II. Sources

  1. Vegetable Oil
    1. Corn oil
    2. Cottonseed oil
    3. Sunflower oil
    4. Soybean oil
  2. Wheat germ
  3. Fish liver oil
  4. Nuts

III. Mechanism

  1. Vegetable and Seed Oils: gamma-tocopherol
    1. Antioxidant
    2. Usual daily intake 15 IU/day
  2. Supplements: alpha-tocopherol
    1. Blocks antioxidant effect of natural foods
    2. May have pro-oxidant effect
      1. S Christen (1997) Proc Natl Acad Sci 64:3217 [PubMed]

IV. Efficacy: Potential Benefits

  1. May delay progression of Alzheimer's Disease
    1. May slow functional decline in mild to moderate Dementia (in those on Cholinesterase Inhibitor)
      1. Dysken (2014) JAMA 311(1):33-44 [PubMed]
    2. Initial studies showed slower functional decline
      1. Sano (1997) N Engl J Med 336:1216-22 [PubMed]
    3. Insufficient evidence to recommend by Cochrane
      1. Tabet (2003) Cochrane Database Syst Rev, CD002854 [PubMed]
  2. May boost immune response in elderly
    1. Study (DBPCT) of those over age 65 years (n=88)
      1. Measured Antigen produced induration to PPD
      2. Marked increase induration with 200 mg/day
      3. Suggested that US RDA (30 mg) may be too low
    2. References
      1. Meydani (1997) JAMA 277:1380-6 [PubMed]

V. Adverse Effects: Potential Risks or No Benefit

  1. Increased overall motality risk
    1. Associated with consistent dosing >400 IU/day for >1 year
  2. Does not reduce cancer risk
    1. Prostate Cancer risk is increased (1 new case in 625 men taking 400 units/day)
    2. Klein (2011) JAMA 306:1549-56. [PubMed]
  3. Congestive Heart Failure increased risk
  4. Coronary Artery Disease risk
    1. Initial studies suggested possible benefit
    2. PPP Study suggests no benefit
    3. May increase Heart Failure risk
    4. PPP study shows possibly higher CVA risk
    5. Studies show slightly higher all cause mortality
  5. Increased risk of bleeding and Hemorrhagic Stroke
    1. Interference with Vitamin K metabolism, antagonizing Vitamin K dependent Clotting Factors
    2. Interference with platelet aggregation
    3. Do not use >800 IU/day in patients on Warfarin or antiplatelet agents
    4. Schurks (2010) BMJ 341: c5702 [PubMed]

VI. References

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Ontology: Vitamin E (C0042874)

Definition (MEDLINEPLUS)

Vitamin E is an antioxidant. Antioxidants are substances that may protect your cells against the effects of free radicals. Free radicals are molecules produced when your body breaks down food, or by environmental exposures like tobacco smoke and radiation. Vitamin E also plays a role in your immune system and metabolic processes. Good sources of vitamin E are vegetable oils, margarine, nuts, seeds, and leafy greens. Vitamin E is also added to foods like cereals. Most people get enough vitamin E from the foods they eat. People with certain disorders, such as liver diseases, cystic fibrosis, and Crohn's disease may need extra vitamin E.

Vitamin E supplements may be harmful for people who take blood thinners and other medicines. Check with your health care provider before taking the supplements.

NIH: National Institutes of Health Office of Dietary Supplements

Definition (NCI) A natural fat-soluble antioxidant with potential chemopreventive activity. Also known as tocopherol, vitamin E ameliorates free-radical damage to biological membranes, protecting polyunsaturated fatty acids (PUFA) within membrane phospholipids and within circulating lipoproteins. Peroxyl radicals react 1000-fold faster with vitamin E than with PUFA. In the case of oxygen free radical-mediated tumorigenesis, vitamin E may be chemopreventive. (NCI04)
Definition (NCI_CRCH) A fat-soluble vitamin which is primarily a chain-breaking antioxidant that prevents the propagation of lipid peroxidation.
Definition (NCI_NCI-GLOSS) A nutrient that the body needs in small amounts to function and stay healthy. Vitamin E helps prevent cell damage caused by free radicals (highly reactive chemicals). It is fat-soluble (can dissolve in fats and oils) and is found in seeds, nuts, leafy vegetables, and vegetable oils. Not enough vitamin E can result in infertility (the inability to produce children). It is being studied in the prevention and treatment of some types of cancer. Vitamin E is a type of antioxidant.
Definition (MSH) A generic descriptor for all TOCOPHEROLS and TOCOTRIENOLS that exhibit ALPHA-TOCOPHEROL activity. By virtue of the phenolic hydrogen on the 2H-1-benzopyran-6-ol nucleus, these compounds exhibit varying degree of antioxidant activity, depending on the site and number of methyl groups and the type of ISOPRENOIDS.
Definition (PDQ) A natural fat-soluble antioxidant with potential chemopreventive activity. Also known as tocopherol, vitamin E ameliorates free-radical damage to biological membranes, protecting polyunsaturated fatty acids (PUFA) within membrane phospholipids and within circulating lipoproteins. Peroxyl radicals react 1000-fold faster with vitamin E than with PUFA. In the case of oxygen free radical-mediated tumorigenesis, vitamin E may be chemopreventive. Check for "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=38321&idtype=1" active clinical trials or "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=38321&idtype=1&closed=1" closed clinical trials using this agent. ("http://nciterms.nci.nih.gov:80/NCIBrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&code=C942" NCI Thesaurus)
Concepts Pharmacologic Substance (T121) , Lipid (T119) , Vitamin (T127)
MSH D014810
SnomedCT 37237003, 63822004
English Vitamin E, 3,4-Dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-ol, 5,7,8-Trimethyltocol, VIT E, E vitamin, vitamin-E, Vitamin E Compound, vitamin E (medication), Vitamin E [Chemical/Ingredient], VITAMIN E, vit e, vitamin E, tocopherol (vit E), tocopherol, 2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)chroman-6-ol, Vitamin E preparation, Vitamin E product, Vitamin E (substance), Vitamin E preparation (product), VIT-E, Vitamin E preparation, NOS, Vitamin E preparation (substance), E Vitamin
Swedish Vitamin E
Czech vitamin E
Finnish Tokoferoli
Russian TOKOFEROL, VITAMIN E, ВИТАМИН E, ТОКОФЕРОЛ
Spanish producto con vitamina E, vitamina E (producto), preparado con vitamina E (producto), preparado con vitamina E, preparado de vitamina E (sustancia), vitamina E (sustancia), vitamina E, Vitamina E
Croatian VITAMIN E
Polish Tokoferol, Witamina E
French Vitamine E
German Vitamin E
Italian Vitamina E
Portuguese Vitamina E

Ontology: alpha Tocopherol (C0969677)

Definition (NCI) A naturally-occurring form of vitamin E, a fat-soluble vitamin with potent antioxidant properties. Considered essential for the stabilization of biological membranes (especially those with high amounts of polyunsaturated fatty acids), d-alpha-Tocopherol is a potent peroxyl radical scavenger and inhibits noncompetitively cyclooxygenase activity in many tissues, resulting in a decrease in prostaglandin production. Vitamin E also inhibits angiogenesis and tumor dormancy through suppressing vascular endothelial growth factor (VEGF) gene transcription. (NCI04)
Definition (NCI) A naturally-occurring form of vitamin E, a fat-soluble vitamin with potent antioxidant properties. Considered essential for the stabilization of biological membranes (especially those with high amounts of polyunsaturated fatty acids), d-alpha-Tocopherol is a potent peroxyl radical scavenger and inhibits noncompetitively cyclooxygenase activity in many tissues, resulting in a decrease in prostaglandin production. Vitamin E also inhibits angiogenesis and tumor dormancy through suppressing vascular endothelial growth factor (VEGF) gene transcription. (NCI04)
Definition (NCI_CRCH) Tocopherol with three methyl groups on its chromanol ring.
Definition (MSH) A natural tocopherol and one of the most potent antioxidant tocopherols. It exhibits antioxidant activity by virtue of the phenolic hydrogen on the 2H-1-benzopyran-6-ol nucleus. It has four methyl groups on the 6-chromanol nucleus. The natural d form of alpha-tocopherol is more active than its synthetic dl-alpha-tocopherol racemic mixture.
Concepts Pharmacologic Substance (T121) , Lipid (T119) , Vitamin (T127)
MSH D024502
SnomedCT 63822004, 259666007, 350546004, 116776001, 37237003
LNC LP15369-9, MTHU004905
English alpha-Tocopherol, Alpha tocopheryl product, d-Alpha-Tocopherol, (+/-)-alpha-Tocopherol, d-alpha-Tocopherol, (+)-alpha-Tocopherol, d-alpha tocopherol, Alfa tocopherol, Alpha tocopherol, alpha-tocopherols, alpha-tocopherols (medication), (+-)-alpha-Tocopherol, alpha-Tocopherol [Chemical/Ingredient], Alpha-Tocopherol, alpha-tocopherol, ALPHA-TOCOPHEROL, D-, ALPHA-TOCOPHEROL, d-alpha-tocopherol, d alpha tocopherol, dl-alpha tocopherol, alpha tocopherol, ALPHA-Tocopherol, .Alpha.-Tocopherol, .alpha.-tocopherol, 3,4-Dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-ol, .Alpha.-tocopherol, .ALPHA.-TOCOPHEROL, D-, .ALPHA.-TOCOPHEROL, .Alpha.-Tocopherol, D-, .ALPHA.-Tocopherol, R,R,R-alpha-Tocopherol, Tocopherol, d-alpha, d alpha Tocopherol, d-alpha Tocopherol, Alpha tocopheryl product (product), 2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)chroman-6-ol, .alpha.-tocopherol, d-, D-alpha-tocopherol, alpha-Tocopherol preparation, Alpha-tocopherol, D-alpha-tocopherol (substance), Alpha-tocopherol (substance), alpha Tocopherol
Swedish Alfatokoferol
Czech alfa-tokoferol
Spanish alfa-tocoferol, tocofersolán, preparado con alfa-tocoferol, Alfa Tocoferol, alfa - tocoferol (sustancia), alfa - tocoferol, d - alfa - tocoferol (sustancia), d - alfa - tocoferol, alfa-Tocoferol
Finnish Alfatokoferoli
Russian AL'FA-TOKOFEROL, АЛЬФА-ТОКОФЕРОЛ
Japanese アルファ-トコフェロール, d-α-トコフェロール
Polish Alfa-tokoferol
French alpha-Tocophérol, Tocophérol alpha
German Alpha-Tokopherol
Italian Tocoferolo alfa
Portuguese alfa-Tocoferol