Yes, cataracts are a normal part of aging. The proteins inside your eye’s lens gradually break down over decades, and by age 60 and older, more than half of all people have some degree of cataract formation. About 17% of people between ages 40 and 59 already show early signs. Having a cataract doesn’t automatically mean you need surgery, but understanding what’s happening in your eyes helps you recognize changes and know when to act.
Why the Lens Breaks Down Over Time
Your eye’s lens is made of tightly packed proteins called crystallins, and unlike most cells in your body, the ones in the center of the lens are never replaced. The proteins you’re born with are the same ones you carry for life. Over decades, those proteins accumulate damage from UV radiation, oxidation, and other chemical changes. This damage destabilizes the proteins, causing them to partially unfold and clump together into insoluble clusters that scatter light instead of letting it pass through clearly.
Oxidative damage is considered a major driver of this process. As the proteins unfold, they expose sticky surfaces that were previously buried inside their structure. Those exposed surfaces latch onto neighboring proteins, forming larger and larger clumps. The result is the cloudy or opaque patch we call a cataract. Because this protein damage builds up gradually and continuously, some degree of lens clouding is virtually inevitable if you live long enough.
How Common Cataracts Are by Age
A comprehensive global meta-analysis found that roughly 17% of people aged 40 to 59 have some form of cataract. After age 60, that number jumps to about 54%. The increase is steep because the protein damage described above accelerates as your natural antioxidant defenses weaken with age.
Not all cataracts are the same, though. The three main types affect different parts of the lens and show up at different rates:
- Nuclear cataracts form in the center of the lens and are the most common type after 60, affecting about 31% of people in that age group. They tend to cause distance vision to blur first while temporarily improving close-up reading vision, a phenomenon sometimes called “second sight.”
- Cortical cataracts develop in the outer edges of the lens and affect roughly 25% of people over 60. They often cause problems with glare.
- Posterior subcapsular cataracts form at the back surface of the lens and are less common, affecting about 7% of people over 60. They tend to progress faster and interfere with reading and bright-light vision early on.
Early Symptoms to Watch For
Cataracts often develop so slowly that you won’t notice anything at first. The clouding may start in a small area of the lens and not affect your overall vision. Over time, though, the changes become harder to ignore. Common early signs include blurred or dim vision, increased sensitivity to light and glare, seeing halos around lights, needing brighter light for reading, and colors appearing faded or yellowed. Some people notice double vision in one eye or find themselves needing new glasses prescriptions more frequently.
Trouble seeing at night is another hallmark. You might notice oncoming headlights feel more blinding than they used to, or streetlights seem to have a starburst quality. These symptoms typically worsen gradually over months or years rather than appearing suddenly.
What Speeds Up the Process
While aging is the primary cause, several factors can accelerate lens damage and bring on cataracts earlier or make them progress faster.
Smoking is one of the strongest modifiable risk factors. Free radicals from cigarette smoke directly damage lens proteins and cell membranes while also lowering your body’s circulating antioxidants. Toxic metal ions and cadmium from smoke accumulate in the lens over time. Smoking is particularly linked to nuclear and posterior subcapsular cataracts.
Diabetes significantly raises your risk as well. High blood sugar creates osmotic stress inside the lens through a buildup of sorbitol, a sugar alcohol. This makes people with diabetes especially prone to cortical cataracts, and they also face higher rates of surgical complications when cataracts eventually need treatment.
UV exposure matters too. Cumulative sun exposure over years contributes to the oxidative damage that destabilizes lens proteins. Genetics also play a role: your susceptibility to environmental damage is strongly influenced by inherited risk factors. If your parents developed cataracts early, you may be more likely to as well.
Can You Slow Cataract Formation?
You can’t prevent cataracts entirely, but dietary choices appear to make a meaningful difference in timing. A systematic review of the evidence found that people with the highest intake of lutein or zeaxanthin, pigments found in leafy greens, eggs, and corn, had a 19% lower risk of developing age-related cataracts compared to people with the lowest intake. At higher doses (around 10 mg per day of lutein or zeaxanthin), the risk reduction reached 26%.
Beta-carotene, found in carrots, sweet potatoes, and other orange vegetables, showed a 10% risk reduction at higher intake levels. These nutrients act as antioxidants inside the lens, helping to counteract the oxidative damage that drives protein clumping. Beyond diet, wearing UV-blocking sunglasses consistently and not smoking are the two most impactful lifestyle choices for protecting your lenses.
When Cataracts Need Treatment
Many people live with early cataracts for years without needing any intervention. Updated glasses, better lighting, and anti-glare coatings can manage symptoms for a long time. Surgery becomes the right choice when cataracts interfere with your daily life: difficulty reading, watching television, driving safely, or doing your job. The American Academy of Ophthalmology emphasizes that functional impact, not a specific test number, is the main reason for surgery. The inability to carry out activities you need or want to do is what tips the balance.
Other less common triggers for surgery include double vision in one eye caused by the cataract, or situations where the clouded lens is raising pressure inside the eye.
What Surgery Looks Like
Cataract surgery is one of the most commonly performed and successful procedures in medicine. The clouded lens is broken up with ultrasound and removed through a tiny incision, then replaced with a clear artificial lens. About 90% of people achieve good functional vision afterward, and in eyes without other conditions, more than 95% reach that outcome.
The procedure typically takes under 30 minutes and is done as an outpatient. Recovery is generally quick, with most people noticing clearer vision within a few days, though full healing takes several weeks. Complication rates increase with age, with older patients facing slightly higher risks of issues like capsule rupture during surgery, infection, or corneal swelling, but the overall safety profile remains strong even for very elderly patients.
Globally, cataracts remain the leading cause of blindness, responsible for about 40% of all blindness worldwide, primarily in regions with limited access to surgery. In countries where surgery is readily available, cataracts are a highly treatable condition rather than a permanent loss.