What Causes Cataracts? Signs, Symptoms & Treatment

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One of the most common age-related vision problems is cataract—a clouding of the lens, the normally transparent structure located in the front of the eye that transmits and focuses light onto the retina.

According to the National Eye Institute, by age 80, 70% of white Americans, 61% of Hispanic Americans, and 53% of African Americans have or have been treated for cataracts. They’re so common in the 70-plus bunch that many consider them a normal part of aging.

Why Are Cataracts So Common?

To understand why cataracts are so common, you need to know a little bit about the lens.

Each of your eyes contains a lens, made up of cells that are comprised of precisely aligned, elongated, transparent crystallin proteins. Unlike most other cells in your body, lens cells have no internal structures like nuclei or mitochondria and no blood supply. Instead, they are nourished passively by the diffusion of nutrients from the aqueous humor (the fluid in the front of the eye).

These unusual features give the lens its transparency and clarity—but also limit its capacity for repair and regeneration.

To give you a comparison, cells in your intestinal tract are renewed and replaced every four to five days. Red blood cells live for about four months. The cells of your eye lenses, on the other hand, last a lifetime.

When you consider these unique characteristics, it’s no surprise that time takes a toll on the lens.

What Causes Cataracts?

The primary cause of age-related cataracts is the accumulation of years of damage to the lens from two major sources.

The first is oxidative stress, which occurs when your body’s antioxidant defenses cannot keep up with the production of free radicals. Your eyes are exposed to a tremendous amount of light, including ultraviolet (UV) radiation and other potentially harmful wavelengths of light. UV radiation is a well-known cause of oxidative stress.

The other is glycation. Glycation is a reaction in which sugar molecules attach to proteins or lipids, triggering the formation of advanced glycation end products (AGEs). AGEs are marked by crosslinking or bonding of proteins, which not only impairs their function but also ramps up oxidative stress. This causes proteins in the lens to break down and gradually form dense, cloudy clumps—making the lens less transparent with a yellowish hue.

What Are the Symptoms of Cataracts?

Cataracts actually begin developing around age 40 but progress so slowly they go unnoticed for decades.

Only when a cataract gets to the point that it significantly interferes with light transmission to the retina do vision changes become evident. Cataract signs and symptoms, which may affect one or both eyes, include:

  • Blurry or hazy vision
  • Faded colors
  • Worsening night vision
  • Halos around lights at night
  • Glare sensitivity
  • Requirement for brighter light indoors
  • More frequent changes in eyeglass prescriptions
  • Double vision

Additional Causes of Cataracts

Although most cataracts are related to decades of oxidative and glycation-induced damage, other factors besides aging also increase your risk:

  • Diabetes doubles the risk of cataracts and dramatically increases the likelihood of developing them at a younger age. Elevated blood sugar ramps up glycation and the production of AGEs, which play a central role in most diabetic complications.
  • Congenital cataracts, present at birth or during childhood, may be genetic or related to a maternal infection during pregnancy.
  • Cancer treatments including radiation, hormone therapy, and chemo can cause cataracts and other eye problems.
  • Steroids such as prednisone, used in high doses for prolonged periods, increases the likelihood of developing posterior subcapsular cataracts, a type that forms relatively rapidly in the back of the lens.
  • Statins and cataracts have been linked in several studies, including a 2019 meta-analysis of 21 studies showing that statin use increased risk.
  • Shingles can cause cataracts, glaucoma, and other vision disorders when it affects the nerves of the eye (herpes zoster ophthalmicus).
  • Lifestyle factors that increase the risk of cataracts include smoking, heavy drinking, obesity, poor diet, chronic dehydration, and excessive exposure to radiation and UV light.

Fortunately, Cataracts Are Treatable

If cataracts impair your vision enough to interfere with your usual activities, you should definitely consider surgery. Cataract surgery is a quick outpatient procedure that involves replacing a clouded lens with a plastic one. Performed millions of times a year, it is quite safe, and most people end up with better vision.

Yet, surgery isn’t always necessary. There are several natural remedies for cataracts that not only reduce risk and slow progression but also help guard against other vision problems.

  • New glasses: Vision impairment related to cataracts can often be improved with a new eyeglass prescription. Surgery can be delayed and, in some cases, avoided altogether.
  • Good diet & optimal weight: The long-running Blue Mountains Eye Study found that a healthy diet plus optimal weight were associated with a reduced risk of cataracts. Specific foods I recommend for eye health include fruits and vegetables (especially dark leafy greens), omega-3-rich fish, olive oil, and other whole foods. Avoid sugars and excess carbohydrates, and go easy on grilled, fried, and roasted foods. Harmful AGEs are formed when proteins and fats are cooked at high temperatures, and dietary AGEs are detrimental to overall health.
  • Healthy lifestyle: Exercise, stay well-hydrated, don’t smoke, avoid excess alcohol, and wear sunglasses.
  • Multivitamins: The role of vitamins for cataract prevention has been examined in multiple studies. Harvard researchers reported that men who took a daily multivitamin had a lower risk of cataracts. Look for a supplement with high levels of protective antioxidants, including zinc and vitamins A, C, and E. The association between vitamin C and cataracts is particularly robust. I suggest taking a minimum of 1,000 mg of vitamin C per day.
  • Lutein & zeaxanthin: I also recommend a vision-targeted supplement with therapeutic levels of lutein 20–40 mg and zeaxanthin 2–4 mg. Several studies have linked a high lutein intake or blood level with reduced odds of developing cataracts.
  • N-acetyl-carnosine eye drops: Carnosine is an amino acid derivative that inhibits the formations of AGEs. A handful of small studies show that when carnosine eye drops were applied twice a day, improvements were noted in vision and lens opacity. Although further research is needed, some of my patients have reported benefits with this therapy.

Can Cataracts Be Reversed?

You may be wondering if these suggestions will help if you already have cataracts. Your ophthalmologist will likely say no, but my clinical experience says otherwise. I’ll close with a story about a patient I saw several years ago.

Mary’s vision had been slowly declining for years. Lights seemed to have halos around them, and she was more sensitive to glare and less comfortable driving at night. Colors were duller, and she needed brighter light to read. She finally saw an eye doctor, who told her she had cataracts and needed surgery in both eyes.

She had cataract surgery on her left eye with a good outcome and scheduled surgery on the right eye. Meanwhile, she started taking a high-potency vision supplement in addition to her daily multivitamin. Within months, the improvements in her right eye were so noticeable that she opted out of surgery—and her ophthalmologist agreed. Two years later, she was still taking her supplements and her vision was holding steady.

Dr. Julian Whitaker

Meet Dr. Julian Whitaker

For more than 30 years, Dr. Julian Whitaker has helped people regain their health with a combination of therapeutic lifestyle changes, targeted nutritional support, and other cutting-edge natural therapies. He is widely known for treating diabetes, but also routinely treats heart disease and other degenerative diseases.

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