Vitamin E

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Latest Edit: Hector 2014-3-17 (EDT)

See Also Vitamins


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Article "The Research Behind Vitamin E", NMJ, [2], 2011 December

Vitamin E is a fat-soluble micronutrient. The most active form of vitamin E is known as alpha-tocopherol. Tocopherol in Greek means "to bear children" which underscores its important role in fertility. Vitamin E is incorporated into the fatty lipid portion of cell membranes and carrier molecules where it acts as an important antioxidant against heavy metals and other toxic compounds. Vitamin E also acts as an antioxidant during times of oxidative stress and chronic viral illness thus playing an important role in protecting the immune system.

Contents

Food Sources

The following foods have the highest concentration of vitamin E. For a more expansive list on food sources of specific nutrients visit Health Canada's Dietary Reference Intakes for Vitamins or USDA's National Nutrient Database

The need for vitamin E is dependent on the amount of polyunsaturated fats in the diet. The more polyunsaturated fats in the diet, the greater the need for vitamin E as it plays a significant role as an antioxidant to protects these fats from oxidation. In nature, typically where there are high levels of polyunsaturated fats, there is also vitamin E.

Other food sources include:[1]

  • grains: whole grains (wheat germ).
  • vegetables: asparagus, green leafy vegetables, and tomatoes.
  • fruit: avocados, berries,
  • Other sources include: wheat germ oil, sunflower seed oil, safflower oil, sesame oil, peanut oil, corn oil, olive oil, soybean oil, sunflower seeds, almonds, peanuts.

Uses

The following are the primary uses of Vitamin E. [2] [3]

Article Can Vitamins C and E Improve H. pylori Eradication Rates?, NMJ, [3], 2012 July
  • Antioxidant Protection against Heart Disease and Stroke: Vitamin E has the ability to reduce LDL (bad) cholesterol peroxidation with improvement of plasma LDL breakdown; inhibit excessive platelet aggregation; increase HDL (good) cholesterol; and increase in fibrinolytic activity. Furthermore, vitamin E helps to prevent arterial damage and the oxidation of cholesterol and carrier molecules.
  • Antioxidant Protection against Cancer: Like other antioxidants, vitamin E also has the ability to protect against cancer. Low levels of vitamin E (along with selenium have been shown to increase the risk of certain cancers, namely, gastrointestinal cancers, lung cancer, and oral cancer. The water-soluble succinate derivate has the best the best anticancer properties.
  • Diabetes: Vitamin E has been shown to increase insulin action and is especially important for the prevention of cardiovascular disease associated with diabetes.
  • Research suggests that Vitamin E supplementation improves antioxidant status in Type I Diabetics. Oxidative stress plays a major role in the pathogenesis of Diabetes.[4]
  • Fibrocystic Breast Disease: Vitamin E has been shown to improve several PMS components including fibrocystic breast disease by aiding to normalize hormone levels.
  • Tardive Dyskinesia: Tardive dyskinesias are involuntary movements of the face and mouth which occur most often as a reaction to drugs used to treat schizophrenia. The drugs cause free-radical damage of the nerves innervating the muscles of the face. Vitamin E may protect these nerves from free-radical damage and thus treat tardive dyskinesias in individuals who have been taking antipsychotic drugs for less than 5 years.

Deficiency Symptoms

Vitamin E deficiency is rare but there are 4 conditions where low levels are more common:

  • Fat Malabsorption Syndromes (ex. celiac disease, cystic fibrosis, post-gastrectomy syndrome)
  • Premature Infants
  • Hereditary disorders of red blood cells (ex. sickle cell disease, thalassemia)
  • Hemodialysis patients

Symptoms in adults may include:

  • nerve damage
  • muscle weakness
  • poor co-ordination
  • involuntary movement of the eyes
  • breaking of red blood cells leading to anemia (hemolytic anemia)

In premature infants:

Excess Symptoms

Adverse effects from supplementation are rare but may occur with high doses for extended periods. Symptoms include:

Assessment Procedure

Common Deficiency Tests: [5]

  • Serum Vitamin E - positive test is low.

Prescribing Considerations

  • Natural forms of vitamin E are designated as d-alpha-tocopherol. Synthetic forms are designated as dl-alpha-tocopherol. Only the 'd' form is recognized by the body. It is recommended to use the natural form.
  • The natural form can be found as d-alpha-tocopherol, d-alpha-tocopheryl acetate, and d-alpha-tocopherol succinate.
  • The most active natural form in terms of antioxidant ability is d-alpha-tocopherol. Other forms such as d-beta-, d-gamma, d-delta tocopherol, and a related group of compounds known as tocotrienols also exert antioxidant action.
  • A supplement with mixed tocopherols including the tocotrienols offer the greatest benefit. The d-alpha tocopherol in these supplements is best bound to either acetate or succinate as it makes the compound more stable.
  • There are both water-soluble and fat-soluble forms; the water soluble version does not appear to exert greater benefit over the fat soluble form and is considerably more expensive.[3]
  • The recommended dosages varies based on age and health status. To determine what your specific requirements are talk to your naturopathic doctor or other trained medical professional.
  • Infant (under 1 year): 4.5-6.0 I.U.
  • Child (1-10 years): 9.0-10.5 I.U.
  • Adolescent and Adult: 15 I.U. (Males 11+ years); 12 I.U. (Females 11+ years)
  • Pregnancy: 15 I.U.
  • Lactation: 18 I.U.

Safety

  • Children: Use caution when supplementing in high doses. Problems have arisen in the past with supplementation in infants causing unexpected death, increased frequency of necrotizing enterocolitis, sepsis, and hepatic injury. It was found, however, that these issues were likely related to the solubilizing agent polysorbate instead of the vitamin E. Toxicity is rare but may cause an increase risk of hemorrhage and/or increased bleeding time.
  • Adults: A 2005 meta-analysis showed that doses of vitamin E of >400 I.U. slightly increase the risk of all-cause mortality and that the dose-dependent relationship can actually be seen at doses of 150 I.U./day. There may be some inherent flaws in the studies used for the meta-analysis (ex. vitamin E was used in isolation, the synthetic form was used, patients were used who had pathologies, behaviours, diets, and other factors characterized by high oxidative stress). Further investigation is needed.
  • Pregnancy and Breastfeeding: Monitor levels in pregnancy. One study with women at risk of pre-eclampsia showed a slight elevation in the incidence of small-for-gestational age neonates among women given vitamin C (1000mg) and vitamin E (400 I.U).
  • Contraindications: chronic rheumatic heart disease (avoid initial use of high doses, increase gradually), hypertension, congestive heart failure (large doses of a single antioxidant supplement can contribute to further oxidative stress).
  • Precaution: Caution for individuals with hypersensitivity to vitamin E, source material, or any component of the compound.

Drug Interactions

  • Drug Interactions include:[6]
Supportive or Beneficial:
  • Acetylsalicylic Acid (ASA, aspirin) - Concomitant use may provide additive effects in reducing platelet aggregation and otherwise reducing cerebrovascular risk. Co-adminster aspirin and multiple antioxidants.
  • Anthralin - Combing topical application of vitamin E with drug can provide antioxidant protection against drug-induced lipid peroxidation and inflammation.
  • Cyclosporine - Co-administration may reduce nephrotoxicity and other adverse effects while enhancing its bioavailability and decreasing its clearance and steady-state volume of distribution.
  • Dapsone - Drug may cause hemolysis by damaging red cell membranes. Co-administration of vitamin E may partially protect against drug-induced hemolysis.
  • Doxorubicin and Related Anthracycline Chemotherapy - Oxidative damage contributes to the cardiomyopathy typical of this drug. Vitamin E co-administration may mitigate such adverse effects through its antioxidant activity and enhance tolerance of adverse effects. Synergistic effects also possible.
  • Glyburide - Vitamin E can reduce lipid peroxidation and may enhance glycemic control and improve insulin action. Supplementation, preferably as mixed tocopherols, may be appropriate.
  • Omeprazole and Related Proton Pump Inhibitors - Antioxidant activity of vitamin E may reduce esophagitis and support drug therapy by increasing the mucosal resistance to oxidative damage from gastrointestinal reflux.
Addresses Drug-Induced Deficiency:
  • Bile Acid Sequestrants - Drug may interfere with absorption of vitamin E, folic acid and other fat soluble nutrients. Reasonable probability of clinically significant adverse effect on status of nutrients relevant to cardiovascular health, particularly in at-risk individuals. Supplement away from medication.
  • Gemfibrozil - Drug may reduce serum levels of alpha- and gamma-tocopherol and other antioxidants. Patients with or at risk for cardiovascular disease likely to benefit from a diet rich in vitamin E and other antioxidant nutrients. Role of supplementation contentious.
  • Haloperidol - Free radical production and oxidative damage cause by drug contributes to tardive dyskinesia and other adverse effects and may be caused by drug-induced vitamin E depletion. Co-administer vitamin E, preferably as mixed tocopherols.
  • Orlistat - Drug may decrease absorption of vitamin E and other fat-soluble nutrients.
Other:
  • Chemotherapy and Radiotherapy - Vitamin E and other antioxidants may provide protective activity against lipid peroxidation and other damaging forms of oxidative stress induced by conventional oncological therapies. However, inappropriate or ill-timed usage may interfere with therapies. Avoid concomitant use outside appropriate care.
  • Cisplatin and Oxaliplatin Platinum Chemotherapy - Co-administration may reduce adverse effects of platinum-based chemo due to free-radical damage while compensating for nutrient depletion and potentially enhancing therapeutic efficacy. Avoid concomitant use outside appropriate care.
  • HMG-CoA Reductase Inhibitors (Statins) - Vitamin E may support therapeutic action of statin agents and reduce their adverse effects, particularly on oxidative status; however vitamin E may interfere with therapeutic action of statins, but concerns remain unclear and unsubstantiated. Antioxidant combinations, including vitamin E, may interfere with the HDL-elevating activity of statin-niacin combinations, most likely through their interaction with niacin. Vitamin E may also enhance clearance of statins by promoting detoxification processes. Co-administration may enhance anti-hyperlipidemic therapy and reduce cardiovascular risk. Statin (without niacin) may be compatible with administration of multiple antioxidant combination emphasizing mixed tocopherols.
  • Warfarin and Other Oral Vitamin K Antagonist Anticoagulants - High-dose vitamin E may enhance effects of coumadin-derivative anticoagulants by decreasing vitamin K levels and activity. Further research is needed to determine the nutrient interaction between vitamin K and E in patients using oral anticoagulants and appropriate clinical responses to co-administration. Vigilance is necessary.

Nutrient Interactions

  • Nutrient Interactions include: [6]

References

  1. Medlineplus [1]
  2. Hoffer Abram, Prousky Jonathan (2006) Naturopathic Nutrition, A Guide to Nutrient-Rich Food & Nutritional Supplements for Optimum Health, CCNM Press
  3. 3.0 3.1 Murray Michael T (2005) Encyclopedia of Nutritional Supplements, The Essential Guide for Improving Your Health Naturally, Prima Publishing
  4. Gupta S, Sharma TK, Kaushik GG, Shekhawat VP. (2011) Vitamin E supplementation may ameliorate oxidative stress in type 1 diabetes mellitus patients. Clin Lab;Vol57(5-6):379-86. PMID: 21755829
  5. Bralley J Alexander and Lord Richard S (2005) Laboratory Evaluations in Molecular Medicine, Nutrients, Toxicants, and Cell Regulators Institute for Advances in Molecular Medince, GA
  6. 6.0 6.1 Stargrove Mitchell Bebell, Treasure Jonathan, McKee Dwight L (2008) Herb, Nutrient, and Drug Interactions, Clinical Implications and Therapeutic Strategies. Mosby
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