A routine photo of the back of the eye may one day tell doctors something they never expected: how strong or fragile a person’s bones are becoming.
Two large population studies, one in Singapore and one in the United Kingdom, have found that the rate at which a person’s retina appears to be aging is meaningfully linked to their risk of developing osteoporosis. The research, led by scientists at the Singapore Eye Research Institute, suggests that something visible inside the eye may reflect what is quietly happening inside the skeleton.
Osteoporosis affects nearly 20% of the global population. It causes a gradual, symptom-free loss of bone mineral density that can leave bones brittle and prone to fracture. It is especially prevalent among postmenopausal women and older adults, and the consequences of a fracture particularly in the hip or spine can be severe and, in some cases, fatal.
One of the condition’s most persistent challenges is that it is often diagnosed too late. Bone density scans, the standard detection tool, are frequently not recommended until a person over a certain age has already fractured a bone. By that point, the window for meaningful prevention through diet changes, increased physical activity or other interventions may have already narrowed significantly.
That is precisely why researchers are looking for earlier, easier and less invasive ways to identify those at risk.
Why the eyes hold so many health clues
The retina is uniquely positioned to offer insights into the body’s internal state. As the only outward extension of the central nervous system, it is one of the few places where nerves, blood vessels, inflammatory markers and metabolic signals can all be observed without any invasive procedure. In recent years, researchers have found that signs deep within the retina may point to cardiovascular risk, cognitive decline and accelerated aging more broadly.
Building on that work, researchers trained an artificial intelligence model called RetiAGE using nearly 130,000 retinal images from more than 40,000 participants in a South Korean health study. The model was designed to assess how quickly a person’s retina appears to be aging relative to their chronological age.
That model was then applied to two separate populations to test whether retinal aging could predict bone health outcomes over time.
What the 2 studies found
In a Singapore study of nearly 2,000 adults, researchers found that the older a retina appeared according to RetiAGE’s markers, the lower the participant’s bone mineral density tended to be.
In a UK Biobank study of nearly 44,000 participants, the same team found that a higher RetiAGE score was associated with a greater risk of developing osteoporosis over time even after accounting for age, sex, body mass index, physical activity, smoking status and cardiovascular health.
In that UK dataset, each standard deviation increase in the RetiAGE score was associated with a 12% higher risk of osteoporosis overall. Among men specifically, that figure climbed to 25% a notable finding given that osteoporosis is far more commonly diagnosed in women.
Why the eyes and bones may be so closely connected
On the surface, the eyes and the skeleton seem like distant biological neighbors. But researchers point to several overlapping mechanisms that could explain the link.
Both systems benefit from the same lifestyle factors regular physical activity, a nutrient rich diet and adequate sunlight exposure meaning that when one is aging well, the other often is too. There also appear to be shared genetic factors. A gene that regulates immune cells within the eye is also involved in producing key bone cells. Beyond that, vascular and inflammatory dysfunction can damage both eye tissue and bone structure simultaneously. Hypertension, for example, has been associated with reduced bone turnover, and v is something an optometrist can detect during a standard retinal exam.
A 2018 study in South Korea added further context, finding that osteoporosis was linked to age related macular degeneration though in that research, the association was observed only among women.
What this could mean for early screening
RetiAGE is not a comprehensive diagnostic tool, and the researchers are careful to say so. The model captures only some markers of retinal aging, and the studies demonstrate association, not causation. But the consistency of findings across two distinct and very large populations is difficult to dismiss.
The researchers argue that retinal photos already widely taken during routine eye exams could be an accessible, low cost and repeatable way to flag people who may be developing osteoporosis before they ever fracture a bone or qualify for a traditional bone density scan.
For a condition that tends to progress silently until something breaks, that kind of early warning could make a meaningful difference.
