Vitamin E (tocopherol) is a powerful antioxidant which protects cell membranes and other fat-soluble parts of the body. Studies suggest that supplementing with Vitamin E helps to prevent heart disease. Vitamin E is a fat-soluble vitamin present in many foods, especially certain fats and oils. It is one of a number of nutrients called antioxidants. Alpha-tocopherol is the most active
form of vitamin E in humans, and is a powerful biological antioxidant. Vitamin E deficiencyin humans results in ataxia (poor muscle coordination with shaky movements), decreased sensation to vibration, lack of reflexes, and paralysis of eye muscles. One particularly severe symptom of vitamin E deficiency is the inability to walk.
Vitamin E deficiency is rare in humans. When it does occur, it is typically in one of three situations: among very low birth-weight premature infants, in individuals who lack the ability to absorb dietary fat, and among those affected by certain rare disorders of fat metabolism. There are three specific situations when a vitamin E deficiency is likely to occur. It is seen in persons who cannot absorb dietary fat, has been found in premature, very low birth weight infants (birth weights less than 1500 grams, or 3 1/2 pounds) and is seen in individuals with rare disorders of fat metabolism. Infants are born in a state of relative vitamin E deficiency. Vitamin E deficiency in premature infants persists during the first few weeks of life and can be attributed to limited placental transfer of vitamin E, low tissue levels at birth, relative dietary deficiency in infancy, intestinal malabsorption, and rapid growth.
Vitamin E deficiency affects the central nervous system and may result in progressive neuromuscular disease characterized by loss of reflexes, muscle weakness, loss of balance and impaired ability to coordinate voluntary movements (ataxia). Vitamin E deficiency can be seen in people unable to absorb fat properly. Such conditions include pancreatitis (inflammation of the pancreas), cystic fibrosis, and biliary diseases (illnesses of the gallbladder and biliary ducts). Symptoms of deficiency include muscle weakness, loss of muscle mass, abnormal eye movements, impaired vision, and unsteady gait. Eventually, kidney and liver function may be compromised. In addition, severe vitamin E deficiency can be associated with serial miscarriages and premature delivery in pregnant women. Severe vitamin E deficiency results mainly in neurological symptoms, including impaired balance and coordination (ataxia), injury to the sensory nerves (peripheral neuropathy), muscle weakness (myopathy), and damage to the retina of the eye (pigmented retinopathy).
Vitamin E deficiency strikes people with diseases that prevent the absorption of dietary fats and fat-soluble nutrients. These diseases include cystic fibrosis, pancreatitis, and cholestasis (bile-flow obstruction). Bile salts, produced in the liver, are required for the absorption of fats. Cholestasis causes a decrease in the formation of bile salts and the consequent failure of the body to absorb dietary fats. For this reason, this disease may result in vitamin E deficiency. Premature infants may be at risk for vitamin E deficiency because they may be born with low tissue levels of the vitamin, and because they have a poorly developed capacity for absorbing dietary fats. Infants suffering from fat-malabsorption diseases can develop symptoms of vitamin E deficiency by age two. In adults, the onset of a fat-malabsorption disease can provoke vitamin E deficiency after a longer period, as an example, ten years.
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