Wrinkles on only one side of the face: why?

If one side of your face looks more lined than the other, it is rarely a sign that something is wrong. It usually means that side has simply had more of the things that cause wrinkles: more sun, more pressure, or more muscle activity over the years. Here is what is behind it and what can even things out.

A degree of facial asymmetry is completely normal, by the way. Almost no one is perfectly symmetrical, and a quick photo of each side will usually show small natural differences. If lines bother you, treatments such as anti-wrinkle injections can be used to rebalance them.

The everyday causes

Uneven sun exposure

This is the big one. If one side regularly gets more UV, for example the window side when you drive a lot, that side ages faster, because UV is the main driver of photoageing. Studies of long-term drivers often show more sun damage on the window side of the face. Daily SPF on the whole face, including in the car, helps prevent this widening over time.

Sleep position

Repeatedly sleeping pressed into the pillow on one side creates “sleep wrinkles” from sustained pressure on the same areas, as the AAD explains. Over years, those creases can set. Sleeping on your back, or at least alternating sides, reduces it.

Habitual muscle use

Favouring one side when you chew, a stronger smile or squint on one side, or always holding a phone against the same cheek, all work the muscles and skin on that side more, which can deepen lines there.

Natural asymmetry

Underlying bone structure and muscle balance differ slightly between the two sides for everyone, which can make one side simply more prone to showing lines.

What helps going forward

A few simple changes slow uneven ageing:

• Apply SPF daily to the whole face, and consider a UV-protective film on a car window if you drive a lot.
• Sleep on your back where you can, or switch sides.
• Alternate the side you hold your phone to.
• Use proven topicals (a retinoid, vitamin C) evenly across both sides.

Evening out set lines

Where the difference is already established, in-clinic treatments can rebalance the two sides:

• Anti-wrinkle injections can relax an overactive muscle on the more-lined side.
• Dermal fillers can restore volume where one side has lost more.
• Resurfacing such as microneedling, peels or laser improves texture and tone.

Because this is about balancing one side against the other, it really benefits from an experienced eye. A good practitioner will assess your face with photographs and treat to your specific asymmetry rather than applying a generic plan, as the Mayo Clinic’s overview of wrinkle causes and sensible clinical practice both support.