{"id":1899,"date":"2019-10-26T01:02:11","date_gmt":"2019-10-26T01:02:11","guid":{"rendered":"https:\/\/drmirkin.com\/?p=1899"},"modified":"2019-10-26T01:02:12","modified_gmt":"2019-10-26T01:02:12","slug":"high-doses-of-water-soluble-vitamins-may-be-harmful","status":"publish","type":"post","link":"http:\/\/drmirkin.com\/?p=1899","title":{"rendered":"High Doses of Water-Soluble Vitamins May Be Harmful"},"content":{"rendered":"\n

Taking large\ndoses of vitamins B6 and B12 for an average 20 years is associated with\nincreased risk of hip fractures (JAMA Netw Open<\/em>, May 3,\n2019;2(5):e193591). It is well-known that taking large doses of the fat-soluble\nvitamins — A, D, E and K — can harm you (Ann Intern Med<\/em>, 2005;142(1):37-46).\nLarge doses of vitamin D have been shown to increase risk for bone fractures (JAMA<\/em>,\n2010;303(18):1815-1822), and large doses of vitamin A are associated with\nincreased risk for lung cancer in smokers (Int J Cancer<\/em>, 2010;127(1):172-184).\nYou may also be harmed by large doses of the water-soluble B vitamins (folate,\nthiamine, riboflavin, niacin, pantothenic acid, biotin, vitamin B6 and vitamin\nB12) or vitamin C (Int J Cancer<\/em>, 2010;127(1):172-184).<\/p>\n\n\n\n

The\nwater-soluble vitamins have been felt to be safe because excessive dosages can\npass out in your urine. Doctors used to prescribe large doses of the water-soluble\nvitamins, pyridoxine (B6), niacin (B3), and cobalamin (B12), to lower high\nblood levels of homocysteine that are associated with increased risk for heart\nattacks (Nutr J<\/em>, Jan 10, 2015;14:6) and certain cancers (Radiol\nOncol<\/em>, 2010 Jun; 44(2): 79-85). They don’t do that anymore because\neven though taking B vitamins lowers homocysteine blood levels, it has\nrepeatedly failed to reduce the rate of heart attacks (PLoS One<\/em>,\n2014;9(9):e107060; JAMA<\/em>, Apr 28, 2010;303(16):1603-9) or\ncancers (Arch Intern Med<\/em>, 2010;170(18):1622-1631). High levels of\nhomocysteine weaken bones (Clin Chem Lab Med<\/em>,\n2007;45(12):1621-1632), but lowering homocysteine blood levels with vitamins\nB3, B6, and B12 does not prevent bone fractures (JBMR Plus<\/em>,\n2018;2(5):295-303). Instead, it increases bone fracture risk (Am J Clin\nNutr<\/em>, 2014;100(6):1578-1586; J Bone Miner Res,<\/em>\n2017;32(10):1981-1989). <\/p>\n\n\n\n

How Most Vitamins Work<\/strong>
\nBefore your body can use the food that you eat, your body must convert the food\ninto the chemicals that provide you with energy and build all the structures in\nyour body. The water-soluble B vitamins are parts of enzymes that start\nchemical reactions that provide you with these substances. The B vitamins cause\nChemical A to be converted to chemical B plus other chemicals C, D, E, and so\nforth. When you eat the vitamins in food, other enzymes that we may not even\nknow about in the food break down the remaining chemicals so they do not\naccumulate in your body to possibly harm you. However, when you take vitamins\nin a pill, you may not get all the other enzymes that you would have gotten in\nfood to prevent you from accumulating harmful products in your body. For a more\ndetailed explanation of how homocysteine is affected by the B vitamins, see Do You\nNeed Vitamin Pills?<\/a> <\/p>\n\n\n\n

Other\npossible explanations for increased risk for bone fractures from high doses of\nthe B vitamins:
\n\u2022 They may interfere with nerve conduction to increase risk for falling and\nbreaking bones (Acta Neurol Scand<\/em>, 1987;76(1):8-11).
\n\u2022 They may block the bone-protecting effects of the female hormone estrogen (J Biol\nChem<\/em>, 1992;267(6):3819-3824).
\n\u2022 They may contain an inactive form of B6 that blocks the active form of B6 (Toxicol\nIn Vitro<\/em>, 2017;44:206-212).<\/p>\n\n\n\n

My Recommendations<\/strong>
\nI believe that you should not take vitamin pills in excess of your daily\nrequirements unless you have a proven deficiency of a vitamin, as evidenced by\nlow blood levels of that vitamin or a specific condition that requires large\ndoses of that vitamin.<\/p>\n","protected":false},"excerpt":{"rendered":"

It is well-known that taking large doses of the fat-soluble vitamins — A, D, E and K — can harm you. You may also be harmed by large doses of the water-soluble B vitamins or vitamin C.<\/p>\n","protected":false},"author":1,"featured_media":1024,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[16],"tags":[111,110,112],"class_list":["post-1899","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-nutrition","tag-b-vitamins","tag-vitamins","tag-water-soluble-vitamins"],"_links":{"self":[{"href":"http:\/\/drmirkin.com\/index.php?rest_route=\/wp\/v2\/posts\/1899","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/drmirkin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/drmirkin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/drmirkin.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/drmirkin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1899"}],"version-history":[{"count":0,"href":"http:\/\/drmirkin.com\/index.php?rest_route=\/wp\/v2\/posts\/1899\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/drmirkin.com\/index.php?rest_route=\/wp\/v2\/media\/1024"}],"wp:attachment":[{"href":"http:\/\/drmirkin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1899"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/drmirkin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1899"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/drmirkin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1899"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}