Why Does Vitamin A Deficiency Cause Night Blindness
Wolbach and howe 1925.
Why does vitamin a deficiency cause night blindness. Anemia and poor skin and hair health are also common as are frequent infections. Other causes of vitamin a deficiency are inadequate intake fat malabsorption or liver disorders. Blood testing can measure your vitamin a and glucose levels.
Vitamin a deficiency also harms the immune system the body s ability to fight disease. As with any medication or supplement excessive doses or unnecessary exposure can be harmful. For humans the most well known effects of vitamin a deficiency are night blindness dowling 1966 and childhood mortality and morbidity sommer 1997a.
Therefore doses above the ul should be avoided because vitamin a has been associated with an increase risk for hip fracture in postmenopausal women lung cancer cardiovascular mortality and total mortality. Less vitamin a means synthesis of rhodopsin isstunted which affects our ability to see and distinguish light anddark. Periodic high dose vitamin a supplementation is a proven low cost intervention 1 which has been shown to reduce all cause mortality by 12 to 24 per cent 2 and is therefore an important programme in support of efforts to reduce.
Acute vitamin a deficiency results in night blindness. This increases the chance of death from malaria measles and diarrhea. Deficiency impairs immunity and hematopoiesis and causes rashes and typical ocular effects e g xerophthalmia night blindness.
Vitamin a deficiency is the leading cause of preventable childhood blindness and increases the risk of death from common childhood illnesses such as diarrhoea. Night blindness caused by nearsightedness cataracts or vitamin a deficiency is treatable. Vitamin a deficiency affects a wide range of organ systems in vertebrates west 1994.
Eye problems are related to vitamin a deficiency. Too little vitamin a can lead to inflamed skin night blindness infertility delayed growth and respiratory infections. Corrective lenses such as eyeglasses or.
The inability to produce tears is the first sign of vitamin a deficiency. A vitamin a deficiency vad is usually triggered by poor nutrition or health problems that interfere with its absorption. Vad can cause eye diseases such as night blindness bitot s spots corneal xerosis or ulcers and keratomalacia.
Without vitamin a night blindness occurs.
