Recent years have seen a surge in the use of nutrients and supplements to not only help manage age-related vision complications, but also enhance night vision, visual acuity, light flicker sensitivity, and vision performance as a whole. This glossary details key terms and concepts within the realm of vision enhancement and supplementation.
The process in which eyes focus in order to maintain a clear image. It can be either be consciously or reflexively performed. The vision enhancer astaxanthin is said to help improve visual accommodation in people with blurry vision.
Chemical compounds drawn from plants that carry an electric charge, which imbues fruits and flowers with their deep blue, purple, orange, and red hues. They have been shown to improve eye health, especially by reducing inflammation in the retina. Bilberries are chock-full of anthocyanins. C3G may be the most potent vision-enhancing anthocyanin.
Naturally-occurring compounds present in many everyday fruits, vegetables, and other plants that help reduce damage to cells – including those present in the eyes – caused by reactive oxygen species. Many supplements incorporate antioxidants in order to minimize the negative health consequences of oxidative stress, which is believed to be implicated in a wide range of health disorders.
Also known as eye plaques, Bitot’s spots are small deposits of keratin on the mucous membrane lining the front of the eye and the inside of eyelids. Vitamin A deficiency is one of its main causes.
A group of over 750 pigments that are naturally produced by plants, algae, and bacteria, and serve as the sources of the yellow, orange, and red colors of many fruits and vegetables. They may have several vision-enhancing benefits: protecting eyes from oxidative stress, being a source of vitamin A, and filtering blue light. The most common carotenoids in U.S. diets are alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, lycopene, and zeaxanthin.
A condition in which vision becomes “cloudy” as a result of proteins clumping together in the lens of the eye. It is the most common reason for vision loss in people over 40 years of age as well as the leading cause of blindness. Various vision enhancers are given to reduce the risk of cataracts.
A measure of visual function, contrast sensitivity refers to ability to visually distinguish between objects and their background, especially when there is glare or low light. Zinc supplements may help improve contrast sensitivity.
Dark adaptation is the eye’s gradual increase in light sensitivity under reduced illumination. The cones of the eye’s retina are responsible for rapid adjustment to dark conditions, whereas the rods are in charge of long term dark adaptation. Bilberry is ideal for managing dark adaptation
Diabetic retinopathy refers to the swelling, leaking, or abnormal growth of blood vessels on the retina. It is the most common diabetic eye condition and a major cause of blindness in the U.S.
Dry Eye Syndrome
Also known as xerophthalmia, dry eye syndrome is a chronic lack of eye lubrication and moisture that may lead to itching, burning, redness, and tearing of the eye. Computer users, females, and adults over the age of 40 years are most susceptible. The visual fatigue, blurry vision, and discomfort it causes can significantly hinder day-to-day life.
Eye diseases characterized by damage to the optic nerve and subsequent vision loss are collectively called glaucoma. Chief risk factors for glaucoma include a family history of the condition, increased eye pressure, high blood pressure, and obesity. Progression of glaucoma can be slowed or even stopped with medication or surgery.
Light Flicker Sensitivity
The eye’s reaction to flashing or flickering lights. On average, the human eye is able to withstand up to 50 flashes per second. Excessive exposure to flickering lights and patterns may trigger seizures. The vision enhancer saffron is often used to help improve light flicker sensitivity.
An eye condition in which central vision is blurred or gone. It generally develops over time due to damage to the center of the retina – the macula – and is one of the leading causes of vision loss in adults in the U.S.
Night blindness is the inability to see well in the darkness. It is a symptom of various eye conditions related to the degeneration of retinal rods.
Photoreceptors are specialized cells in the retina that are able to convert light into electrical signals. The three types of photoreceptors are rods (primarily used for night vision), cones (mainly used for day vision), and ganglion cells (used to manage circadian rhythms).
Phytochemicals are chemicals produced by plants that have potential health benefits. Some phytochemicals have vision-enhancing properties.
The retina is the inner layer of the eye responsible for converting light rays into signals that the are interpreted as images by the brain. Astaxanthin is said to help preserve the well-being of the retina.
Frequently called “visual purple,” rhodopsin is a light-sensitive receptor protein found in the rods of the retina known for aiding vision in low-light conditions via its acute light sensitivity. Black currant may enhance rhodopsin regeneration.
Simply referred to as light, the visible spectrum is the part of the entire electromagnetic spectrum that the human eye is able to detect. The average eye responds to wavelengths from 390 to 700 nanometers, which in colors ranges from violet to red.
Visual acuity is clarity of vision, which basically means how well a person is able to see. Its three principal factors are the eye’s ability to focus, the retina’s health, and the brain’s capacity to interpret signals from the eye.