The science on whether genuine smiles can be voluntarily produced.
The short answer is: mostly no, and trying usually makes it worse. The long answer involves fascinating neuroscience, the limits of voluntary muscle control, and what this means for anyone trying to look their best in photos.
The key muscle in a Duchenne smile is the orbicularis oculi — the ring of muscle surrounding the eye socket. When you genuinely smile this muscle contracts involuntarily, raising the cheeks and creating the crow's feet wrinkles that make smiles look real.
The problem is that most people have very limited voluntary control over this muscle. Guillaume Duchenne himself described it as the muscle that "only puts itself into play by the sweet emotions of the soul." You cannot simply decide to crinkle your eyes authentically any more than you can decide to blush.
Machine learning models trained on facial action coding can distinguish genuine from posed smiles with approximately 86% accuracy — significantly better than untrained human observers at around 70%. This suggests that the differences between real and fake smiles are objectively measurable, not just subjectively felt.
AI research identified that one of the most reliable fake smile indicators is timing — how quickly the smile appears and disappears. Genuine smiles build gradually and fade gradually. Posed smiles often appear suddenly and switch off abruptly. This temporal pattern is very difficult to fake consciously.
Genuine smiles are slightly asymmetric because different muscles on each side of the face contract at slightly different rates. Posed smiles tend to be more symmetrical because people consciously try to look "correct." Ironically, too much symmetry signals inauthenticity.
Research does show that some people can produce convincing Duchenne-like smiles voluntarily. These tend to be trained actors, people with high emotional granularity (the ability to precisely identify and recall specific emotions), and a small percentage of people with unusual voluntary control over their orbicularis oculi.
However even trained actors typically use emotional recall — triggering genuine memories of happiness to produce authentic-looking expressions — rather than pure muscle control. The most reliable way to get a genuine smile is to actually feel genuine happiness.
For most people, trying to consciously fake a Duchenne smile produces results that are worse than simply smiling naturally. The effort of trying creates additional tension and self-consciousness that makes expressions look even more strained.
The better approach is to engineer genuine happiness — through humor, positive memories, or genuine connection with whoever is taking your photo — rather than trying to manufacture the expression directly. Genuine emotion produces genuine expression.
Our guides cover science-backed techniques for natural photo expressions.
For most people no — at least not convincingly. The key eye muscle in a genuine Duchenne smile is largely involuntary and cannot be activated at will without genuine positive emotion. AI can now detect fake smiles with 86% accuracy.
Posed smiles in photos are usually non-Duchenne — they only involve mouth muscles, not eye muscles. The solution is not to try harder to fake a smile but to trigger genuine positive emotion through humor, memory recall, or genuine engagement with whoever is taking your photo.
Trained actors are better at it than most people, but even professional actors typically use emotional recall rather than pure muscle control. They think of something genuinely funny or happy to produce authentic-looking expressions.
AI models analyze multiple factors simultaneously including eye muscle involvement, smile timing and duration, facial symmetry, and the relationship between mouth and eye movements. They can detect these patterns with around 86% accuracy, better than untrained human observers.