Cataract: the most effective dietary supplements

Cataract is a common eye condition characterized by the progressive clouding of the lens, a biconvex structure inside the eye that focuses images onto the retina. This disorder leads to a gradual loss of lens transparency and, without treatment, can result in blindness. Cataract is the leading cause of reversible blindness worldwide.

Epidemiology

The prevalence of cataract increases with age. Nearly 10% of people aged 50 to 59 show signs of lens clouding, a figure that rises to 81% in those over 80. In 2015, cataract was responsible for 51% of global blindness cases, affecting about 12.6 million people. It is more common in women than in men, and its incidence is exacerbated by factors such as UV exposure, smoking, and certain metabolic diseases like diabetes.

Pathophysiology

The lens is composed mainly of water and proteins, whose transparency is essential for its function. Cataract occurs when this balance is disturbed, causing protein aggregation and loss of transparency. Several mechanisms underlie cataract formation: • Protein oxidation: Oxidative stress is one of the key factors in cataract formation. The lens contains high levels of reduced glutathione, a powerful antioxidant molecule. When glutathione levels fall, lens proteins oxidize, lose their transparency and become insoluble. • Electrolyte disturbances: An osmotic imbalance within the lens, notably elevated calcium, can lead to alteration of the cell membrane and the lens structure. • Advanced glycation end products (AGEs): These compounds, formed by the binding of sugars to proteins, accelerate the degradation of lens proteins, contributing to cataract formation, particularly in diabetic patients.

Risk Factors

Several factors increase the risk of developing cataract: • Age: This is the main factor, with a significant increase in cases after age 50. • UV exposure: Prolonged, unprotected exposure to sunlight contributes to lens clouding. • Smoking and alcohol: Both are associated with increased oxidative stress, accelerating lens aging. • Metabolic diseases: Diabetes, due to high blood glucose levels, promotes glycation of lens proteins. • Corticosteroids: Prolonged use of these medications is also linked to an increased risk of cataract.

Symptoms

Cataract presents with several symptoms, including: • Gradual decrease in visual acuity: Vision becomes blurry or hazy, often described as if objects are seen through a fogged window. • Photophobia: Increased sensitivity to light, especially outdoors or under bright lights. • Glare: Night vision is disturbed, with halos around light sources. • Altered color perception: Colors appear faded, particularly blue tones which become harder to distinguish. • Monocular diplopia: Double vision may occur in the eye affected by the cataract.

Diagnosis

The diagnosis of cataract is mainly based on clinical examinations, with measurement of visual acuity being a central element. This assessment quantifies vision loss and identifies the specific effects of cataract on the patient’s visual function. Another fundamental test is examination of the lens after pupil dilation using ophthalmic drops. This exam allows the doctor to observe the lens opacification and assess its location and extent. Several forms of cataract are distinguished by their location in the lens, such as nuclear, cortical, or posterior subcapsular cataract. Each type has specific characteristics that influence how vision is affected. Nuclear cataract, for example, tends to cause blurred distance vision, while cortical cataract is often associated with glare, especially in the presence of bright lights.

Treatment

The only effective treatment for cataract is surgical. The standard procedure involves removing the clouded lens and replacing it with an artificial intraocular lens. This operation, called phacoemulsification, has become a routine surgery, performed under local anesthesia with a very high success rate. After the procedure, visual recovery is generally rapid and patients can resume normal activities within days. In some cases, vision correction with glasses or contact lenses remains necessary, but most patients regain an excellent quality of life.

Prognosis and Prevention

The prognosis after cataract surgery is generally excellent, with significant restoration of vision for the majority of patients. Phacoemulsification provides quick and lasting results. Visual recovery begins within the first hours after surgery, and most patients regain functional vision within days. However, without treatment, cataract progresses slowly and can lead to total blindness, particularly in older individuals. To prevent cataract development, it is essential to minimize exposure to major risk factors. One of the most effective preventive measures is protecting the eyes from ultraviolet rays by wearing UV-filtering sunglasses. Quitting smoking and moderating alcohol consumption are also important recommendations, as these habits increase oxidative stress, a factor in lens clouding. Nutritionally, a diet rich in antioxidants, particularly vitamins C and E, plays a protective role by limiting damage caused by free radicals to the lens. Finally, for people with diabetes, strict blood sugar control is essential, as poor management accelerates cataract development.