecting against shifts from acute UVB damage (burning) to cumulative UVA damage (ageing, pigmentation, barrier stress). The argument for daily SPF is actually stronger in winter, not weaker - because UVA accumulates silently without giving any visible feedback that exposure is occurring.

The UV index and altitude

The UV index measures the intensity of UV radiation reaching the earth's surface at a given location and time. It is primarily driven by UVB - so in winter at low elevations, the UV index is often low.

Two important exceptions to the "low winter UV index means low risk" assumption:

• Altitude - UV intensity increases by approximately 10-12% per 1,000 metres of elevation. At the top of a ski slope at 2,000-3,000 metres, UV exposure can be considerably higher than at sea level on a summer day, even when the temperature is well below freezing.
• Snow reflection - Fresh snow reflects up to 80% of UV radiation back upward, effectively nearly doubling UV exposure compared to non-reflective surfaces. This means you are receiving UV from both above and below simultaneously.

For winter sports, SPF 50+ is not optional. The combination of high altitude and snow reflection creates UV exposure conditions that significantly exceed a typical summer day at sea level.

Skin damage in the colder months

UV is not the only environmental factor affecting skin in winter. Cold temperatures, low humidity, dry air and harsh winds increase transepidermal water loss, depleting the skin's natural moisture and lipid content. The result is a weakened barrier that is more vulnerable to UV-induced stress, inflammation and irritation.

Research confirms the impact: a 2021 study documented the detrimental effects of cumulative UVA radiation on skin DNA, contributing to reactive oxygen species (ROS) formation that damages collagen and elastin - the structural proteins responsible for skin firmness and resilience. This process does not pause in winter.

The combination of a cold-weather-compromised barrier and ongoing UVA accumulation is why winter skincare should prioritise two things together: barrier support and broad-spectrum SPF. Each makes the other more effective.

Choosing your winter SPF

The criteria for a good winter sunscreen are identical to the criteria for a good summer sunscreen - because the UV you are primarily protecting against (UVA) does not change seasonally.

What to look for

• SPF 50+ - for daily use year-round. Using the same product throughout the year removes the temptation to reduce protection in months that feel less sunny
• PA++++ or EU UVA circle logo - verified broad-spectrum UVA coverage. SPF alone measures only UVB
• Fragrance-free - particularly important in winter when the barrier is more vulnerable
• Hydrating or skin-supportive formulation - in winter, a formula that supports rather than dries the skin makes daily use more comfortable and consistent
• Lightweight enough to wear daily - the most effective sunscreen is the one you apply correctly every day

How SPF numbers work

SPF 50 blocks approximately 98% of UVB rays. SPF 30 blocks approximately 96.7%. That difference looks small as a percentage, but SPF 30 allows about 65% more UVB to reach the skin than SPF 50 - a meaningful gap for daily cumulative exposure over months and years. In winter the UVB risk is lower, but using a consistent SPF 50+ means you are protected during any unexpectedly high-UV day without needing to adjust.

The barrier connection

Winter skin and SPF work together more than most skincare routines acknowledge. A healthy, well-hydrated barrier absorbs and responds to UV radiation differently than a compromised one. Barrier-weakened skin is more reactive, more prone to post-UV inflammation, and less able to manage the oxidative stress that UV exposure produces.

The winter skincare approach that works best for long-term skin health combines:

• A rich moisturiser or facial oil in the evening to replenish lipids depleted by cold and dry air
• A hydrating, barrier-supportive serum under SPF in the morning
• SPF 50+ with verified UVA coverage as the final morning step, every day

Vitamin D is worth mentioning here too. The concern that daily SPF depletes vitamin D is not supported by the evidence - most people do not apply sunscreen uniformly enough to block vitamin D synthesis entirely, and even small areas of unprotected skin are sufficient for most people's needs. Year-round supplementation is a more reliable approach for anyone concerned about vitamin D levels.

Frequently Asked Questions

© NAYA Skincare. All information is for educational purposes and does not constitute medical advice.