Does Smiling Make You Look Younger? What Research and AI Data Show

Multiple peer-reviewed studies have examined the relationship between smile expression and apparent age. A notable 2019 study by Ganel and colleagues found that smiling faces are consistently rated as younger than neutral faces of the same person by independent observers — a finding robust across different face types, ages, and cultural contexts.

The mechanism is structural: a genuine smile raises the midface — the cheeks and the zone below the eyes — producing a lifted facial geometry that is structurally associated with youth. Midface descent (the gravitational lowering of this zone over time) is one of the primary markers of facial aging. A genuine smile partially reverses this signal by muscularly lifting the midface back to a more youthful position.

AI age estimation tools — which are trained on human apparent age ratings — pick up the same signal. Photos with genuine smiles consistently receive younger apparent age estimates than the same face in neutral expression, all else equal. The AI is reading the same midface lift that human observers respond to.

The youthful effect of smiling is driven primarily by three mechanisms. First, the zygomatic major — the primary smile muscle — pulls the mouth corners upward and the cheeks outward and upward, producing midface elevation. This muscular lift produces the same visual geometry as the naturally higher midface position of younger faces.

Second, the orbicularis oculi in a genuine Duchenne smile raises the lower eyelids and lifts the cheek zone directly below the eye — the under-eye area that typically shows increasing hollowing with age. The genuine smile partially fills in this hollow through muscle action, reducing the under-eye depth signal that AI models associate with aging.

Third, a genuine smile signals positive affect and energy — signals that observers unconsciously associate with youth and vitality. The expression communicates a psychological state that reads as younger even beyond its geometric effects.

The youthful effect of smiling is substantially larger for genuine Duchenne smiles than for posed smiles — and for some individuals, a tense, effortful posed smile can actually increase apparent age by producing facial tension lines.

A posed smile activates mainly the zygomatic major (mouth corners up) without the orbicularis oculi (eyes neutral). This produces the midface lift effect but not the under-eye filling effect. More importantly, the muscle tension of maintaining a forced smile creates strain lines around the mouth and eyes that can offset the lifting benefit.

A genuine Duchenne smile activates both muscles fully — zygomatic major plus orbicularis oculi — producing both lifting effects simultaneously with natural, relaxed muscle engagement rather than tension. This is why the memory technique (triggering a genuine smile through emotional recall rather than performance) produces a more youthful-reading result than trying to force a smile for a photo.

The magnitude of the age-reducing effect of smiling varies across studies and individuals, but the research consensus suggests that a genuine smile can shift apparent age ratings by one to four years on average — with larger effects in older faces (where midface descent has progressed further) and smaller effects in younger faces (where the structural aging signals are less pronounced).

AI age estimation data from Smile Tracker is consistent with this range. Comparing the same face in genuine smile versus neutral expression consistently produces younger readings in the smile condition — typically two to five years for well-lit, well-positioned photos, and sometimes more in cases where the neutral expression involves significant brow tension or jaw tension.

Combined with the lighting effect (soft frontal lighting reducing apparent age by five to eight years versus overhead lighting), the combined impact of good lighting and a genuine smile can shift AI apparent age estimates by a total of seven to twelve years relative to the worst-case conditions — overhead lighting and a tense neutral expression.

Smiling is not the only expression with an aging effect. Brow tension — a furrowed or raised brow from concentration or anxiety — adds apparent years by producing forehead lines and compressing the upper face. Developing the habit of consciously relaxing the forehead (particularly before photos and video calls) removes this aging signal.

Jaw tension similarly adds apparent age by producing a tighter, harder-looking lower face that reads as stress and fatigue. The exhale-and-release technique — slow breath out through the mouth before a photo or important interaction — resets jaw tension and produces a softer, more youthful lower face.

Habitual resting expression also matters over the long term. A slightly downturned resting expression (driven by depressor anguli oris resting tone) allows gravitational descent signals to show more clearly. A softly neutral to slightly upturned resting expression maintains midface elevation passively and reads as younger in aggregate — one reason people who smile frequently tend to look younger than their chronological age over time.

The most direct way to measure how much smiling affects your apparent age is to test it objectively. Upload two photos taken under identical conditions — same lighting, same angle, same camera — one with a neutral expression and one with your best genuine smile. Compare the Guess My Age readings for both.

For the most meaningful test: use frontal window lighting, portrait mode at arm's length, and the memory technique for the smile photo to ensure you are comparing genuine smile versus neutral rather than posed smile versus neutral. The difference in apparent age readings gives you a precise, personal measure of how much your specific smile expression affects your apparent age.

Most people find the effect larger than expected. The combination of midface lift, under-eye filling, and the vitality signal of a genuine expression adds up to a significant youth shift — and it is entirely repeatable any time you want it.