Cataracts: Causes and Natural Prevention
Worldwide, cataracts are the second leading cause of visual impairment, after refractive errors (nearsightedness, farsightedness, astigmatism, etc.). They’re extremely common, affecting half of all Americans by the time they reach age 80. But common doesn’t mean inevitable. There are many things you can do to prevent cataracts from forming. But before getting into that, it’s helpful to understand what cataracts are and why they develop in the first place.
What Is a Cataract?
A cataract is the clouding of the lens in the eye. The lens is the clear part of your eye that helps to focus an image on the retina, the tissue at the back of your eye.
Normally, light passes through the lens to the retina, where it is transformed to signals that are sent to the brain. When the lens is transparent, the retina receives a sharp image, but if it is clouded over (as is the case with cataracts), the image is blurred.
The lens is made of water and protein, which is arranged in such a way that the lens remains clear. Over time, some of the proteins may begin to clump together, which clouds up areas of the lens. Thus, a cataract is born. Cataracts usually start small but tend to grow larger.
There are three types, named according to where they first form.
- Nuclear cataracts grow in the nucleus (center) of the lens. These are the most common type.
- Cortical cataracts grow in the outer areas of the lens, called the cortex.
- Posterior subscapsular cataracts form in the back, in the capsule that surrounds the lens. These occur mostly in people with diabetes or obesity.
Advancing age is the biggest risk factor, but lifestyle also plays a role. For instance, those who smoke or have diabetes are at higher risk. Cumulative exposure to ultraviolet (UV) light from the sun can also contribute to cataracts.
Along with cloudy or blurred vision, other symptoms of cataracts include halos around lights, double vision, colors appearing faded, and poor night vision. If you experience any of these symptoms, it’s time to see an eye doctor.
The symptoms of early cataracts can be improved with special glasses, sunglasses, or magnifying lenses, but the only real “cure” is surgery, which entails removing the cloudy lens and replacing it with a clear artificial lens. Cataract surgery is one of the most common—and also safest and most effective—operations performed in the US. Over 90% of people end up with better vision afterward.
Even though cataract surgery has a longstanding history of safety, all surgery has risk. Benefits and risks should be weighed appropriately before jumping into this procedure—but odds are, you’ll come out on the other end just fine, and ecstatic with your newfound vision.
While cataracts are by no means life threatening, prevention is always preferable to treating a condition after it’s developed. Fortunately, cataracts are very preventable. While you can’t turn back the hands of time, these lifestyle habits go a long way in protecting the eyes:
- Wear polarized sunglasses that block 100% UV light. Since UV exposure is one of the biggest risk factors for cataracts, sunglasses should be a no-brainer. Wear them all the time, even on cloudy or overcast days. One study recommends choosing sunglasses that “block wavelengths below 400 nm (marked 400 on the glasses). However, because of the geometry of the eye, these glasses must be wraparound sunglasses to prevent reflective UV radiation from reaching the eye.”1
- Check your meds. Certain drugs have been shown to increase the risk of cataract formation because they make your eyes more sensitive to UV light. There are too many of these drugs to list here, but some of the top culprits include nonsteroidal anti-inflammatory drugs (NSAIDs); certain antibiotics and antiarrhythmics; statins; diuretics; antihistamines; antifungals; and sulfonylureas. If you take any of these medications on a regular basis, discuss possible alternatives with your doctor, and be sure to wear sunglasses (and even a wide-brimmed hat for extra protection) when outside.
- Quit smoking. Smokers are three times more likely to get cataracts than nonsmokers.2
Nutrients for Your Eyes
Along with lifestyle, diet plays a huge role in the health of your eyes and the prevention of cataracts.
Antioxidants are especially important because they neutralize damaging free radicals that speed up the aging process in your eyes (and everywhere else). When it comes powerful antioxidants for the eyes, there’s no greater superstar duo than lutein and zeaxanthin.
These two carotenoids have been well studied for the prevention of several eye disorders, including age-related macular degeneration and cataracts.
In one early study that followed 1,354 adults, researchers determined that those who had the highest intake of lutein and zeaxanthin were half as likely to get cataracts, compared to those with the lowest intake.3
More recent research confirms these benefits. A 2014 meta-analysis of six studies involving 41,999 participants found a significant risk reduction in nuclear cataracts. The higher the intake, the greater the benefit. The researchers wrote, “Dietary lutein and zeaxanthin intake is associated with a reduced risk of age-related cataracts (ARC), especially nuclear cataract in a dose-response manner, indicating a beneficial effect of lutein and zeaxanthin in ARC prevention.”4
An even more recent meta-analysis published in 2019 looked at a total of 20 studies. It found that most carotenoids/antioxidants, including vitamin C, beta-carotene, lutein, and zeaxanthin, were significantly associated with reduced risk of cataracts. Further analysis showed that risk decreased by a whopping 26 percent for each 10 mg/day increase in lutein or zeaxanthin intake! (Vitamin C came in at an impressive second place, reducing risk by 18 percent for each 500 mg/day increase).5
Both lutein and zeaxanthin are readily available as standalone or combination products. Many multivitamins also contain these important carotenoids. Take a minimum of 10 mg lutein and 2 mg zeaxanthin per day. For greater therapeutic effects, you can double, triple, or even quadruple these dosages.
Other antioxidants that nourish and protect the eyes include zinc, beta-carotene, vitamins A, C, and E, and glutathione. In fact, glutathione is found in high concentrations in the eyes’ lenses, where it maintains their transparency.6 So, deficiency in glutathione can contribute to lens clouding. The easiest way to boost your glutathione stores is to take its precursor, N-acetyl-cysteine, in supplement form.
Another antioxidant, carnosine, is also proving to be helpful not only preventing but also halting the advancement of cataracts. Carnosine works by hampering a process known as glycation, where proteins and sugar molecules bind together and form disease-causing compounds called advanced glycation end-products (AGEs). AGEs are an underlying cause of countless age-related diseases, including cataracts and macular degeneration. Carnosine, however, occupies the binding sites where sugars normally land, thus decreasing the formation of AGEs. The most effective way to deliver carnosine to the eyes is with drops, which can be purchased online.
Finally, be sure to schedule a comprehensive eye exam regularly. Your eye doctor can tell you how often you need to be seen based on your eye and overall health. For most people, every two years should suffice, but people with existing eye diseases or diabetes need to be seen more often. As with any health concern, the sooner you detect a cataract, the quicker you can take action to slow its progression and lower your chances of needing surgery in the near future.
- Roberts JE. Ultraviolet radiation as a risk factor for cataract and macular degeneration. Eye Contact Lens. 2011 Jul;37(4):246-9. Last accessed May 29, 2019.
- Kelly SP, et al. Smoking and cataract: review of causal association. J Cataract Refract Surg. 2005 Dec;31(12):2395-404. Last accessed May 30, 2019.
- Lyle BJ, et al. Antioxidant intake and risk of incident age-related nuclear cataracts in the Beaver Dam Eye Study. Am J Epidemiol. 1999 May 1;149(9):801-9. Last accessed May 30, 2019.
- Ma L, et al. A dose-response meta-analysis of dietary lutein and zeaxanthin intake in relation to risk of age-related cataract. Graefes Arch Clin Exp Ophthalmol. 2014 Jan;252(1):63-70. Last accessed May 30, 2019.
- Jiang H, et al Dietary vitamin and carotenoid intake and risk of age-related cataract. Am J Clin Nutr. 2019 Jan 1;109(1):43-54. Last accessed May 30, 2019.
- Giblin FJ. Glutathione: a vital lens antioxidant. J Ocul Pharmacol Ther. 2000 Apr;16(2):121-35. Last accessed May 30, 2019.
- Natural Medicine Journal. https://www.naturalmedicinejournal.com/journal/2010-04/l-carnosines-effects-cataract-development. Last accessed May 30, 2019.