Have you ever stepped out into the sun or turned on a bright lamp and found yourself sneezing? You are not alone. This reaction, known as the photic sneeze reflex, happens when light triggers an involuntary sneeze. It is a common experience for many people, but it is not always easy to measure accurately.
A large review of 15 different study groups found that about 22% of healthy individuals experience this reflex. While this gives us a general idea of how common the condition is, the researchers noted that the data comes from studies with very different methods and definitions. Because each study measured things differently, the results can vary quite a bit.
Because the original studies were often inconsistent, we should view this 22% figure as a broad summary rather than a precise number for everyone. The evidence is currently considered to have low certainty because of these differences in how the reflex was tracked and defined.
