Natural Sciences Active Updated Jul 28, 2026
The body's hidden light detectors
For decades opsins were assumed to exist only so the eye can see, but researchers keep finding melanopsin, encephalopsin and neuropsin in skin, blood vessels and immune cells, where they appear to track daylight rather than form images. The stakes are whether this non-visual light sensing turns out to shape human mood, circadian rhythm, metabolism and fat storage, and whether doctors start factoring light exposure into treatment as a result.
The story so far
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Jul 28, 2026 Latest
Knowable Magazine reported that opsins, the light-sensitive proteins long thought to exist only for vision, also turn up in human skin, blood vessels and immune cells, with the strongest evidence so far linking them to mood regulation and the body's daily rhythms and early studies hinting at roles in fat storage, metabolism and eye development.
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