Do sunglasses prevent wrinkles and crow's feet? Two ways, and one of them is squinting

Yes, sunglasses reduce wrinkles around the eyes, through two separate mechanisms. The first is squinting: crow's feet are expression lines, made by the skin at the outer corner of the eye folding every time you narrow your eyes against bright light, and a pair of sunglasses removes the reason to squint. The second is ultraviolet: UV exposure is the main cause of skin ageing, the skin around the eyes is the thinnest on the face, and a lens large enough to cover that area shades it. Both effects are real and both depend on the frame covering the eye area, not just the eye.

Mechanism one: squinting

Facial expressions crease the skin. Repeat the same expression tens of thousands of times over years and the crease becomes permanent. Frown lines come from frowning; crow's feet come from the muscle around the eye contracting, which happens when you smile and when you squint.

Squinting in bright light is involuntary and constant. On a bright day without sunglasses, you do it every time you look up, look at water, look at a pale wall. Sunglasses remove the trigger. That is the single largest thing they do for the skin around the eyes, and it is why dermatologists list sunglasses under wrinkle prevention alongside sunscreen.

Polarized lenses help here beyond plain tinted ones, because glare, the thing that makes you squint hardest, is what polarization removes. Our polarized vs non-polarized post covers the difference.

Mechanism two: UV on thin skin

Ultraviolet breaks down collagen and elastin, the fibres that keep skin firm, and it does it cumulatively over a lifetime. Dermatologists call the result photoageing: fine lines, deeper wrinkles, uneven pigment, loss of elasticity. It is the main cause of visible skin ageing, ahead of chronological age.

The skin around the eyes is the thinnest on the face, has little fat beneath it, and shows photoageing first. It is also awkward to sunscreen; product near the eye stings, and many people skip it.

A sunglass lens that sits close and covers the whole eye socket shades that skin. It is not sunscreen and it does not replace sunscreen elsewhere on the face, but for the area directly behind the lens it is an effective physical block, and it is one you will actually wear.

What kind of frame does this

Both mechanisms depend on coverage. A small lens that leaves the outer corners of the eyes exposed does less for squinting, because peripheral glare still gets in, and nothing for the skin it does not cover.

• Lens height matters. A lens 45mm or more tall covers the socket; a shallow fashion lens does not. Ours is 50mm.
• Lens width and frame width matter. The frame should reach the outer corner of the eye. Our T01 has 60mm lenses on a 140mm front, which is wide; our measurements post explains the numbers.
• Closeness matters. A frame that sits off the face lets light in from the sides and from below. Wrap styles cover most; a flat frame like ours covers the front well and the sides less. A hat with a brim closes the gap from above.
• UV blocking is the point. Shade without UV blocking still lets the ageing wavelengths through. Look for a stated UV claim; ours is a UV-protective coating, stated on every product page with its limits.

What sunglasses do not do

• Replace sunscreen. The forehead, cheeks and nose are still in the sun. Sunscreen there, every day, is the other half.
• Reverse existing lines. Prevention only. Existing crow's feet do not fade because you stop squinting.
• Cover the area if the lens is small. A tiny lens is a fashion choice, not a skin one.

Frequently asked questions