Night Blindness Vitamin Deficiency

Night blindness is characterized by defective vision in reduced light

. It may result from a genetic disease, intake of certain drugs or a deficiency of vitamin A. Night vision blindness can vary in intensity. In some cases it may be mild, while in other cases it can be severe. It can also hamper daily functioning in certain occupations such as the military.

The retina of the eye allows us to see. The retina is composed of a network of nerve cells which enable an individual to see. There are two kinds of cells, rods and cones. Cones work well in bright light and are involved in color vision. Rods work when there is less light, but cannot see color. The cones are located mostly in the center of the retina and the rods are present around the edges. When there is complete darkness, both the cones and rods cannot function and hence we are not able to see anything. But in dim light, we are able to see properly due to the rods. Night vision blindness results from impairment in functioning of the rods. The main cause of this condition is usually a defect in the retina. Many medical conditions can result in problems in the retina. One of the most common night blindness causes is cataracts. Cataracts are characterized by cloudy areas in the eye lens. It usually occurs in older individuals. Night blindness in younger individuals may be indicative of a condition called retinitis pigmentosa, which causes damage to the retina. Those with myopia may also suffer from night blindness. The individual may find it difficult to focus his eyes and therefore far objects may seem blurry. The individual may also have trouble in adapting to darkness. Another cause of night vision blindness is vitamin A deficiency. This vitamin helps to maintain the health of the eyes and skin. Night blindness symptoms include blurred vision, dryness of the eyes and an inability to differentiate images in dim light.

Night blindness treatment involves consuming foods that are rich in Vitamin A. This vitamin is present in foods such as animal liver and whole milk. Vegetables such as pumpkin, carrots, cantaloupe and fruits such as papaya and mangoes are also rich in vitamin A. Other valuable sources of this nutrient are butter and egg yolk. Supplements of vitamin A are also widely available. Vitamin A in high doses may also help to delay the progression of night blindness caused by genetic factors.

by: Kevin Pederson

POST COMMENT

Go Cart Chassis - How To Choose The Best One About Work Away Days Understanding Vitamin E Make Mine Southern! England Fight Against Scotland In Rugby World Cup 2011 Leadanswer.com: Comprehensive Leads Is The Key Of Success A Simple Way To Make A Cake What You Should Know About Meta Tags Grilled Shrimp Recipe Mister Wong - A Guide For Social Bookmarking How To Begin Personal Growth Process Save Your Precious Time with Hand Blenders Maternity Must-Haves For The Office