Over 3 million Americans over 40 suffer from some sort of visual impairment. Vision loss is one of the major causes of disabilities, and age-related eye diseases (AREDs) are rapidly becoming a public health problem in developed countries. Visual impairment caused by AREDs can lead to other serious health issues including decreased mobility, depression, hip fractures, other accidents, and an overall lower quality of life. Most AREDs do not have effective treatments and it is therefore important to maintain eye health and prevent vision deterioration.
Cataracts, glaucoma, age-related macular degeneration and diabetic retinopathy constitute the majority of AREDs. Cataracts are responsible for 51% of world blindness. With cataracts, vision loss is caused by an increasing opacity of the lens of the eye. It is one of the easiest AREDs to treat as surgical cataract removal can successfully restore vision. Glaucoma is a group of diseases characterized by optic nerve damage. It is referred to as the “Silent Thief of Sight” due to a lack of specific symptoms delaying the diagnosis, with many patients requiring life-long medications. Age-related macular degeneration (AMD) causes loss of the central field of vision due to reduced blood flow to the macula, a specialized part of the retina. It is the leading cause of blindness in developed countries. Currently, there is no cure for AMD and it can only be managed by supportive assistance. Diabetic retinopathy, a complication of long-standing diabetes, is caused by leakage from the retinal blood vessels leading to vision loss. By maintaining blood sugar levels within normal limits it is one of the easily preventable visual diseases.
Integration of the eyes with the brain and other parts of the body requires thousands of communication channels constituting many types of cells to function together as a visual system. The main structures of this system are the retina, sclera, pupil, iris, cornea, lens, macula, aqueous and vitreous humor, optic disk, and optic nerve. Specific nutrients are required for proper functioning and communication within various components of this system. For example, the retina is composed of hundreds of thousands of small rods and cones that sense light and are responsible for color vision. Nutrients such as lutein, zeaxanthin, cryptoxanthin, beta carotene, zinc, bioflavonoids, and vitamins A and C are essential for the proper functioning of these cells in the retina and macula. The ciliary muscles in the eye help in contraction and relaxation of the lens to adjust and focus on a particular object. The optic nerve carrying signals and light impulses from the retina to the brain consists of approximately 1 million nerve cells. Natural nutrients such as the amino acid cysteine, vitamins C and E, and lipoic acid all work in synergy to protect physical functions of the optic nerve. The blood vessels that supply blood and nourishment to the eyes are made of cells that require the amino acid arginine for contraction and relaxation, and vitamin C to ensure optimum collagen production to support blood vessel strength and integrity. Vitamin C is known to reduce ocular pressure in the eyes, however the content of vitamin C in the eyes naturally decreases with age and requires additional supplementation.
Age-related circulatory diseases such as diabetes, hypertension, strokes, free radical damage caused by ultraviolet light, smoking, and other toxic chemicals are the most common risk factors for the majority of AREDs. Moreover, environmental pollutants and medications such as steroids, antidepressants, and oral contraceptives contribute to nutrient depletion and AREDs. Additionally, exposure to artificial light, computers, TVs and other screens is becoming the main contributor to significant eyestrain in the younger population, leading to early development of visual problems. While we cannot stop aging, we can prevent its negative effects on our eyes. A healthy lifestyle, including avoidance of damaging risk factors and appropriate cellular nutrients to support eye health, will help maintain optimum vision.