By Jennelle Daly, Founder, PA Aesthetic & Functional Medicine Provider at Limitless Aesthetics & Wellness

If sunscreen disappears from your routine once winter arrives or when you’re spending most of your day indoors, you’re not alone. Many people associate sun damage with hot summer days and outdoor activities, not office lighting, car rides, or sitting near a window. Unfortunately, this common misconception may be quietly accelerating skin aging and pigmentation issues even more than the summer sun you try so hard to avoid.

The truth is we are exposed to harmful UV rays year-round, even indoors. In particular, UVA rays are present 365 days a year and can penetrate clouds, overcast skies, and even glass. That means sitting near windows, commuting in your car (yes, even as the passenger), or running quick errands all add up to cumulative exposure. Winter does not provide a break from UV light —it’s just sneakier, as it hides behind gloomy skies.

Understanding the difference between UVA and UVB rays is key. UVB rays are responsible for sunburns and tend to be stronger in the summer months. UVA rays, however, penetrate deeper into the skin and are the primary drivers of premature aging, collagen breakdown, skin laxity, and pigmentation issues like melasma. UVA exposure also causes “photoaging,” which we routinely correct in-office with treatments such as BBL (BroadBand Light), Moxi, and RF microneedling. Without proper sun protection, even in winter, UV exposure can undo the progress of these corrective treatments.

This is why sunscreen remains one of the most important anti-aging and skin-protective products you can use, regardless of season or setting. Sunscreen helps prevent cellular damage, pigment worsening, and collagen loss, all of which become more noticeable over time.

Another often-overlooked factor is blue light exposure. Many of us spend hours each day in front of screens, whether for work or leisure. Certain modern sunscreens now offer protection against visible and blue light, which is especially helpful for patients prone to pigmentation or melasma. Tinted mineral sunscreens are a great option because they provide broad-spectrum UV protection while also acting like lightweight makeup. My patients love that these formulas don’t feel thick or tacky like traditional zinc sunscreens, which improves daily compliance.

So, what SPF should you choose? For most people who are primarily indoors, SPF 30+ is sufficient and blocks about 97% of UVB rays. If you plan to be outdoors for more than 30 minutes, have hyperpigmentation concerns, melasma, or have recently undergone laser treatments, I recommend increasing your usage to SPF 50+.

As for reapplication indoors, it’s not always necessary, especially if you’re not pigment-prone, haven’t had recent treatments, and aren’t near windows with indirect sunlight. However, if you plan to step outside before the sun goes down, reapplying every 4-6 hours is advised, even if that exposure is brief. Fortunately, there are convenient, indoor-friendly reapplication options available, such as tinted compacts, roll-on sticks, and mineral powders that fit seamlessly into your daily routine.

Sunscreen isn’t just for summer, and it’s not just for outdoors. Consistent, year-round protection is one of the simplest and most effective investments you can make in your skin’s long-term health and appearance.