Cataracts cause a gradual clouding of vision that many people don’t notice until age 60 or later, even though the proteins in your eye’s lens start breaking down around age 40. The changes are slow enough that you may not realize your vision has shifted until everyday tasks like reading or driving at night become noticeably harder. There’s no reliable way to diagnose cataracts at home, but several telltale symptoms can signal it’s time for an eye exam.
The Most Common Warning Signs
A cataract forms when the naturally clear lens inside your eye turns cloudy. That clouded lens scatters and blocks light before it reaches the back of your eye, so instead of a sharp image, you get a blurry one. The effect is similar to looking through a foggy or dirty window.
The symptoms tend to creep in rather than appear suddenly:
- Blurry or hazy vision that doesn’t improve with blinking or rubbing your eyes
- Fading or yellowing colors, where whites may look dingy and bright colors lose their punch
- Trouble seeing at night, especially difficulty judging distances or seeing clearly in dim lighting
- Glare and halos around lights, particularly from oncoming headlights or bright sunlight
- Needing brighter light for reading, cooking, or other close-up tasks
- Frequent prescription changes in your glasses or contacts
- Double vision in one eye, which can happen when a cataract scatters light unevenly across the lens
You might notice just one or two of these at first. Many people’s earliest complaint is that night driving has become uncomfortable because of glare from streetlights and headlights. Others first notice that colors look washed out, or that they need to hold a book closer to a lamp to read.
Why Symptoms Vary by Cataract Type
Not all cataracts produce the same experience, because the cloudiness can develop in different parts of the lens. The three most common types each have a signature pattern.
A nuclear cataract forms in the center of the lens. It develops slowly over years as the core hardens and turns yellow, then brown. In the early stages, it can actually make you temporarily more nearsighted, which some people experience as a brief improvement in reading vision (sometimes called “second sight”). As it progresses, colors become harder to distinguish and overall vision gets cloudier.
A cortical cataract starts in the outer edges of the lens and works inward. Glare is typically the dominant symptom, especially from headlights while driving at night. How much it affects your vision depends on how close the cloudy areas are to the center of your visual field. You may also notice reduced contrast, where objects seem to blend into their backgrounds.
A posterior subcapsular cataract forms at the back surface of the lens. This type tends to progress faster than the others and often causes problems with reading and bright-light glare earlier on. It’s more common in people who use corticosteroid medications or have diabetes.
How Cataracts Differ From Other Eye Conditions
Several age-related eye conditions share overlapping symptoms, so it’s worth understanding what sets cataracts apart. Glaucoma, for instance, also causes halos around lights, but its hallmark is a gradual loss of peripheral (side) vision that often goes completely unnoticed until it’s advanced. Cataracts, by contrast, affect the overall clarity and brightness of what you see rather than shrinking your visual field.
Macular degeneration targets your central vision specifically. If you notice a dark or blank spot right in the middle of what you’re looking at, or if straight lines appear wavy or distorted, that pattern points more toward macular degeneration than cataracts. Cataracts produce a general haziness or film over your entire visual field, not a localized blind spot.
It’s also possible to have more than one of these conditions at the same time, which is one reason a professional exam matters more than symptom-matching at home.
What Happens During a Cataract Eye Exam
Only an eye doctor can confirm whether you have cataracts. The exam is straightforward, painless, and usually takes under an hour. It typically includes three core tests.
First, a visual acuity test: the standard eye chart reading, one eye at a time, to measure how sharp your vision is and whether your current prescription still works. Second, a slit-lamp exam, where the doctor uses a specialized microscope with a bright, narrow beam of light to examine the structures inside your eye in fine detail. This is the test that can directly reveal a cloudy lens. You’ll likely get eye drops to dilate your pupils beforehand, which makes it easier to see the lens and the nerves at the back of your eye. Third, the doctor may measure the pressure inside your eye, which helps rule out glaucoma at the same time.
You may also be asked to fill out a questionnaire about how your vision affects daily activities like driving, reading, or recognizing faces. This helps your doctor gauge whether a cataract, if present, has progressed enough to warrant treatment.
A Simple Self-Check You Can Do Now
There’s no home test that can diagnose a cataract, but a quick comparison can help you decide if an exam is worthwhile. Cover one eye and look at a page of text, then switch. Cataracts often develop unevenly between the two eyes, so you may notice one side is noticeably hazier or dimmer than the other. Try the same thing at night with a distant light source: if you see a starburst or halo with one eye but not the other, that’s worth mentioning to an eye doctor.
Pay attention to color too. Look at a white wall or sheet of paper with each eye separately. If one eye makes the white appear more yellow or brownish, that’s a classic sign of a nuclear cataract changing how light filters through your lens.
These checks can flag a problem, but they can’t tell you the cause. A slit-lamp exam is the only way to see the lens directly and confirm what’s going on.
Who Gets Cataracts and When
Cataracts are overwhelmingly an age-related condition. In the U.S., nearly 1 in 5 people between ages 65 and 74 have cataracts that affect their vision. By age 80, more than half of people either have cataracts or have already had surgery to remove them.
Several factors can speed up the timeline. Diabetes accelerates lens clouding, sometimes significantly. Long-term use of corticosteroid medications (for asthma, arthritis, or autoimmune conditions) raises risk as well. Heavy alcohol use, smoking, prolonged sun exposure without UV-protective sunglasses, and a history of eye injury or eye surgery all contribute. If any of these apply to you and you’re noticing vision changes, that context makes an eye exam more urgent.
What to Expect if You Do Have Cataracts
An early cataract diagnosis doesn’t mean you need surgery right away. Many people live with mild cataracts for years, managing with updated glasses prescriptions, anti-glare coatings, and brighter lighting at home. The decision to operate is typically driven by how much the cataract interferes with your daily life rather than by how it looks on an exam.
When cataracts do reach the point where stronger glasses no longer help and activities like driving or reading become genuinely difficult, surgery is the only effective treatment. It’s one of the most commonly performed procedures in the world: the clouded lens is removed and replaced with a clear artificial one. Most people notice dramatically sharper vision within days, and serious complications are rare.
The key takeaway is that cataracts develop gradually and give you time to act. If you’re experiencing any combination of blurry vision, glare sensitivity, faded colors, or worsening night vision, a comprehensive eye exam can give you a definitive answer and a clear picture of what comes next.