Vitamin E

We’re busy updating our review of vitamin E and will provide a rating when that’s complete. While we’re working, we share a summary from our predecessor website, Beyond Conventional Cancer Therapies. The information we share here was last updated in November 2020.

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Vitamin E

Key Points

• Before using this therapy, consult your oncology team about interactions with other treatments and therapies. Also make sure this therapy is safe for use with any other medical conditions you may have.
• Vitamin E is a generic term for multiple natural and synthetic compounds, all of which are antioxidants.
• BCCT is interested in vitamin E because some forms may have anticancer properties.
• Vitamin E may reduce side effects of some conventional cancer therapies.
• Vitamin E is included in a number of integrative care cancer protocols.
• No published clinical trials to date describe using vitamin E alone as an anticancer therapy.
• Vitamin E has low toxicity and is usually well tolerated in low doses.
• Vitamin E can cause side effects as well as react with some prescription drugs, including chemotherapy drugs.
• Vitamin E is contraindicated in some medical conditions. Caution and medical supervision are advised.
• Using vitamin E and other antioxidant supplements for cancer is complex, and the evidence is mixed. BCCT advises working with an integrative oncologist, naturopathic oncologist or other clinician with expertise in using supplements in cancer.

Vitamin E is a natural antioxidant found in the following foods:

• Eggs
• Nuts
• Green leafy vegetables
• Wheat germ
• Whole grains
• Plant oils, especially from rice bran, sunflower, safflower, cottonseed and palm

Vitamin E is also available in supplement form.

Natural vitamin E contains eight tocopherols and tocotrienols found in different combinations across sources.1 Most supplements contain only one form of vitamin E—alpha-tocopherol (also written α-tocopherol). Rice bran oil, for comparison, has the full complement of vitamin E forms.2

The specific tocopherols used in studies should be noted, for each have different properties and effects.3  Supplementation with higher levels of alpha-tocopherol may affect levels of gamma-tocopherol; the balance and mix of tocopherols may be very important in outcomes.4

Content consistency can be an issue in supplements: an analysis of seven brands of commercially available vitamin E supplements showed wide discrepancy between the dose listed on the label and actual content of the supplement.5

Practice Guidelines and Recommendations

The US Preventive Services Task Force (USPSTF) recommends against vitamin E supplements for the prevention of cardiovascular disease or cancer.”6

Treating the Cancer

Working against cancer growth or spread, improving survival, or working with other treatments or therapies to improve their anticancer action

No reported clinical trials have used vitamin E as a stand-alone  anticancer treatment. Most of the studies in humans look at its use in combination with drugs or in combination with conventional chemotherapy or radiotherapy.

Lab and Animal Evidence

Managing Side Effects and Promoting Wellness

Managing or relieving side effects or symptoms, reducing treatment toxicity, supporting quality of life or promoting general well-being

Clinical Evidence

Use in combination with drugs or in combination with conventional chemotherapy or radiotherapy shows that vitamin E may reduce side effects such as oral mucositis and peripheral neuropathy, as shown in several small studies,11 although overall evidence is insufficient to recommend use for treating or preventing chemotherapy-induced peripheral neuropathy (CIPN).12

Some evidence shows reduced hot flashes during breast cancer treatment with use.13

Antioxidants including vitamin E may protect against cisplatin-induced toxicity in the kidneys (nephrotoxicity) and the ears (ototoxicity).14

Vitamin E reduces radiotherapy toxicity but is associated with an increase in recurrence of head and neck cancers, especially among smokers.15

Lab and Animal Studies

Reducing Risk

Reducing the risk of developing cancer or the risk of recurrence

The impacts of vitamin E on cancer risk are complex and vary by the form of vitamin E and by the status of other nutrients and genetic backgrounds of individuals.

Dietary Vitamin E

Higher amounts of dietary vitamin E consumed by prostate cancer patients of European-American descent were associated with less aggressive forms of the disease. This was not seen in patients of African-American descent.17

Results published in 2014 of a large-scale randomized trial in men showed vitamin E and C supplementation had no immediate or long-term effects on the risk of total cancers, prostate cancer, or other site-specific cancers.18

Serum Levels of Vitamin E

Findings with prostate cancer:

• Progressively higher PSA scores with decreasing serum levels of vitamin E with in a small study19
• Decreased risk for developing prostate cancer with higher serum alpha-tocopherol levels, with a higher association of decreased risk for advanced prostate cancer and a greater association among those taking alpha-tocopherol supplements20
• Reduced total prostate cancer risk and aggressive cancer risk in current smokers with higher alpha-tocopherol or gamma-tocopherol levels, with some evidence of differences among genotypes21

Patients with colorectal cancer showed lower concentrations of serum vitamin E compared with hospital-based controls in a meta-analysis.22

Supplements

Studies have found inconsistent evidence of effects of vitamin E supplementation on prostate cancer risk:

• Increased risk among healthy men in a large study taking synthetic all rac-alpha-tocopheryl acetate supplements,23 limited to those with lower baseline selenium levels, with indications of differences by genetic types24
• Increased risk from alpha-tocopherol supplementation but decreased risk with gamma-tocopherol use25
• Reduced risk for both prostate cancer and advanced cancer with alpha-tocopherol in a pooled analysis, but no association with gamma-tocopherol26

Analyses of data propose that risks associated with vitamin E may vary by genotype of patients or by the specific form of vitamin E (alpha-tocopherol versus gamma-tocopherol, for instance)27

A 2017 review indicates that studies focusing on alpha-tocopherol supplements may be missing important effects from other forms of vitamin E. The authors of this review found that accumulating research results show that other forms of vitamin E—such as gamma-tocopherol, delta-tocopherol, gamma-tocotrienol, and delta-tocotrienol—have far superior cancer-preventive activities than does alpha-tocopherol. Evidence strongly indicates that these lesser-known vitamin E forms are effective agents for cancer prevention or as adjuvants for improving prevention of cancer.28

Findings on colorectal cancer:

• Most supplements contain α-tocopherol, while a γ-tocopherol-rich mixture of tocopherols inhibits growth of colon and other types of tumors in animals29 and in epidemiological studies30
• Reduced risk of colorectal cancer in women taking unspecified forms of vitamin E supplements31 but not in men taking 400 IU/day of all-rac-α-tocopheryl acetate (see the study for an analysis of whether the correct form was used)32 in large studies
• Other reviews and a meta-analysis concluded no reduced risk with vitamin E or other antioxidants33 (but again, the specific forms of vitamin E may have varying effects).
• No reduced risk of adenoma occurrence34

Optimizing Your Terrain

Creating an environment within your body that does not support cancer development, growth or spread

Clinical Evidence

Vitamin E improved immune activity in patients with advanced colorectal cancer.35

Lab and Animal Evidence

Cautions

Low doses of vitamin E are considered relatively nontoxic. However, vitamin E can cause side effects and drug interactions, some of which can be serious. Daily levels at or above 400 IU are not recommended. Higher levels have been associated with increased mortality:

• Doses greater than 400 IU/day increased all-cause mortality, mostly in patients with chronic diseases. Higher levels of supplements were associated with greater mortality.37
• No increase in mortality at doses up to 800 IU/day was seen in apparently healthy people.38
• Increased mortality was found in mixed studies of healthy individuals and those with diseases.39

Lung cancer patients, especially former or current smokers, “should avoid megadoses of particular antioxidants such as vitamin E and beta-carotene, as well as vitamin A . . . some studies have indicated risks to these patients and to smokers from pro-oxidants formed in the hazardous internal environment that smoking causes.”40

Vitamin E supplementation is linked to increased risk of colorectal adenoma and overall mortality in the general population.41

Some researchers express concerns that vitamin E interferes with chemotherapy and radiation therapy.42

Most vitamin E supplements contain only alpha-tocopherol. Integrative oncologist and BCCT advisor Keith Block, MD. cautions against giving alpha-tocopherol alone, as this may deplete the body of other important components of vitamin E.43

Consult your pharmacist for interactions, and discuss using vitamin E with your doctor. See the following sources for more information on specific side effects, cautions and contraindications:

• Memorial Sloan Kettering Cancer Center: Vitamin E

Access

Vitamin E is widely available in food sources and in supplements.

Dosing

CancerChoices does not recommend therapies or doses, but only provides information for patients and providers to consider as part of a complete treatment plan. Patients should discuss therapies with their physicians, as contraindications, interactions and side effects must be evaluated.

As noted above, levels of active ingredients of natural products can vary widely between and even within products. See Quality and Sources of Herbs, Supplements and Other Natural Products.

Although no optimal vitamin E dose during or after cancer treatment has been established, suggested dosages are listed in these sources:

• Natural Medicines Database (requires purchase)
• Also see the protocols below

Integrative Programs, Protocols and Medical Systems

For more information about programs and protocols, see our Integrative Programs and Protocols page.

Integrative oncology clinicians such as Keith Block, Dwight McKee and Lise Alschuler incorporate vitamin E supplementation into care either during active cancer treatment or after treatment care (or both) to prevent recurrence or secondary cancers.

Programs and protocols

• Alschuler & Gazella complementary approaches44
  • Bladder cancer
  • Breast cancer
  • Cervical cancer
  • Colon cancer
  • Esophageal cancer
  • Gastric cancer
  • Head and neck cancer
  • Kidney cancer
  • Ovarian cancer
  • Thyroid cancer
  • Guidance for support during conventional treatment and for treatment recovery
• Bastyr University Integrative Oncology Research Center protocol for stage IV breast cancer45
• Block program46 (select tocopherols)
• Chemopreventive nutraceutical in remission maintenance program:
  • Brain cancer
  • Breast cancer
  • Colon cancer
  • Leukemia case
  • Prostate cancer
  • Core diet plan
  • Combination antioxidant support formula and terrain modification
  • Anti-inflammatory support
  • Immune surveillance booster
  • Circulatory support supplement
  • Remission maintenance program
• Lemole, Mehta & McKee protocols47 (select tocopherols)
  • Bladder cancer
  • Lung cancer
  • Prostate cancer
• MacDonald breast cancer program48
• McKinney protocols49 (select tocopherols)
  • General cancer
  • Bladder cancer
  • Brain/nerve cancer
  • Breast cancer
  • Carcinoid/neuroendocrine cancer
  • Cervical cancer
  • Colorectal cancer
  • Esophageal cancer
  • Head and neck cancer
  • Kidney cancer
  • Leukemia and myelodysplastic syndrome
  • Lymphoma
  • Multiple myeloma
  • Prostate cancer
  • Skin cancer
  • Stomach cancer
  • Thyroid cancer
  • Uterine cancer

Commentary

Integrative oncologist and CancerChoices advisor Donald Abrams, MD, recommends against use of vitamin E supplements.50

According to Raymond Chang, MD, tocotrienols are much more potent than the tocopherol form of E vitamins, especially gamma-tocotrienol, and especially against cancer.51

Integrative oncologist and CancerChoices advisor Keith Block, MD: “Avoid high doses of single antioxidant supplements . . . Labile antioxidants—which include vitamins A, C and E, selenium and beta-carotene—can change into pro-oxidants . . . Thus they can increase the oxidative stress of your terrain and, if used without proper supervision, enhance the growth and spread of cancer cells. Used in the right dosages and combinations, however, they can help control malignancy.”52 Dr. Block advises using antioxidants like vitamin E in a mix of diverse antioxidants to promote a synergistic effect.53

Nutrition Advisor Karen Collins, MS, RDN, CDN, FAND, from the American Institute for Cancer Research, July 26, 2019: There are multiple reasons to be cautious about alpha-tocopherol supplements much beyond RDA level. I cannot find evidence of an effect on absorption of tocotrienols and other tocopherols, but it has been known for many years that high levels of alpha-tocopherol intake tend to decrease blood and tissue levels of gamma-tocopherol. (I’m not sure of the reason—perhaps through effects on absorption from the gut, but perhaps on saturation of metabolic enzymes, preferential saturation of carriers within the body, or other mechanisms.)

While there is great interest in the potential of tocopherols and tocotrienols beyond alpha-tocopherol for anticancer effects, these ideas are largely based on in vitro and animal studies. There is a big leap from these kinds of studies to human application, which need to consider dose, bioavailability, potential differences among human populations.

However, it’s important to think more broadly about your question, too. Our antioxidant defense network (from exogenous sources and endogenous elements within our body) interact in many ways. So setting any single element high may have ramifications on others. Selenium is one example, which is noted in the references I share below and is still coming up in studies as recently as May.

Perhaps this summary of research and recommendations written for health professionals will be helpful to you: National Institutes of Health Vitamin E: Fact Sheet for Health Professionals. It focuses on alpha-tocopherol, since that is the only form for which we have established recommended intake at this time. The reason I recommend it for your review is that it provides important perspective on potential for excess. Although the Tolerable Upper Intake Levels (set to accompany the RDAs) were developed based on avoidance of hemorrhagic effects, evidence from studies like the SELECT trial show that problems such as increased risk of prostate cancer can occur at levels above the RDA but well below that upper limit. (Remember back in the day when cardiologists were excited to recommend 400 IU to all their heart patients??)

There is also a version written for the public, in case you’d like to link to it in what you’re creating: Vitamin E: Fact Sheet for Consumers.

Another reference that may help explain the strong findings about the dangers of antioxidant supplements during cancer treatment: Avoiding Antioxidant-Drug Interactions During Cancer Treatment.

My bottom line: Concern about interactions of alpha-tocopherol supplements with tocotrienols and other tocopherols is only one of several reasons to be concerned about supplementation beyond the RDA, especially well beyond it.

Also known by these names

• Tocopherol (alpha, beta, gamma and delta)
• Tocotrienol (alpha, beta, delta and gamma)
• RRR-alpha-tocopherol (synthetic)

Helpful links

• National Institutes of Health: Vitamin E Fact Sheet for Health Professionals
• TRC Natural Medicines Database: Vitamin E (subscription required): in-depth information, ratings of effectiveness and safety and evaluation of specific resveratrol products
• Consumer Labs: Product Review (subscription required): Vitamin E Supplements, Cream, and Oil (Including Tocopherols and Tocotrienols)
• Moss Reports (purchase required): Select from the list of cancers down the left side of the page for a report describing uses of conventional, complementary, alternative and integrative therapies related to that cancer. Ralph Moss is among the most knowledgeable and balanced researchers of integrative cancer therapies. The cost of his Moss Reports is not negligible, but many patients find them of considerable value. Moss is also available for consultations. 
• Gurdev Parmar and Tina Kaczor: Textbook of Naturopathic Oncology: A Desktop Guide of Integrative Cancer Care. 1st edition
• Dawn Lemanne and Victoria Maizes: Advising Women Undergoing Treatment for Breast Cancer
• National Cancer Institute at the National Institutes of Health: PDQ® Cancer Information Summaries
• Raymond Chang, MD: Beyond the Magic Bullet: The Anti-Cancer Cocktail
• Donald I. Abrams, MD, and Andrew T. Weil, MD: Integrative Oncology, 2nd Edition
• Neil McKinney, BSc, ND: Naturopathic Oncology, 3rd Edition
• Lise Alschuler, ND, FABNO, and Karolyn Gazella: The Definitive Guide to Cancer, 3rd Edition
• Keith I. Block, MD: Life over Cancer: The Block Center Program for Integrative Cancer Treatment
• Memorial Sloan Kettering Cancer Center: About Herbs, Botanicals and Other Products
• National Cancer Institute: Complementary and Alternative Medicine for Health Professionals
• National Cancer Institute: Office of Cancer Complementary and Alternative Medicine
• Michael Lerner: Choices In Healing: Integrating the Best of Conventional and Complementary Approaches to Cancer

References

1. Vitamin E Fact Sheet for Health Professionals. National Institutes of Health Office of Dietary Supplements. July 10, 2019. Viewed July 17, 2019; Block KI. Life over Cancer: The Block Center Program for Integrative Cancer Treatment. New York: Bantam Dell. 2009.
2. Block KI. Life over Cancer: The Block Center Program for Integrative Cancer Care. New York: Bantam Dell. 2009. p. 538.
3. Aggarwal B, Nesaretnam K. Vitamin E tocotrienols: life beyond tocopherols. Genes & Nutrition. 2012 Jan;7(1):1.
4. Ledesma MC, Jung-Hynes B et al. Selenium and vitamin E for prostate cancer: post-SELECT (Selenium and Vitamin E Cancer Prevention Trial) status. Molecular Medicine. 2011 Jan-Feb;17(1-2):134-43.
5. Feifer AH, Fleshner NE, Klotz L. Analytical accuracy and reliability of commonly used nutritional supplements in prostate disease. Journal of Urology. 2002;168:150-4.
6. Moyer VA; U.S. Preventive Services Task Force. Vitamin, mineral, and multivitamin supplements for the primary prevention of cardiovascular disease and cancer: U.S. Preventive services Task Force recommendation statement. Annals of Internal Medicine. 2014;160(8):558-564
7. Chang R. Beyond the Magic Bullet: The Anti-Cancer Cocktail. New York: Square One Publishers. 2012. p. 128.
8. Sayin VI, Ibrahim MX et al. Antioxidants accelerate lung cancer progression in mice. Science Translational Medicine. 2014 Jan 29;6(221):221ra15.
9. Wiel C, Le Gal K et al. BACH1 stabilization by antioxidants stimulates lung cancer metastasis. Cell. 2019 Jul 11;178(2):330-345.e22.
10. Jiang Q. Natural forms of vitamin E as effective agents for cancer prevention and therapy. Advances in Nutrition. 2017 Nov 15;8(6):850-867.
11. Chaitanya NC, Muthukrishnan A et al. Role of vitamin E and vitamin A in oral mucositis induced by cancer chemo/radiotherapy—a meta-analysis. Journal of  Clinical & Diagnostic Research. 2017 May;11(5):ZE06-ZE09; Brami C, Bao T, Deng G. Natural products and complementary therapies for chemotherapy-induced peripheral neuropathy: a systematic review. Critical Reviews in Oncology/Hematology. 2016 Feb;98:325-34; Samuels N, Schiff E, Ben-Arye E. Non-herbal nutritional supplements for symptom relief in adjuvant breast cancer: creating a doctor-patient dialogue. BMJ Supportive & Palliative Care. 2014 Sep;4(3):e1; Mondal S, Choudhury KB, Sharma S, Gupta A, DuttaS. Comparative study among glutamine, acetyl-L-carnitine, vitamin-E and methylcobalamine for treatment of paclitaxel-induced peripheral neuropathy. Clinical Cancer Investigation Journal. 2014;3(3):213-219; Argyriou AA, Chroni E et al. Vitamin E for prophylaxis against chemotherapy-induced neuropathy: a randomized controlled trial. Neurology. 2005 Jan 11;64(1):26-31; Pace A, Savarese A et al. Neuroprotective effect of vitamin E supplementation in patients treated with cisplatin chemotherapy. Journal of Clinical Oncology. 2003 Mar 1;21(5):927-31..
12. Schloss JM, Colosimo M, Airey C, Masci PP, Linnane AW, Vitetta L. Nutraceuticals and chemotherapy induced peripheral neuropathy (CIPN): a systematic review [published correction appears in Clinical Nutrition. 2015 Feb;34(1):167]. Clinical Nutrition. 2013;32(6):888–893; ; Albers JW, Chaudhry V, Cavaletti G, Donehower RC. Interventions for preventing neuropathy caused by cisplatin and related compounds. Cochrane Database of Systematic Reviews. 2014;(3):CD005228.
13. Greenlee H, Hershman DL, Jacobson JS. Use of antioxidant supplements during breast cancer treatment: a comprehensive review. Breast Cancer Research and Treatment. 2009 Jun;115(3):437-52.
14. Hakiminia B, Goudarzi A, Moghaddas A. Has vitamin E any shreds of evidence in cisplatin-induced toxicity. Journal of Biochemical and Molecular Toxicology. 2019 May 21:e22349.
15. Harvie M. Nutritional supplements and cancer: potential benefits and proven harms. American Society of Clinical Oncology Educational Book. 2014;e478-e486.
16. Leonetti C, Biroccio A et al. Alpha-tocopherol protects against cisplatin-induced toxicity without interfering with antitumor efficacy. International Journal of Cancer. 2003;104(2):243-250.
17. Antwi SO, Steck SE et al. Dietary, supplement, and adipose tissue tocopherol levels in relation to prostate cancer aggressiveness among African and European Americans: The North Carolina-Louisiana Prostate Cancer Project (PCaP). Prostate. 2015 Sep;75(13):1419-35.
18. Wang L, Sesso HD et al. Vitamin E and C supplementation and risk of cancer in men: posttrial follow-up in the Physicians’ Health Study II randomized trial. American Journal of Clinical Nutrition. 2014 Sep;100(3):915-23.
19. Adaramoye OA, Akinloye O, Olatunji IK. Trace elements and vitamin E status in Nigerian patients with prostate cancer. African Health Sciences. 2010 Mar;10(1):2-8.
20. Weinstein SJ, Wright ME et al. Serum and dietary vitamin E in relation to prostate cancer risk. Cancer Epidemiology, Biomarkers & Prevention. 2007 Jun;16(6):1253-9.
21. Cheng TY, Barnett MJ et al. Genetic variation in myeloperoxidase modifies the association of serum α-tocopherol with aggressive prostate cancer among current smokers. Journal of Nutrition. 2011 Sep;141(9):1731-7.
22. Dong Y, Liu Y et al. Link between risk of colorectal cancer and serum vitamin E levels: a meta-analysis of case-control studies. Medicine (Baltimore). 2017 Jul;96(27):e7470.
23. Klein EA, Thompson IM Jr et al. Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). JAMA. 2011 Oct 12;306(14):1549-56.
24. Kristal AR, Darke AK et al. Baseline selenium status and effects of selenium and vitamin e supplementation on prostate cancer risk. Journal of the National Cancer Institute. 2014 Mar;106(3):djt456; Chan JM, Darke AK et al. Selenium- or vitamin E-related gene variants, interaction with supplementation, and risk of high-grade prostate cancer in SELECT. Cancer Epidemiology, Biomarkers & Prevention. 2016 Jul;25(7):1050-1058.
25. Vance TM, Su J, Fontham ET, Koo SI, Chun OK. Dietary antioxidants and prostate cancer: a review. Nutrition and Cancer. 2013;65(6):793-801.
26. Key TJ, Appleby PN et al. Carotenoids, retinol, tocopherols, and prostate cancer risk: pooled analysis of 15 studies. American Journal of Clinical Nutrition. 2015 Nov;102(5):1142-57.
27. Vance TM, Su J, Fontham ET, Koo SI, Chun OK. Dietary antioxidants and prostate cancer: a review. Nutrition and Cancer. 2013;65(6):793-801.
28. Jiang Q. Natural forms of vitamin E as effective agents for cancer prevention and therapy. Advances in Nutrition. 2017 Nov 15;8(6):850-867.
29. Ju J, Picinich SC, et al. Cancer-preventive activities of tocopherols and tocotrienols. Carcinogenesis. 2010;31(4):533-542; Yang CS, Suh N, Kong AN. Does vitamin E prevent or promote cancer? Cancer Prevention Research (Philadelphia). 2012;5(5):701-705.
30. Campbell S, Stone W, Whaley S, Krishnan K. Development of gamma (gamma)-tocopherol as a colorectal cancer chemopreventive agent. Critical Reviews in Oncology/Hematology. 2003;47(3):249-259.
31. Stone WL, Krishnan K, Campbell SE, Palau VE. The role of antioxidants and pro-oxidants in colon cancer. World Journal of Gastrointestinal Oncology. 2014 Mar 15;6(3):55-66.
32. Lippman SM, Klein EA et al. Effect of selenium and vitamin E on risk of prostate cancer and other cancers: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). JAMA. 2009 Jan 7;301(1):39-51.
33. Papaioannou D, Cooper KL et al. Antioxidants in the chemoprevention of colorectal cancer and colorectal adenomas in the general population: a systematic review and meta-analysis. Colorectal Disease. 2011 Oct;13(10):1085-99; Arain MA, Abdul Qadeer A. Systematic review on “vitamin E and prevention of colorectal cancer”. Pakistan Journal of Pharmaceutical Sciences. 2010 Apr;23(2):125-30; Harvie M. Nutritional supplements and cancer: potential benefits and proven harms. American Society of Clinical Oncology Educational Book. 2014;e478-e486.
34. Lance P, Alberts DS et al. Colorectal adenomas in participants of the SELECT randomized trial of selenium and vitamin E for prostate cancer prevention. Cancer Prevention Research (Philadelphia). 2017 Jan;10(1):45-54.
35. Hanson MG, Ozenci V et al. A short-term dietary supplementation with high doses of vitamin E increases NK cell cytolytic activity in advanced colorectal cancer patients. Cancer Immunology, Immunotherapy. 2007;56(7):973-984; Malmberg KJ, Lenkei R et al. A short-term dietary supplementation of high doses of vitamin E increases T helper 1 cytokine production in patients with advanced colorectal cancer. Clinical Cancer Research. 2002 Jun;8(6):1772-8.
36. Chang R. Beyond the Magic Bullet: The Anti-Cancer Cocktail. New York: Square One Publishers. 2012. p. 128.
37. Miller ER 3rd, Pastor-Barriuso R et al. Meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality. Annals of Internal Medicine. 2005 Jan 4;142(1):37-46.
38. Curtis AJ, Bullen M, Piccenna L, McNeil JJ. Vitamin E supplementation and mortality in healthy people: a meta-analysis of randomised controlled trials. Cardiovascular Drugs and Therapy. 2014 Dec;28(6):563-73.
39. Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C. Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database of Systematic Reviews. 2012 Mar 14;(3):CD007176.
40. Block KI. Life over Cancer: The Block Center Program for Integrative Cancer Care. New York: Bantam Dell. 2009. p. 312.
41. Harvie M. Nutritional supplements and cancer: potential benefits and proven harms. American Society of Clinical Oncology Educational Book. 2014;e478-e486.
42. Lawenda BD, Kelly KM et al. Should supplemental antioxidant administration be avoided during chemotherapy and radiation therapy? Journal of the National Cancer Institute. 2008 Jun 4;100(11):773-83.
43. Block KI. Life over Cancer: The Block Center Program for Integrative Cancer Treatment. New York: Bantam Dell. 2009.
44. Alschuler LN, Gazella KA. The Definitive Guide to Cancer, 3rd Edition: An Integrative Approach to Prevention, Treatment, and Healing. Berkeley, California: Celestial Arts. 2010; Alschuler LN, Gazella KA. The Definitive Guide to Thriving after Cancer: A Five-Step Integrative Plan to Reduce the Risk of Recurrence and Build Lifelong Health. Berkeley, California: Ten Speed Press. 2013.
45. McKinney N. Naturopathic Oncology, 3rd Edition. Victoria, BC, Canada: Liaison Press. 2016. p. 316.
46. Block KI. Life over Cancer: The Block Center Program for Integrative Cancer Treatment. New York: Bantam Dell. 2009.
47. Lemole G, Mehta P, McKee D. After Cancer Care: The Definitive Self-Care Guide to Getting and Staying Well for Patients with Cancer. New York, New York: Rodale, Inc. 2015.
48. MacDonald B. The Breast Cancer Companion: A Complementary Care Manual: Third Edition. (self-published, Amazon, 2016).
49. McKinney N. Naturopathic Oncology, 3rd Edition. Victoria, BC, Canada: Liaison Press. 2016.
50. Abrams DI. An integrative approach to prostate cancer. The Journal of Alternative and Complementary Medicine. Volume 24, Numbers 9 and 10, 2018, pp. 872–880.
51. Chang R. Beyond the Magic Bullet: The Anti-Cancer Cocktail. New York: Square One Publishers. 2012. p. 128.
52. Block KI.. Life over Cancer: The Block Center Program for Integrative Cancer Care. New York: Bantam Dell. 2009. p. 310.
53. Block KI.. Life over Cancer: The Block Center Program for Integrative Cancer Care. New York: Bantam Dell. 2009. p. 311-313.