Your eye is made up of different parts, and all of them play an important role in your vision. The lens is part of the eye that sits behind the iris, the coloured part of your eye. The lens is a clear structure that focuses the light that enters your eye so that your brain can process images. But what causes cataracts?
Key takeaways:
- Cataracts are caused by protein breakdown inside the lens of the eye
- Common causes of cataracts include age, ultraviolet (UV) light exposure, smoking, medications, and medical conditions.
- Avoiding cataracts causes can keep your vision healthy. But if you develop cataracts, surgery can remove cataracts and help restore vision.
As a person gets older, the lens also ages and can develop a cataract. Cataracts are the most common cause of vision loss, but they’re also treatable. Let’s take a look at what causes cataracts to form, how they affect your vision, and what you can do to lower your risk of developing cataracts.
How do cataracts form?
Cataracts form due to the breakdown of proteins in your lens, which can happen in one or both eyes. This causes the normally clear lens, to become cloudy. This is a normal process that happens as you get older.
Most people develop cataracts after age 40. The older you are, the more likely you are to have cataracts. More than half of people over 80 years old have cataracts.
Cataracts can develop in younger people if they have certain medical conditions. You can also be born with cataracts or develop them in childhood. This can happen because of genetic conditions or from exposure to certain infections like rubella.
What causes cataracts?
Many people wonder how they get cataracts. The answer is simple — they got older. Aging is the main cause of cataracts. As your lens gets older, proteins break down and form a cataract.
But there are other causes of cataracts too. While you can’t stop getting older, there are things you can do to limit and avoid other cataract causes. Here are some other main causes of cataracts.
Medical conditions and genetics
Certain medical conditions and treatments can increase your risk of developing cataracts. These include:
- Diabetes (Types 1 and 2)
- Human immunodeficiency virus (HIV) and/or Acquired immunodeficiency syndrome (AIDS)
- Eye conditions that required surgery (including retinal detachment)
- A history of eye inflammation
- Eye trauma
- Radiation treatment on your upper body
- Having family members with cataracts
Medications
Two major types of medications can increase your risk of cataracts:
- Oral, topical, or intravenous steroids
- Phenothiazines, which treat schizophrenia
Smoking, alcohol, and UV light
People who smoke are more likely to develop cataracts. Studies also show that exposure to sunlight, or ultraviolet (UV) light, can cause cataracts.
How do cataracts affect vision?
Cataracts usually develop gradually, so you may not have trouble with your vision at first. But over time, vision changes start to become more obvious. Common vision changes from cataracts include:
- Blurred vision
- Cloudy vision is like looking through a frosted or dirty window
- A halo or glare around the light
- Impaired night vision
- Faded colours
- Trouble with depth perception
These vision changes can make it hard for you to do your normal activities like reading, working on a computer, or driving — especially at night. If you already wear glasses or contact lenses, you’ll notice that they might not be helping your vision as much anymore.
What are the different types of cataracts?
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There are three types of cataracts:
- Nuclear sclerotic cataracts: This type of cataract forms in the central part of the lens and affects distance vision more than near vision. They grow very slowly.
- Cortical cataracts: These types of cataracts start at the edge of the lens and grow toward the center. They also grow slowly.
- Posterior subcapsular cataracts: This type of cataracts forms in the back of the lens. They tend to grow faster and cause severe glare in bright sunlight or from vehicle headlights.
How do you know if you have cataracts?
An eye exam is the best way to figure out if you have cataracts.
You can’t see cataracts by looking in the mirror. But you may notice vision changes as cataracts start to mature. People often experience vision changes like:
- Trouble focusing when going from looking at things closely to far away
- Trouble seeing in low light
- Glare sensitivity
You may also notice that colours seem faded and less bright. Other people notice that their prescription lenses no longer work as well as they used to.
See an optometrist or ophthalmologist if you experience any of these vision changes. They can perform a dilated eye exam which is the best way to know if you have cataracts.
What should you do if you’re experiencing symptoms of cataracts?
If you’re having trouble with your vision, you should see an eye doctor and have an eye exam.
Your eye doctor will offer you glasses or contact lenses to help with your vision if you have cataracts. They may also suggest that you use brighter lighting in your home to help you see or recommend an anti-glare coating for your glasses.
If you have cataracts, your eye doctor will ask you to come back once or twice a year for checkups. If your glasses or contact lenses are no longer helping your vision, they might also suggest that you have surgery to remove your cataracts.
How can you protect your vision as you age?
Even though cataracts are a normal part of ageing, there are still things that you can do to protect your vision. Avoiding causes of cataracts can delay their development as you get older. Here are some things you can do to protect your eyes:
- Stop smoking: Smoking cigarettes increases your risk of developing cataracts, so it’s best to quit smoking to protect your eye health.
- Protect your eyes from UV light: Wear sunglasses with UV light protection or a wide-brimmed hat when you’re outside.
- Eat a diet rich in leafy green vegetables: There’s some evidence that people who eat a diet high in leafy greens have fewer cataracts.
The bottom line
Cataracts are a common cause of decreased vision, and they affect each person differently. You’re more likely to develop cataracts as you get older. Getting new glasses with anti-glare coating and using brighter lighting may help treat your cataract symptoms. Avoid smoking, and protect your eyes from sunlight to keep your vision healthy.
