Most of the eye conditions I treat become more common with age. That is why I found this research interesting: scientists studied the eyes of the Greenland shark, the longest-living vertebrate known, with some individuals thought to survive for around 400 years. The work was led by Dorota Skowronska-Krawczyk at the University of California, Irvine, and published in Nature Communications.
A shark long thought to be nearly blind
Greenland sharks live in very dark, cold Arctic waters, and parasites are often attached directly to their eyes. For those reasons, scientists suspected they might be functionally blind. Skowronska-Krawczyk noticed in video footage that the sharks moved their eyes toward light, which prompted a closer look.
What the researchers found
- The sharks studied were caught between 2020 and 2024 near the University of Copenhagen’s Arctic Station in Greenland, and their eyes were preserved for analysis.
- The team found no evidence of cell death in the retina.
- Rhodopsin, a protein needed for vision in dim light, remained active and was tuned to blue light, which may help the sharks see in the faint light deep in Arctic waters.
- The findings suggest a DNA repair mechanism may help preserve the sharks’ vision for centuries without signs of retinal degeneration.
Why eye researchers care
The researchers hope that understanding how these eyes stay healthy could eventually point toward new ways to prevent age-related vision loss, and help guide research into conditions including macular degeneration and glaucoma. This is basic science in an animal, though. It does not offer a treatment, and it will take years of research to learn whether any of these mechanisms apply to people.
What you can do now for aging eyes
- Have a comprehensive dilated eye exam on the schedule your eye doctor recommends, especially after age 40.
- Do not smoke, protect your eyes from strong sunlight, and keep blood pressure and blood sugar under control.
- Report changes such as distortion, new floaters, or loss of side vision promptly.
For more plain-language reading on vision as we age, see bettereyesightatanyage.com.
Source: This shark can live 400 years. Its eyes barely seem to age (ScienceDaily (University of California, Irvine), 08/21/2026). This article is an educational summary written by Khanna Vision Institute and is not a substitute for medical advice.