| 词条 | Megavitamin therapy |
| 释义 |
|image = |image_width = |caption = |claims = Health effects from very high doses of vitamins. |topics = vitamins, dietary supplements |origyear = 1930s |origprop = |currentprop = |notableprop = Frederick Klenner, Linus Pauling }}{{Alternative medicine sidebar}}Megavitamin therapy is the use of large doses of vitamins, often many times greater than the recommended dietary allowance (RDA) in the attempt to prevent or treat diseases. Megavitamin therapy is typically used in alternative medicine by practitioners who call their approach orthomolecular medicine.[1] Vitamins are useful in preventing and treating illnesses specifically associated with dietary vitamin shortfalls, but the conclusions of medical research are that the broad claims of disease treatment by advocates of megavitamin therapy are unsubstantiated by the available evidence.[2][3] It is generally accepted that doses of any vitamin greatly in excess of nutritional requirements will result either in toxicity (vitamins A and D) or in the excess simply being metabolised; thus evidence in favour of vitamin supplementation supports only doses in the normal range.[4][5][6] Critics have described some aspects of orthomolecular medicine as food faddism or even quackery.[7][8][9] Research on nutrient supplementation in general suggests that some nutritional supplements might be beneficial, and that others might be harmful;[10][11][12] several specific nutritional therapies are associated with an increased likelihood of the condition they are meant to prevent.[13] Multivitamin vs megavitaminMegavitamin therapy must be distinguished from the usual 'vitamin supplementation' approach of traditional multivitamin pills. Megavitamin doses are far higher than the levels of vitamins ordinarily available through western diets. A study of 161,000 individuals (post-menopausal women) provided, in the words of the authors, "convincing evidence that multivitamin use has little or no influence on the risk of common cancers, cardiovascular disease, or total mortality in postmenopausal women".[14] HistoryIn the 1930s and 1940s, some scientific and clinical evidence suggested that there might be beneficial uses of vitamins C, E, and niacin in large doses. Beginning in the 1930s, the Shutes in Canada developed a megadose vitamin E therapy for cardiovascular and circulatory complaints, naming it the "Shute protocol".[15] Tentative experiments in the 1930s[16] with larger doses of vitamin C led to Frederick Klenner's development of megadose intravenous vitamin C treatments for polio and other viruses in the 1940s.[17] William Kaufman published articles in the 1940s that detailed his treatment of arthritis with frequent, high doses of niacinamide.[18] Rudolf Altschul and Abram Hoffer applied large doses of the immediate release form of niacin (Vitamin B3) to treat hypercholesterolemia.[19][20] In a 1956 publication entitled Biochemical Individuality, Roger J. Williams introduced concepts for individualized megavitamins and nutrients.[21] Megavitamin therapies were also publicly advocated by Linus Pauling in the late 1960s.[22] Usage as therapyAlthough megavitamin therapies still largely remain outside of the structure of evidence-based medicine, they are increasingly used by patients, with or without the approval of their treating physicians, often after recommendations by practitioners of orthomolecular and naturopathic medicine.[23] The proposed efficacy of various megavitamin therapies to reduce cancer risk has been contradicted by results of one clinical trial.[24] Vitamin C{{Main|Vitamin C megadosage}}The US Recommended Dietary Allowance for vitamin C for adult women is 76 mg/day and for adult men 90 mg/day. Although Linus Pauling was known for highly respectable research in chemistry and biochemistry, he was also known for promoting the consumption of vitamin C in large doses.[25] Although he claimed and stood firm in his claim that consuming over 1,000 mg is helpful for one’s immune system when fighting a head cold, the results of empirical research do not align with this view. A meta-analysis concluded that supplementary vitamin C significantly lowered serum uric acid, considered a risk factor for gout.[26] One population study reported an inverse correlation between dietary vitamin C and risk of gout.[27] A review of clinical trials in the treatment of colds with small and large doses of Vitamin C has established that there is no evidence that it decreases the incidence of common colds.[28] After 33 years of research, it is still not established whether vitamin C can be used as a treatment for cancer.[29] Vitamin EThe US Recommended Dietary Allowance for vitamin E for adult women and men is 15 mg/day. The US Food and Nutrition Board set a Tolerable upper intake level (UL) at 1,000 mg (1,500 IU) per day derived from animal models that demonstrated bleeding at high doses.[30] In the US, the popularity for vitamin E as a dietary supplement–popular doses 400, 800 and 1000 IU/day–peaked around 2000. Declines in usage were attributed to publications of studies that showed either no benefits or negative consequences from vitamin E supplements.[31] One meta-analysis showed no association between vitamin E supplementation and cardiovascular events (nonfatal stroke or myocardial infarction) or cardiovascular mortality.[32] Another meta-analysis concluded that high-dosage vitamin E increased all-cause mortality.[33] NiacinThe US Recommended Dietary Allowance for niacin for adult women is 14 mg/day and for adult men 16 mg/day. Niacin is available as a prescription product, either immediate release (500 mg tablets; prescribed up to 3,000 mg/day) or extended release (500 and 1,000 mg tablets; prescribed up to 2,000 mg/day). In the US, niacin is also available as a dietary supplement at 500 to 1,000 mg/tablet. Niacin has sometimes been used in combination with other lipid-lowering medications.[34] Systematic reviews found no effect of niacin on cardiovascular disease or death, in spite of raising high-density lipoprotein (HDL) cholesterol. Reported side effects include an increased risk of diabetes.[35][36][37] See alsoRelated topics
Vitamin topics
References1. ^{{cite journal |vauthors=Zell M, Grundmann O |title=An orthomolecular approach to the prevention and treatment of psychiatric disorders |journal=Adv Mind Body Med |volume=26 |issue=2 |pages=14–28 |date=2012 |pmid=23341413 |doi= |url=}} 2. ^{{cite book |vauthors=Aaronson S, etal |title=Cancer medicine 6 (Frei, Emil; Kufe, Donald W.; Holland, James F., eds)|publisher=BC Decker |location=Hamilton, Ont |year=2003|pages=76|isbn=978-1-55009-213-4 |chapter= Cancer medicine }} 3. ^{{cite journal |author1=Nutrition Committee |author2=Canadian Paediatric Society | date=1990| title = Megavitamin and megamineral therapy in childhood. Nutrition Committee, Canadian Paediatric Society | journal = CMAJ | volume = 143 | issue = 10 | pages = 1009–1013 | pmid = 1699646 | pmc = 1452516 }} 4. ^{{Cite web | url=http://healthyeating.sfgate.com/body-excess-vitamin-b-c-might-consume-3056.html | title=What Does Your Body do to Excess Vitamin B or C That You Might Consume?}} 5. ^{{Cite web | url=http://www.webmd.com/vitamins-and-supplements/nutrition-vitamins-11/fat-water-nutrient | title=Vitamins & Supplements Center – Nutritional, Herbal, Dietary, and More - WebMD}} 6. ^Novella, S: Medical Myths, Lies, and Half-Truths: What We Think We Know May Be Hurting Us, The Great Courses 7. ^{{cite journal |author=Jarvis WT |title=Food faddism, cultism, and quackery |journal=Annu. Rev. Nutr. |volume=3 |pages=35–52 |year=1983 |pmid=6315036 |doi=10.1146/annurev.nu.03.070183.000343}} 8. ^{{cite journal |author = Jukes TH | year =1990 | title = Nutrition Science from Vitamins to Molecular Biology | journal = Annual Review of Nutrition | pmid = 2200458 | volume = 10 | issue = 1 | pages = 1–20 | doi = 10.1146/annurev.nu.10.070190.000245}} A short summary is in the journal's preface. 9. ^{{cite journal | author = Braganza, S.F. |author2=Ozuah, P.O. | year = 2005 | title = Fad Therapies | journal = Pediatrics in Review | volume = 26 | issue = 10 | pages = 371–376 | doi = 10.1542/pir.26-10-371 | pmid = 16199591}} 10. ^{{cite journal |title=NIH State-of-the-Science Conference Statement on Multivitamin/Mineral Supplements and Chronic Disease Prevention |journal=NIH Consens State Sci Statements |volume=23 |issue=2 |pages=1–30 |year=2006 |pmid=17332802 |url=http://consensus.nih.gov/2006/2006MultivitaminMineralSOS028main.htm}} 11. ^{{cite journal |vauthors=Huang HY, Caballero B, Chang S, etal |title=The efficacy and safety of multivitamin and mineral supplement use to prevent cancer and chronic disease in adults: a systematic review for a National Institutes of Health state-of-the-science conference |journal=Ann. Intern. Med. |volume=145 |issue=5 |pages=372–385 |date=2006 |pmid=16880453 |url=http://www.annals.org/cgi/pmidlookup?view=reprint&pmid=16880453 |doi=10.1001/archinte.145.2.372}} 12. ^{{cite journal |vauthors=Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C |title=Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases |journal=Cochrane Database Syst Rev |volume=3 |issue= 3|pages=CD007176 |year=2012 |pmid=22419320 |doi=10.1002/14651858.CD007176.pub2|url=http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-31802015000200164 }} 13. ^{{cite journal | authors = Satia JA, Littman A, Slatore CG, Galanko JA, White E |year = 2009 |title = Long-term Use of {beta}-Carotene, Retinol, Lycopene, and Lutein Supplements and Lung Cancer Risk: Results From the VITamins And Lifestyle (VITAL) Study | journal = American Journal of Epidemiology | volume = 169| issue = 7| pages = 815–828| doi = 10.1093/aje/kwn409 | pmid = 19208726 | pmc=2842198}} 14. ^{{cite journal |vauthors=Neuhouser ML, Wassertheil-Smoller S, Thomson C, etal |title=Multivitamin use and risk of cancer and cardiovascular disease in the Women's Health Initiative cohorts |journal=Arch. Intern. Med. |volume=169 |issue=3 |pages=294–304 |date=2009 |pmid=19204221 |doi=10.1001/archinternmed.2008.540 |url=|pmc=3868488 }} 15. ^{{cite journal |vauthors=Vogelsang A, Shute E, Shute W |title=Some medical uses of vitamin E |journal=Med World (New York) |volume=161 |issue=2 |pages=83–89 |date=1948 |pmid=18911314 |doi= |url=}} 16. ^{{cite journal |last=Jungeblut |first=CW |year=1937 |title=Vitamin C Therapy and Prophylaxis in Experimental Poliomyelitis |journal=The Journal of Experimental Medicine |volume=65 |pages=127–146 |url=http://jem.rupress.org/cgi/content/abstract/65/1/127 |doi=10.1084/jem.65.1.127 |pmid=19870585 |issue=1 |pmc=2133474}} 17. ^{{cite journal|author=Klenner, Fred R. |title=The treatment of poliomyelitis and other virus diseases with vitamin C |journal=Southern Medicine & Surgery |volume=111 |issue=7 |pages=209–214 |date=1949 |pmid=18147027 |doi=}} 18. ^{{cite journal |author=KAUFMAN W |title=Niacinamide therapy for joint mobility; therapeutic reversal of a common clinical manifestation of the normal aging process |journal=Conn State Med J |volume=17 |issue=7 |pages=584–9 |date=July 1953 |pmid=13060032}} 19. ^{{cite journal |vauthors=Altschul R, Hoffer A, Stephen JD |title=Influence of nicotinic acid on serum cholesterol in man |journal=Arch. Biochem. Biophys. |volume=54 |issue=2 |pages=558–559 |date=1955 |pmid=14350806 |doi= 10.1016/0003-9861(55)90070-9|url=}} 20. ^{{cite journal |vauthors=Altschul R, Hoffer A |title=The Effect of Nicotinic Acid on Hypercholesterolæmia |journal=Can Med Assoc J |volume=82 |issue= 15|pages=783–785 |date=1960 |pmid=13792994 |pmc=1938010}} 21. ^{{cite book |author=Williams, Roger Lawrence |title=Biochemical Individuality |publisher=McGraw-Hill |location=New York |year=1998 |pages= |isbn=978-0-87983-893-5 |oclc= |doi= }} 22. ^{{cite book |author=Stone, Irwin |title=The healing factor: "vitamin C" against disease |publisher=Perigee Books |location=New York |year=1982 |pages= |isbn=978-0-399-50764-9}} 23. ^{{cite journal |vauthors=Richardson MA, Sanders T, Palmer JL, Greisinger A, Singletary SE |title=Complementary/alternative medicine use in a comprehensive cancer center and the implications for oncology |journal=J. Clin. Oncol. |volume=18 |issue=13 |pages=2505–2514 |date=2000 |pmid=10893280 |doi= 10.1200/JCO.2000.18.13.2505|url=http://jco.ascopubs.org/cgi/content/full/18/13/2505}} 24. ^{{cite journal |vauthors=Lin J, Cook NR, Albert C, et al |title=Vitamins C and E and Beta Carotene Supplementation and Cancer Risk: A Randomized Controlled Trial |journal=J. Natl. Cancer Inst. |volume=101 |issue=1 |pages=14–23 |date=2009 |pmid=19116389 |doi=10.1093/jnci/djn438 |url= |pmc=2615459}} 25. ^{{cite journal | vauthors = Cameron E, Pauling L | title = Supplemental ascorbate in the supportive treatment of cancer: Prolongation of survival times in terminal human cancer | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 73 | issue = 10 | pages = 3685–9 | date = October 1976 | pmid = 1068480 | pmc = 431183 | doi = 10.1073/pnas.73.10.3685| bibcode = 1976PNAS...73.3685C }} 26. ^{{cite journal |vauthors=Juraschek SP, Miller ER, Gelber AC |title=Effect of oral vitamin C supplementation on serum uric acid: a meta-analysis of randomized controlled trials |journal=Arthritis Care Res (Hoboken) |volume=63 |issue=9 |pages=1295–306 |date=September 2011 |pmid=21671418 |pmc=3169708 |doi=10.1002/acr.20519 |url=}} 27. ^{{cite journal |last=Choi |first=Hyon K. |author2=Xiang Gao |author3=Gary Curhan |date=2009|title=Vitamin C Intake and the Risk of Gout in Men – A Prospective Study|journal=Archives of Internal Medicine |volume= 169 |issue= 5|pages=502–507|url=http://archinte.ama-assn.org/cgi/content/abstract/169/5/502 |doi=10.1001/archinternmed.2008.606|pmid=19273781|pmc=2767211}} 28. ^{{Cite journal|last=Hemilä|first=Harri|last2=Chalker|first2=Elizabeth|date=2013-01-31|title=Vitamin C for preventing and treating the common cold|url=|journal=The Cochrane Database of Systematic Reviews|volume=|issue=1|pages=CD000980|doi=10.1002/14651858.CD000980.pub4|issn=1469-493X|pmid=23440782|pmc=1160577|via=}} 29. ^{{Cite journal | last1 = Cabanillas | first1 = F | title = Vitamin C and cancer: what can we conclude--1,609 patients and 33 years later? | journal = Puerto Rico Health Sciences Journal |volume = 29 |issue = 3 |pages = 215–217 |year = 2010 |pmid = 20799507}} 30. ^{{cite book | last1 = Institute of Medicine | title = Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids | chapter = Vitamin E | publisher = The National Academies Press | year = 2000 | location = Washington, DC | pages = 186–283 | chapter-url = https://www.nap.edu/read/9810/chapter/8}} 31. ^{{cite journal |vauthors=Kim HJ, Giovannucci E, Rosner B, Willett WC, Cho E |title=Longitudinal and secular trends in dietary supplement use: Nurses' Health Study and Health Professionals Follow-Up Study, 1986-2006 |journal=J Acad Nutr Diet |volume=114 |issue=3 |pages=436–443 |date=2014 |pmid=24119503 |pmc=3944223 |doi=10.1016/j.jand.2013.07.039 |url=}} 32. ^{{cite journal|last1=Eidelman |first1=RS|last2=Hollar |first2=D|last3=Hebert|first3=PR|last4=Lamas|first4=GA| last5=Hennekens|first5=CH|title=Randomized trials of vitamin E in the treatment and prevention of cardiovascular disease|journal= Archives of Internal Medicine|date=2004|pmid=15277288| doi=10.1001/archinte.164.14.1552|volume=164|issue=14|pages=1552–1556}} 33. ^{{cite journal |vauthors=Miller ER, Pastor-Barriuso R, Dalal D, Riemersma RA, Appel LJ, Guallar E |title=Meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality |journal=Ann. Intern. Med. |volume=142 |issue=1 |pages=37–46 |date=2005 |pmid=15537682 |doi= 10.7326/0003-4819-142-1-200501040-00110|url=}} 34. ^[https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=ce739d68-d89c-437c-90fb-3c0c45140f22 Niacin tablet label] Updated March 14, 2013. Page accessed Feb 11, 2016 35. ^{{cite journal | vauthors = Keene D, Price C, Shun-Shin MJ, Francis DP | title = Effect on cardiovascular risk of high density lipoprotein targeted drug treatments niacin, fibrates, and CETP inhibitors: meta-analysis of randomised controlled trials including 117,411 patients | journal = BMJ | volume = 349 | pages = g4379 | date = July 2014 | pmid = 25038074 | pmc = 4103514 | doi = 10.1136/bmj.g4379 }} 36. ^{{cite journal | vauthors = Schandelmaier S, Briel M, Saccilotto R, Olu KK, Arpagaus A, Hemkens LG, Nordmann AJ | title = Niacin for primary and secondary prevention of cardiovascular events | journal = The Cochrane Database of Systematic Reviews | volume = 6 | pages = CD009744 | date = June 2017 | pmid = 28616955 | doi = 10.1002/14651858.CD009744.pub2 }} 37. ^{{cite journal | vauthors = Garg A, Sharma A, Krishnamoorthy P, Garg J, Virmani D, Sharma T, Stefanini G, Kostis JB, Mukherjee D, Sikorskaya E | title = Role of Niacin in Current Clinical Practice: A Systematic Review | journal = The American Journal of Medicine | volume = 130 | issue = 2 | pages = 173–187 | date =2017 | pmid = 27793642 | doi = 10.1016/j.amjmed.2016.07.038 }} External links
4 : Orthomolecular medicine|Vitamins|Medical treatments|Therapy |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。