Vitamin E Deficency and Toxicity

Deficiency

Causes
 
Deficiency in vitamin E is rare, particularly in healthy people. However, one group in which it has been documented is infants, particularly if born prematurely, who have been fed formulas containing inadequate amounts of vitamin E. During the 1960s and 1970s, some infant formulas contained high levels of polyunsaturated fatty acids (PUFAS), but low levels of vitamin E.  Since PUFAs are very susceptible to damage from the oxidation of free radicals, the need for vitamin E in the babies given these formulas was increased, while in fact, they were getting much less vitamin E than they needed. The resulting outbreak of hemolytic anemia, especially in babies who were born prematurely, led to mandating vitamin E fortification of infant formulas.
 
Other conditions that put an individual at high risk for a vitamin E deficiency are genetic defects affecting lipoproteins or alpha-tocopherol transfer proteins and any disorder involving fat malabsorption (since vitamin E is a fat-soluble vitamin). Thus, pancreatic insufficiency, celiac disease, and gallbladder disease are some of the conditions that might induce a vitamin E deficiency. Vitamin E deficiency is also found in individuals with other serious gastrointestinal disorders such as short bowel syndrome, chronic cholestasis (decreased bile production), chronic steatorrhea (excess fat in the feces), and cystic fibrosis (which not only affects the lungs, but also the pancreas, liver, kidneys, and intestines). People receiving total parenteral nutrition without adequate vitamin E are at high risk as well.

Symptoms

Vitamin E deficiency can be difficult to diagnose because there is no clearly defined deficiency disease in human beings like beriberi for thiamin or rickets and osteomalacia for vitamin D. Not only can the symptoms vary greatly since so many different parts of the body (e.g., the nervous system and muscular, circulatory, and respiratory systems) can be affected, many of the symptoms can have other causes. Furthermore, some symptoms of vitamin E deficiency can take as long as 5-10 years to develop. Vitamin E deficiency can be diagnosed by measuring measure vitamin E (tocopherol) blood levels or by the RBC fragility test. In addition, excess creatinine in the urine would indicate muscle breakdown consistent with a vitamin E deficiency. The following are the important symptoms frequently associated with vitamin E deficiency in infants, children, and adults.
 
Premature infants and children:  
  • Irritability
  • Edema
  • Hemolytic anemia
Adults:  
  • Listlessness and fatigue
  • Apathy
  • Difficulty concentrating
  • Neuromuscular abnormalities: muscle pain and weakness, loss of muscle coordination
  • Peripheral neuropathy: pain, tingling, and lack of sensation in the extremities
  • Skeletal myopathy
  • Ataxia: loss of voluntary coordination of body movements
  • Retinopathy
  • Hemolytic anemia
One of the first symptoms of vitamin E deficiency is the loss of red blood cells due to cells becoming more fragile as membranes become less protective. Oxidized polyunsaturated fatty acids may also contribute to the weakening of the cell membranes.
 
As the cells and tissues become more susceptible to the damage of oxidized free radicals, additional symptoms occur such as abnormal fat deposits in muscles, muscle wasting, and kidney and liver dysfunction and, in men, changes in the testes. Pituitary and adrenal gland function may be impaired as well.

People Who May Benefit from Additional Amounts of Vitamin E

Although vitamin E supplements are widely touted and have become very popular, not everyone who takes them probably needs them. The amount of vitamin E that an individual requires depends on age, body size, amount of polyunsaturated fats and fried foods included in the diet, and whether there is already a deficiency or other condition that increases the risk of developing a deficiency. The guidelines set by the Institute of Medicine are intended to apply to most people, but there are exceptions. The following are some of the people who might benefit from additional amounts of vitamin E.  
  • Premature and low weight babies
  • Individuals with genetic disorders affecting the absorption and utilization of vitamin E
  • Individuals with fat malabsorption disorders or other serious gastrointestinal disorders (cystic fibrosis, celiac disease, steatorrhea, etc.)
  • Those who are seriously malnourished or whose diet is inadequate in calories or nutrients or who have increased nutritional requirements or a chronic wasting illness
  • Those with pancreatic, liver, gallbladder, or kidney disease, or hypothyroidism
  • Those who are taking estrogen or who have an estrogen imbalance
  • Anyone who has been diagnosed with a vitamin E deficiency
  • People, especially those who are older than 55, who have health issues that may put them at risk and have been advised by their doctor to take vitamin E supplements
  • People whose diets are very low in fat
  • Anyone who has recently undergone surgery or has incurred severe burns or injuries
  • Smokers*
  • Individuals who abuse alcohol or drugs*
  • Those who are under prolonged excess stress
  • Those with heavy exposure to air pollution
  • Those whose diet is high in polyunsaturated fat*
  • Those whose diet includes high concentrations of refined or rancid oils and/or deep fried foods*
*The best and healthiest course of action for these people would be to discontinue or at least greatly cut down on the offending substance, which would also reduce the risk of vitamin E deficiency and might make taking a supplement unnecessary.

Toxicity

Causes
 
Like vitamin E deficiency, vitamin E toxicity is rare. Even when high doses of vitamin E supplements are taken, toxicity might not occur. In fact, vitamin E is probably one of the least toxic of all of the vitamins. There is no evidence of toxicity associated with vitamin E occurring naturally in foods.
 
This finding is interesting because vitamin D, another fat-soluble vitamin, can be highly toxic. However, vitamin E is not stored as readily as other fat-soluble vitamins. Excess intake of vitamin E is usually eliminated from the body within a few days.
 
In addition, the supplementary forms of vitamin E are believed to be less biologically active than the forms that occur naturally in food, thereby protecting most people from the adverse effects that would otherwise be associated with ingesting large amounts. However, high doses of vitamin E have been known to cause excessive bleeding or hemorrhage, along with other disturbing symptoms, in some people. The reason some individuals are affected in this way and others are not may be in part genetic.
 
Extreme caution is necessary for prescribing vitamin E for those affected by rheumatic heart disease, undergoing digitalis, or taking anticoagulants. When vitamin E is taken together with other anticlotting agents, the risk of excessive bleeding is increased since vitamin E itself acts as an anticoagulant.
 
Individuals with high blood pressure also need to be very careful about taking vitamin E supplements because of the possibility that large amounts can raise blood pressure further. Vitamin E in a non-oily, water dispersible form may be the preferred mode of administration for hypertensive individuals.

Symptoms

Vitamin E should not be taken in higher doses than recommended, not only because there is no demonstrable health benefit for doing so, but because too much vitamin E is potentially harmful. Very high doses of vitamin E (over 1,000 IUs daily) can cause the following symptoms, some of which can be serious.  
  • Flatulence
  • Nausea
  • Diarrhea
  • Headache
  • Muscle weakness and fatigue
  • Fainting
  • Double vision
  • Impaired blood coagulation and excessive bleeding
  • Impaired sex functioning
  • Altered metabolism of thyroid, pituitary, and adrenal hormones
Another undesirable effect that can be produced by very high doses of vitamin E is a decrease in the body’s ability to use other fat-soluble vitamins, such as vitamins A and K, effectively. In addition, while small to medium doses of vitamin E are believed to be immune system supportive, it is possible that huge doses may be mildly immune-suppressive.
 
Animal studies have shown that animals fed excessive amounts of vitamin E had impaired bone mineralization, slowed growth, decreased muscle tissue and RBC counts, impaired storage capacity in the liver, and longer blood coagulation times. Human studies have shown increased, rather than decreased, the incidence of cardiac mortality among those who receive high doses of vitamin E supplements.