Do your eyes age faster than the rest of your body?

The lens of your eye is probably the most vulnerable part of your entire body when it comes to ageing. The cells deep inside the lens lack a cell nucleus and cannot renew themselves. That means the proteins in those cells literally have to last a lifetime. Once those proteins clump together or become cloudy, a cataract forms. This is not a coincidence, but a direct consequence of this unique structure.

The retina also shows signs of ageing early on. In the ageing retina, harmful substances accumulate: metabolic waste products, low-grade chronic inflammation and weakened mitochondria (the cell's energy factories). The collaboration between the light-sensitive cells and the underlying support layer (the retinal pigment epithelium) falls out of balance. This creates the conditions for macular degeneration, the leading cause of blindness in the Western world. Genetic predisposition also plays a major role here: people with two risk copies of a particular variant in the gene that regulates the immune system have a 7.4 times greater chance of developing macular degeneration than people without that variant.

Research using AI models applied to protein profiles from eye fluid reveals something remarkable: even eye diseases that are not normally considered 'age-related' are associated with accelerated molecular ageing of specific eye cell types. This suggests that some eye cells age faster than you would expect based on your actual age.

That the eye occupies a special position in the ageing process is also evident from the eyelids. The small glands within them (meibomian glands), which produce a thin layer of oil over your tears, shrink over the years. Stem cell exhaustion is the underlying cause. The result is more frequent dry eyes, a complaint that increases sharply with age.

Finally, the retina acts as a kind of window onto the ageing of the brain. An AI-based measure of retinal ageing, calculated from ordinary eye photographs, was linked in a large study (more than 33,000 people, followed over 12 years) to a 25 to 43% greater chance of dementia. Whether the retina here follows the brain or instead provides an early signal is not yet certain, but the association is strikingly consistent.