Vegan nutrition

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Healthy vegan meal composition shown using the food plate method

Vegan nutrition refers to the nutritional and human health aspects of vegan diets. A well-planned, balanced vegan diet is suitable to meet all recommendations for nutrients in every stage of human life.[1] Vegan diets tend to be higher in dietary fiber, magnesium, folic acid, vitamin C, vitamin E, iron, and phytochemicals; and lower in calories, saturated fat, cholesterol, long-chain omega-3 fatty acids, vitamin D, calcium, zinc, and vitamin B12.[2]

Researchers agree that those on a vegan diet should take a vitamin B12 dietary supplement.[1][3]

Positions of dietetic and government associations[edit]

The American Academy of Nutrition and Dietetics and Dietitians of Canada state that properly planned vegan diets are appropriate for all life stages, including pregnancy, lactation, infancy, childhood, and adolescence.[4][5] They indicate that vegetarian diets may be more common among adolescents with eating disorders, but that its adoption may serve to camouflage a disorder rather than cause one. The Australian National Health and Medical Research Council similarly recognizes a well-planned vegan diet as viable for any age,[6][7] as does the New Zealand Ministry of Health,[8] British National Health Service,[9] British Nutrition Foundation,[10] Dietitians Association of Australia,[11] United States Department of Agriculture,[12] Mayo Clinic,[13] Canadian Pediatric Society,[14] and Heart and Stroke Foundation of Canada.[15] The British National Health Service's Eatwell Plate allows for an entirely plant-based diet,[16] as does the United States Department of Agriculture's (USDA) MyPlate.[17][18] The USDA allows tofu to replace meat in the National School Lunch Program.[19] The American Academy of Nutrition and Dietetics adds that well-planned vegan diets are also appropriate for older adults and athletes.[1]

The German Society for Nutrition does not recommend a vegan diet for babies, children and adolescents, or for pregnancy or breastfeeding, citing insufficient data for these subpopulations.[20]

Pregnancy, infants and children[edit]

The Academy of Nutrition and Dietetics and Dietitians of Canada consider well-planned vegetarian and vegan diets "appropriate for individuals during all stages of the lifecycle, including pregnancy, lactation, infancy, childhood, and adolescence, and for athletes". The German Society for Nutrition cautioned against a vegan diet for babies, children, and adolescents, and during pregnancy and breastfeeding, due to insufficient data.[21][20] The position of the Canadian Pediatric Society is that "well-planned vegetarian and vegan diets with appropriate attention to specific nutrient components can provide a healthy alternative lifestyle at all stages of fetal, infant, child and adolescent growth. It is recommended that attention should be given to nutrient intake, particularly protein, vitamins B12 and D, essential fatty acids, iron, zinc, and calcium.[14]

According to a 2015 systematic review, there was little evidence available about vegetarian and vegan diets during pregnancy, and a lack of randomized studies meant that the effects of diet could not be distinguished from confounding factors.[22] It concluded: "Within these limits, vegan-vegetarian diets may be considered safe in pregnancy, provided that attention is paid to vitamin and trace element requirements."[22] A daily source of vitamin B12 is important for pregnant and lactating vegans, as is vitamin D if there are concerns about low sun exposure.[23] A different review found that pregnant vegetarians consumed less zinc than pregnant non-vegetarians, with both groups' intake below recommended levels; however, the review found no significant difference between groups in actual zinc levels in bodily tissues, nor any effect on gestation period or birth weight.[24]

Researchers have reported cases of vitamin B12 deficiency in lactating vegetarian mothers that were linked to deficiencies and neurological disorders in their children.[25][26] It is recommended that a doctor or registered dietitian should be consulted about taking supplements during pregnancy.[27][28]

Vegan diets have attracted negative attention from the media because of cases of nutritional deficiencies that have come to the attention of the courts, including the death of a baby in New Zealand in 2002 due to hypocobalaminemia, i.e. vitamin B12 deficiency.[29][30]

Critical nutrients[edit]

The American Academy of Nutrition and Dietetics states that special attention may be necessary to ensure that a vegan diet will provide adequate amounts of vitamin B12, omega-3 fatty acids, vitamin D, calcium, iodine, iron, and zinc.[1] These nutrients are available in plant foods, with the exception of vitamin B12, which can be obtained only from B12-fortified vegan foods or supplements.[31] Iodine may also require supplementation, such as using iodized salt.[1]

Vitamin B12[edit]

Vegan food pyramid based on suggestions from the American Dietetic Association

Vitamin B12 is not made by plants or animals, but by bacteria that grow in soil, feces, dirty water, the intestines of animals or laboratories,[32][33][34][35][36] so plant foods are not reliable sources of B12.[37] It is synthesized by some gut bacteria in humans and other animals, but humans cannot absorb the B12 made in their guts, as it is made in the colon which is too far from the small intestine, where absorption of B12 occurs.[38] Ruminants, such as cows and sheep, absorb B12 produced by bacteria in their guts.[38]

Animals store vitamin B12 in liver and muscle and some pass the vitamin into their eggs and milk; meat, liver, eggs and milk are therefore sources of B12.[39][40]

The UK Vegan Society, the Vegetarian Resource Group, and the Physicians Committee for Responsible Medicine, among others, recommend that every vegan consume adequate B12 either from fortified foods or by taking a supplement.[41][42][43][44]

Vitamin B12 deficiency is potentially extremely serious, leading to megaloblastic anemia (an undersupply of oxygen due to malformed red blood cells),[45] nerve degeneration and irreversible neurological damage.[46] Cases of severe vitamin B12 deficiency have been reported in vegan adults, children[47] infants and toddlers.[48]

Because B12 is stored in large amounts in the liver, deficiency in adults may begin only years after adoption of a diet lacking B12. For infants and young children who have not built up these stores, onset of B12 deficiency can be faster and supplementation for vegan children is thus crucial.

Evidence shows that vegans who are not taking vitamin B12 supplements do not consume sufficient B12 and often have abnormally low blood concentrations of vitamin B12.[49] This is because, unless fortified, plant foods do not contain reliable amounts of active vitamin B12. Vegans are advised to adopt one of the following dietary options:[50]

  • Consume fortified foods 2-3 times per day to get at least 3 micrograms of vitamin B12,
  • or take at least 10 micrograms of B12 as a supplement once per day
  • or take at least 2000 micrograms of B12 as a supplement once per week

B12 is more efficiently absorbed in small regular doses, which explains why the quantity required rises so quickly as frequency goes down.

The US National Institutes of Health recommends B12 intake in a range from 0.4 micrograms a day for infants, to 2.4 micrograms for adults, and up to 2.8 micrograms for nursing mothers. [51] The European Food Safety Authority set the Adequate Intake at 1.5 micrograms for infants, 4 micrograms for children and adults, and 4.5 and 5 micrograms during pregnancy and nursing.[52] These amounts can be obtained by eating B12 fortified foods, which include some common breakfast cereals, plant milks, and meat analogues, as well as from common multivitamins such as One-A-Day. Some of the fortified foods require only a single serving to provide the recommended B12 amounts. [53]

It has been suggested that nori (an edible seaweed), tempeh (a fermented soybean food), and nutritional yeast may be sources of vitamin B12.[54][55] In 2016, the Academy of Nutrition and Dietetics stated that nori, fermented foods (such as tempeh), spirulina, chlorella algae, and unfortified nutritional yeast are not adequate sources of vitamin B12 and that vegans need to consume regularly fortified foods or supplements containing B12. Otherwise, vitamin B12 deficiency may develop, as has been demonstrated in case studies of vegan infants, children, and adults.[56]

Vitamin B12 is mostly manufactured by industrial fermentation of various kinds of bacteria, which make forms of cyanocobalamin, which are further processed to generate the ingredient included in supplements and fortified foods.[57][58] A Pseudomonas denitrificans strain was most commonly used as of 2017.[59][60] It is grown in a medium containing sucrose, yeast extract, and several metallic salts. To increase vitamin production, it is supplemented with sugar beet molasses, or, less frequently, with choline.[59] Certain brands of B12 supplements are certified vegan.[61]

Iodine[edit]

Humans require iodine for the production of thyroid hormones that enable normal thyroid function.[62] Iodine supplementation may be necessary for vegans in countries where salt is not typically iodized, where it is iodized at low levels, or where, as in Britain and Ireland, dairy products are relied upon for iodine delivery because of low levels in the soil.[63] Iodine can be obtained from most vegan multivitamins or regular consumption of seaweeds, such as kelp.[64]

One study reported a "potential danger of iodine deficiency disorders due to strict forms of vegetarian nutrition, especially when fruits and vegetables grown in soils with low [iodine] levels are ingested."[65] A study in Germany showed that iodine status of vegans is a concern.[66]

Vegan diets typically require special attention for iodine, for which the only substantial and reliable vegan sources are sea vegetables, iodized salt and supplements. The iodine content of sea vegetables varies widely and may provide more than the recommended upper limit of iodine intake.[1]

Protein[edit]

Proteins are composed of amino acids. Vegans obtain all their protein from plants, omnivores usually a third, and ovo-lacto vegetarians half.[67] Sources of plant protein include legumes such as soy beans (consumed as tofu, tempeh, textured vegetable protein, soy milk, and edamame), peas, peanuts, black beans, and chickpeas (the latter often eaten as hummus); grains such as quinoa, brown rice, corn, barley, bulgur, and wheat (the latter eaten as bread and seitan); and nuts and seeds. Combinations that contain high amounts of all the essential amino acids include rice and beans, corn and beans, and hummus and whole-wheat pita.[68] In 2012, the United States Department of Agriculture stated that soy protein (tofu) may replace meat protein in the National School Lunch Program.[19]

The Academy of Nutrition and Dietetics said in 2009 that a variety of plant foods consumed over the course of a day can provide all the essential amino acids for healthy adults, which means that protein combining in the same meal is generally not necessary.[69] The Dietitian's Guide to Vegetarian Diets writes that there is little reason to advise vegans to increase their protein intake; but erring on the side of caution, the authors recommend a 25 percent increase over the RDA for adults, to 1 g/kg (15gr/lb) of body weight.[70]

Omega-3 fatty acids[edit]

Flaxseeds are a rich source of ALA, the precursor to DHA and EPA, the omega-3 fatty acids
Walnuts are another rich source of ALA, the precursor to DHA and EPA, the omega-3 oils

Experts have not established recommended amounts for omega-3 fatty acids, except for ALA.[71] The human body can use ALA to synthesize DHA and EPA. However, this only works efficiently if the ratio between omega 3 (mainly in flaxseed, chia seeds) to omega 6 (mainly in sunflower oil) does not exceed 1:5.[72] This can sometimes be hard to accomplish as modern food includes a lot of omega 6.[73]

Major vegan sources of the essential omega-3 fatty acid ALA include walnuts, flaxseeds and flaxseed oil, canola (rapeseed) oil, algae oil, hempseeds and hempseed oil, olive oil, and avocado.[1]

While there is little evidence of adverse health or cognitive effects due to DHA deficiency in adult vegetarians or vegans, fetal and breast milk levels remain a concern.[74]

DHA supplements derived from DHA-rich microalgae are available, and the human body can also convert DHA to EPA.[75]

Calcium[edit]

It is recommended that vegans eat three servings per day of a high-calcium food, such as fortified plant milks, green leafy vegetables, seeds, tofu, or other calcium-rich foods, and take a calcium supplement as necessary.[1][76]

A 2009 study of bone density found the bone density of vegans was 94 percent that of omnivores, but deemed the difference clinically insignificant.[77]

Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest that people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake (RDI) for calcium in adults.[78][79][80]

Calcium intake through food sources is preferred over supplementation given inconclusive but growing evidence to suggest that supplementation carries no health benefit or might be harmful[81].[82]

Iron[edit]

photograph of food in caption
Granola oatmeal with soy milk. Oats are good source of iron that also contain good amounts of plant protein, fiber, magnesium, zinc and folate.[83]

It is recommended for vegans to eat iron-rich foods and vitamin C daily.[84] In several studies, vegans were not found to suffer from iron-deficiency any more than non-vegans.[85][86][87][88] However, due to the low absorption rate on non-heme iron it is recommended to eat dark leafy greens (and other sources of iron) together with sources of Vitamin C.[89] Iron supplementation should be taken at different times to other supplements with a 2+ valence (chemistry) such as calcium or magnesium, as they inhibit the absorption of iron.[90]

Iron and the zinc levels of vegans may be of concern because of the limited bioavailability of these minerals. There are concerns about the bioavailability of iron from plant foods, assumed by some researchers to be 5–15 percent compared to 18 percent from a non-vegetarian diet.[91] Iron-deficiency anemia is found as often in non-vegetarians as in vegetarians, and vegetarians' iron stores are lower.[92]

Due to the lower bioavailability of iron from plant sources, the Food and Nutrition Board of the National Academy of Sciences established a separate RDA for vegetarians and vegans of 14 mg for vegetarian men and postmenopausal women, and 33 mg for premenopausal women not using oral contraceptives.[93]

High-iron vegan foods include soybeans, blackstrap molasses, black beans, lentils, chickpeas, spinach, tempeh, tofu, and lima beans.[94][95] Iron absorption can be enhanced by eating a source of vitamin C at the same time,[96] such as half a cup of cauliflower or five fluid ounces of orange juice. Coffee and some herbal teas can inhibit iron absorption, as can spices that contain tannins such as turmeric, coriander, chiles, and tamarind.[95]

Vitamin D[edit]

The main function of vitamin D in the body is to enhance absorption of calcium for normal mineralization of bones and calcium-dependent tissues.[23]

Sunlight, fortified foods, and dietary supplements are the main sources of vitamin D for vegans. Humans produce vitamin D naturally in response to sun exposure and ultraviolet light (UV) acting on skin to stimulate vitamin D synthesis.[23] UV light penetrates the skin at wavelengths between 290 and 320 nanometers, where it is then converted into vitamin D3.[23] Vitamin D2 can be obtained from fungi, such as mushrooms exposed to sun or industrial ultraviolet light, offering a vegan choice for dietary or supplemental vitamin D.[97][98] Plant milks, such as from oat, soy, or almond, and breakfast cereals are commonly fortified with vitamin D.[23]

The recommended daily intake of vitamin D for adults is 600 IU (15 micrograms), and for adults over 70 years old, 800 IU (20 micrograms).[23]

Vitamin D comes in two forms. Cholecalciferol (vitamin D3) is synthesized in the skin after exposure to the sun or consumed from food, usually from animal sources.[23] Ergocalciferol (vitamin D2) is derived from ergosterol from UV-exposed mushrooms or yeast.[23] When produced industrially as supplements, vitamin D3 is typically derived from lanolin in sheep wool. However, both provitamins and vitamins D2 and D3 have been discovered in various species of edible Cladina lichens (especially Cladina rangiferina).[99] These edible lichen are harvested in the wild for producing vegan vitamin D3.[100] Conflicting studies have suggested that the two forms of vitamin D may or may not be bioequivalent.[101] According to 2011 research from the U. S. National Academy of Medicine (then called Institute of Medicine), the differences between vitamins D2 and D3 do not affect metabolism, both function as prohormones, and when activated, exhibit identical responses in the body.[102] Although vitamin D3 is produced in small amounts by lichens or algae exposed to sunlight,[103][104] industrial production in commercial quantities is limited, and there are few supplement products as of 2019.[105]

Choline[edit]

Some news reports presented vegan diets as deficient in choline following an opinion piece in the BMJ by a nutritionist affiliated with the meat industry.[106][107][108][109] Although many animal products, like liver and egg, contain high amounts of choline (355 mg/3 oz and 126 mg/large egg, respectively), wheat germ (172 mg/cup), Brussels sprouts (63 mg/cup), and broccoli (62 mg/cup) are also good sources of choline.[110] Other sources are, among others, soybeans, mushrooms, tangerines and whole wheat pitta bread.[107]

Due to lack of evidence, no country has published a Recommended Dietary Allowance (RDA) for choline, which is a vitamin-like essential nutrient. The Australian, New Zealand, and European Union national nutrition bodies note there have been no reports of choline deficiency in the general population.[111] There are, however, Adequate Intakes such as the European Union's number of 400 mg/day for adults, and the US's number of 425 mg/day for adult non-pregnant women and 550 mg/day for adult men. An Adequate Intake is a level assumed to ensure nutritional adequacy, established when evidence is insufficient to develop an RDA[112] (see Dietary Reference Intake).

See also[edit]

References[edit]

  1. ^ a b c d e f g h Melina, Vesanto; Craig, Winston; Levin, Susan (1 May 2015). "Position of the Academy of Nutrition and Dietetics: Vegetarian Diets" (PDF). Journal of the Academy of Nutrition and Dietetics. 115 (5): 1970–1980. doi:10.1016/j.jand.2016.09.025. ISSN 2212-2672. PMID 27886704. Retrieved 26 January 2019.
  2. ^ Craig, Winston J (May 2009). "Health effects of vegan diets". The American Journal of Clinical Nutrition. 89 (5): 1627S–1633S. doi:10.3945/ajcn.2009.26736N. PMID 19279075. Vegan diets are usually higher in dietary fiber, magnesium, folic acid, vitamins C and E, iron, and phytochemicals, and they tend to be lower in calories, saturated fat and cholesterol, long-chain n–3 (omega-3) fatty acids, vitamin D, calcium, zinc, and vitamin B-12. ... A vegan diet appears to be useful for increasing the intake of protective nutrients and phytochemicals and for minimizing the intake of dietary factors implicated in several chronic diseases.
  3. ^ Mangels, Reed; Messina, Virginia; and Messina, Mark. "Vitamin B12 (Cobalamin)," The Dietitian's Guide to Vegetarian Diets. Jones & Bartlett Learning, 2011, pp. 181–192.
    • Mangels, Reed. "Vitamin B12 in the Vegan Diet", Vegetarian Resource Group, accessed December 17, 2012: "Vitamin B12 is needed for cell division and blood formation. Neither plants nor animals make vitamin B12. Bacteria are responsible for producing vitamin B12. Animals get their vitamin B12 from eating foods contaminated with vitamin B12 and then the animal becomes a source of vitamin B12. Plant foods do not contain vitamin B12 except when they are contaminated by microorganisms or have vitamin B12 added to them. Thus, vegans need to look to fortified foods or supplements to get vitamin B12 in their diet."
    • "Vitamin B12", Office of Dietary Supplements, National Institutes of Health, accessed December 17, 2012.
    • Norris, Jack. "Vitamin B12: Are you getting it?", Vegan Outreach, July 26, 2006: "Contrary to the many rumors, there are no reliable, unfortified plant sources of vitamin B12 ... [There is an] overwhelming consensus in the mainstream nutrition community, as well as among vegan health professionals, that vitamin B12 fortified foods or supplements are necessary for the optimal health of vegans, and even vegetarians in many cases. Luckily, vitamin B12 is made by bacteria such that it does not need to be obtained from animal products."
  4. ^ Melina, Vesanto; Craig, Winston; Levin, Susan (December 2016). "Position of the Academy of Nutrition and Dietetics: Vegetarian Diets". Journal of the Academy of Nutrition and Dietetics. 116 (12): 1970–1980. doi:10.1016/j.jand.2016.09.025. ISSN 2212-2672. PMID 27886704.
  5. ^ American Dietetic Association (2003). "Position of the American Dietetic Association and Dietitians of Canada: Vegetarian diets". Journal of the American Dietetic Association. 103 (6): 748–765. CiteSeerX 10.1.1.739.2592. doi:10.1053/jada.2003.50142. PMID 12778049.
  6. ^ "Government recognises vegan diet as viable option for all Australians" (Press release). Vegan Australia. 12 July 2013. Archived from the original on 22 September 2013 – via News International.
  7. ^ "Dietary Guidelines for Australia" (PDF). Australian National Health and Medical Research Council. Archived from the original (PDF) on 12 January 2016. Retrieved 21 September 2013.
  8. ^ "Eating for Healthy Vegetarians" (PDF). The New Zealand Ministry of Health. Archived from the original (PDF) on 24 January 2019.
  9. ^ "The vegan diet". The British National Health Service. 3 September 2018. Archived from the original on 19 May 2019.
  10. ^ "Vegetarian nutrition". The British Nutrition Foundation. Archived from the original on 28 April 2019.
  11. ^ "Vegan diets: everything you need to know". The Dietitians Association of Australia. Archived from the original on 19 May 2019.
  12. ^ "Tips for Vegetarians". The United States Department of Agriculture. 22 June 2015. Archived from the original on 23 March 2019.
  13. ^ "Vegetarian diet: How to get the best nutrition". The Mayo Clinic. Archived from the original on 19 May 2019.
  14. ^ a b Amit, M (May 2010). "Vegetarian diets in children and adolescents". Paediatrics & Child Health. 15 (5): 303–14. PMC 2912628. PMID 21532796.
  15. ^ "For vegetarians". The Heart and Stroke Foundation of Canada. Archived from the original on 28 April 2019.
  16. ^ "The eatwell plate", National Health Service; "The vegan diet", National Health Service.
  17. ^ "What Foods Are in the Protein Foods Group?". United States Department of Agriculture. 23 February 2015. Archived from the original on 16 January 2013. Retrieved 17 January 2013.
  18. ^ "Vegetarian Choices in the Protein Foods Group". United States Department of Agriculture. Archived from the original on 18 October 2014. Retrieved 13 October 2014.
  19. ^ a b Long, Cynthia (22 February 2012). "Crediting Tofu and Soy Yogurt Products" (PDF). Food and Nutrition Service (Memorandum). Alexandria, VA: United States Department of Agriculture. Archived from the original (PDF) on 12 July 2017. Retrieved 13 March 2018. The Nutrition Standards in the National School Lunch and School Breakfast Programs final rule was published on January 26, 2012. The final rule gives schools the option to offer commercially prepared tofu as a meat alternate in the National School Lunch Program (NSLP) and School Breakfast Program (SBP).
  20. ^ a b Richter, Margrit; Kroke, Anja; Grünewald-Funk, Dorle; Heseker, Helmut; Virmani, Kiran; Watzl, Bernhard (September 2020). "Update to the position of the German Nutrition Society on vegan diets in population groups with special nutritional requirements". Ernährungs Umschau. Deutsche Gesellschaft für Ernährung e. V. (DGE). doi:10.4455/eu.2020.044 (inactive 31 October 2021). Retrieved 2021-04-04. Because the available data remain insufficient, no satisfactory assessment can be made with regard to micronutrient intake and supply status or prevalence of nutrient deficiencies or other adverse health effects regarding a vegan diet in these special population groups.CS1 maint: DOI inactive as of October 2021 (link)
  21. ^ Richter M, Boeing H, Grünewald-Funk D, Heseker H, Kroke A, Leschik-Bonnet E, Oberritter H, Strohm D, Watzl B for the German Nutrition Society (DGE) (12 April 2016). "Vegan diet. Position of the German Nutrition Society (DGE)" (PDF). Ernahrungs Umschau. 63 (4): 92–102. Erratum in: 63(05): M262. doi:10.4455/eu.2016.021.CS1 maint: uses authors parameter (link)
  22. ^ a b Piccoli, GB; Clari, R; Vigotti, FN; Leone, F; Attini, R; Cabiddu, G; Mauro, G; Castelluccia, N; Colombi, N; Capizzi, I; Pani, A; Todros, T; Avagnina, P (April 2015). "Vegan-vegetarian diets in pregnancy: danger or panacea? A systematic narrative review". BJOG. 122 (5): 623–633. doi:10.1111/1471-0528.13280. hdl:2318/1523463. PMID 25600902. S2CID 206906653.
  23. ^ a b c d e f g h "Vitamin D". Office of Dietary Supplements, US National Institutes of Health. 26 March 2021. Retrieved 3 April 2021.
  24. ^ Foster, Meika; Herulah, Ursula; Prasad, Ashlini; Petocz, Peter; Samman, Samir (5 June 2015). "Zinc Status of Vegetarians during Pregnancy: A Systematic Review of Observational Studies and Meta-Analysis of Zinc Intake". Nutrients. 7 (6): 4512–4525. doi:10.3390/nu7064512. PMC 4488799. PMID 26056918.
  25. ^ Pepper, M. Reese; Black, Maureen M. (August 2011). "B12 in fetal development". Seminars in Cell & Developmental Biology. 22 (6): 619–623. doi:10.1016/j.semcdb.2011.05.005. PMID 21664980.
  26. ^ Mangels, Ann Reed; Messina, Virginia (June 2001). "Considerations in planning vegan diets". Journal of the American Dietetic Association. 101 (6): 670–677. doi:10.1016/S0002-8223(01)00169-9. PMID 11424546.
  27. ^ "Vitamins, supplements and nutrition in pregnancy", National Health Service, UK.
  28. ^ Schweitzer, Amy (2006). "Dietary Supplements During Pregnancy". The Journal of Perinatal Education. 15 (4): 44–45. doi:10.1624/105812406X107834. PMC 1804304. PMID 17768435.
  29. ^ Di Genova, Tanya; Guyda, Harvey (March 2007). "Infants and children consuming atypical diets: Vegetarianism and macrobiotics". Paediatrics & Child Health. 12 (3): 185–188. doi:10.1093/pch/12.3.185. PMC 2528709. PMID 19030357.
  30. ^ "Religious couple jailed for 5 years for son's manslaughter". NZ Herald. Retrieved 6 January 2021. Caleb died in March last year from broncho-pneumonia associated with anaemia and brain damage caused by vitamin B12 deficiency.
  31. ^ "Vegetarian, vegan and plant-based diet". British Dietetic Association. Retrieved 2021-05-09.
  32. ^ Fang H, Kang J, Zhang D (January 2017). "Microbial production of vitamin 12: a review and future perspectives". Microbial Cell Factories. 16 (1): 15. doi:10.1186/s12934-017-0631-y. PMC 5282855. PMID 28137297.
  33. ^ Moore SJ, Warren MJ (June 2012). "The anaerobic biosynthesis of vitamin B1212". Biochemical Society Transactions. 40 (3): 581–6. doi:10.1042/BST20120066. PMID 22616870.
  34. ^ Graham RM, Deery E, Warren MJ (2009). "18: Vitamin B12: Biosynthesis of the Corrin Ring". In Warren MJ, Smith AG (eds.). Tetrapyrroles Birth, Life and Death. New York, NY: Springer-Verlag. p. 286. doi:10.1007/978-0-387-78518-9_18. ISBN 978-0-387-78518-9.
  35. ^ Rooke J (October 30, 2013). "Do carnivores need Vitamin B12 supplements?". Baltimore Post Examiner.
  36. ^ "Vitamin B12". DSM. Retrieved January 17, 2017.
  37. ^ "Dietary Supplement Fact Sheet: Vitamin B12". National Institutes of Health: Office of Dietary Supplements. Retrieved 2018-02-02. Strict vegetarians and vegans are at greater risk than lacto-ovo vegetarians and nonvegetarians of developing vitamin B12 deficiency because natural food sources of vitamin B12 are limited to animal foods.
  38. ^ a b Gille, D; Schmid, A (February 2015). "Vitamin B12 in meat and dairy products". Nutrition Reviews (Review). 73 (2): 106–15. doi:10.1093/nutrit/nuu011. PMID 26024497.
  39. ^ "Foods highest in Vitamin B12 (based on levels per 100-gram serving)". Nutrition Data, Conde Nast, USDA National Nutrient Database, release SR-21. 2014. Retrieved 16 February 2017.
  40. ^ "Dietary Supplement Fact Sheet: Vitamin B12". Office of Dietary Supplements, National Institutes of Health. Retrieved 28 September 2011.
  41. ^ Watanabe, F. (2007). "Vitamin B12 sources and bioavailability". Experimental Biology and Medicine. 232 (10): 1266–1274. doi:10.3181/0703-MR-67. PMID 17959839. S2CID 14732788.
  42. ^ Walsh, Stephen. "Vegan Society B12 factsheet". Vegan Society. Archived from the original on May 26, 2008. Retrieved January 17, 2008.
  43. ^ Mangels, Reed. "Vitamin B12 in the Vegan Diet". Vegetarian Resource Group. Retrieved January 17, 2008.
  44. ^ "Don't Vegetarians Have Trouble Getting Enough Vitamin B12?". Physicians Committee for Responsible Medicine. Retrieved January 17, 2008.
  45. ^ "Anemia, Megaloblastic". NORD (National Organization for Rare Disorders). Retrieved 2021-05-09.
  46. ^ C., Robert; Brown, David (2003-03-01). "Vitamin B12 Deficiency". American Family Physician. 67 (5): 979–986. PMID 12643357.
  47. ^ "Individual Cases of B12 Deficiency in Vegans". VeganHealth.org. Retrieved 2021-11-30.
  48. ^ "B12 Deficiency Cases in Vegan Infants and Toddlers". VeganHealth.org. Retrieved 2021-11-30.
  49. ^ Krajčovičová-Kudláčková, M.; Blažíček, P.; Kopčová, J.; Béderová, A.; Babinská, K. (2000). "Homocysteine Levels in Vegetarians versus Omnivores". Annals of Nutrition and Metabolism. 44 (3): 135–8. doi:10.1159/000012827. PMID 11053901. S2CID 25418416.
  50. ^ "What Every Vegan Should Know About Vitamin B12". Retrieved 2015-08-05.
  51. ^ "Vitamin B12: Fact Sheet for Consumers" National Institutes of Health Office of Dietary Supplements (retrieved Dec 9, 2016)
  52. ^ "Scientific Opinion on Dietary Reference Values for cobalamin (vitamin B12)" European Food Safety Authority Panel on Dietetic Products, Nutrition and Allergies. EFSA Journal 2015;13(7):4150 [64 pp.].
  53. ^ "Don't Vegetarians Have Trouble Getting Enough Vitamin B12?" Physicians Committee for Responsible Medicine (retrieved Dec 9, 2016)
  54. ^ Watanabe, Fumio; Yabuta, Yukinori; Bito, Tomohiro; Teng, Fei (5 May 2014). "Vitamin B12-Containing Plant Food Sources for Vegetarians". Nutrients. 6 (5): 1861–1873. doi:10.3390/nu6051861. PMC 4042564. PMID 24803097.
    Watanabe, Fumio; Yabuta, Yukinori; Tanioka, Yuri; Bito, Tomohiro (2 July 2013). "Biologically Active Vitamin B12 Compounds in Foods for Preventing Deficiency among Vegetarians and Elderly Subjects". Journal of Agricultural and Food Chemistry. 61 (28): 6769–6775. doi:10.1021/jf401545z. PMID 23782218.
    Croft, Martin T.; Lawrence, Andrew D.; Raux-Deery, Evelyne; Warren, Martin J.; Smith, Alison G. (November 2005). "Algae acquire vitamin B12 through a symbiotic relationship with bacteria". Nature. 438 (7064): 90–93. Bibcode:2005Natur.438...90C. doi:10.1038/nature04056. PMID 16267554. S2CID 4328049.
  55. ^ Mangels, Messina and Messina 2011, 190, 297; Debra Wasserman, Reed Mangels, Simply Vegan, The Vegetarian Resource Group, 2006, 171; Mangels 2006.
  56. ^ Melina, Vesanto; Craig, Winston; Levin, Susan (December 2016). "Position of the Academy of Nutrition and Dietetics: Vegetarian Diets". Journal of the Academy of Nutrition and Dietetics. 116 (12): 1970–1980. doi:10.1016/j.jand.2016.09.025. PMID 27886704.
  57. ^ Fang H, Kang J, Zhang D (2017). "Microbial production of vitamin B12: a review and future perspectives". Microb Cell Fact (Review). 16 (1): 15. doi:10.1186/s12934-017-0631-y. PMC 5282855. PMID 28137297.
  58. ^ Riaz, Muhammad; Iqbal, Fouzia; Akram, Muhammad (2007). "Microbial production of vitamin B12 by methanol utilizing strain of Pseudomonas specie". Pakistan Journal of Biochemistry & Molecular Biology. 1. 40: 5–10. Archived from the original on 25 April 2012. Retrieved 15 December 2017.
  59. ^ a b Lusas, Edmund W. (2007). "Animal and Vegetable Fats, Oils, and Waxes". Kent and Riegel's Handbook of Industrial Chemistry and Biotechnology. pp. 1549–1656. doi:10.1007/978-0-387-27843-8_34. ISBN 978-0-387-27842-1.
  60. ^ Xia, Wei; Chen, Wei; Peng, Wei-fu; Li, Kun-tai (June 2015). "Industrial vitamin B12 production by Pseudomonas denitrificans using maltose syrup and corn steep liquor as the cost-effective fermentation substrates". Bioprocess and Biosystems Engineering. 38 (6): 1065–1073. doi:10.1007/s00449-014-1348-5. PMID 25561346. S2CID 42246117.
  61. ^ Reed Mangels, Virginia Messina, and Mark Messina, "Vitamin B12 (Cobalamin)", The Dietitian's Guide to Vegetarian Diets, Jones & Bartlett Learning, 2011, 181–192.
  62. ^ "Thyroid Hormone Toxicity: Background, Pathophysiology, Epidemiology". 2021-04-29. Cite journal requires |journal= (help)
  63. ^ Appleby, Paul N; Thorogood, Margaret; Mann, Jim I; Key, Timothy JA (1 September 1999). "The Oxford Vegetarian Study: an overview". The American Journal of Clinical Nutrition. 70 (3): 525s–531s. doi:10.1093/ajcn/70.3.525s. PMID 10479226.
  64. ^ "Iodine", Office of Dietary Supplements, National Institutes of Health. The RDA is 110 mcg (0–six months), 130 mcg (7–12 months), 90 mcg (1–8 years), 120 mcg (9–13 years), 150 mcg (14+). The RDA for pregnancy and lactation is 220 and 290 mcg respectively.
  65. ^ Remer, Thomas; Neubert, Annette; Manz, Friedrich (1999). "Increased risk of iodine deficiency with vegetarian nutrition". British Journal of Nutrition. 81 (1): 45–9. doi:10.1017/s0007114599000136. PMID 10341675.
  66. ^ "Veganism: Vitamin B12 is well supplemented, iodine is a matter of concern - BfR". www.bfr.bund.de. Retrieved 2021-11-30.
  67. ^ Mangels, Messina and Messina 2011, 71; for their chapter on protein, 65–79.
  68. ^ Mangels, Messina and Messina 2011, 72, 78.
  69. ^ Mangels, Messina and Messina 2011, 75ff.
  70. ^ Mangels, Messina and Messina 2011, 77.
  71. ^ "Office of Dietary Supplements - Omega-3 Fatty Acids".
  72. ^ Gerster, H. (1998). "Can adults adequately convert alpha-linolenic acid (18:3n-3) to eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3)?". International Journal for Vitamin and Nutrition Research. Internationale Zeitschrift Fur Vitamin- und Ernahrungsforschung. Journal International de Vitaminologie et de Nutrition. 68 (3): 159–173. PMID 9637947.
  73. ^ "How to Optimize Your Omega-6 to Omega-3 Ratio". 11 June 2018.
  74. ^ Sanders, Thomas A.B. (2009). "DHA status of vegetarians". Prostaglandins, Leukotrienes and Essential Fatty Acids. 81 (2–3): 137–41. doi:10.1016/j.plefa.2009.05.013. PMID 19500961.
  75. ^ Bouchez, Colette. "Good Fat, Bad Fat: The Facts About Omega-3". WebMD.
  76. ^ Craig, Winston J (2009-03-11). "Health effects of vegan diets". The American Journal of Clinical Nutrition. 89 (5): 1627S–1633S. doi:10.3945/ajcn.2009.26736N. ISSN 0002-9165. PMID 19279075.
  77. ^ Ho-Pham, L. T; Nguyen, N. D; Nguyen, T. V (2009). "Effect of vegetarian diets on bone mineral density: A Bayesian meta-analysis". American Journal of Clinical Nutrition. 90 (4): 943–50. doi:10.3945/ajcn.2009.27521. PMID 19571226.
  78. ^ Brody, Jane E. (May 8, 1990). "Huge Study Of Diet Indicts Fat And Meat". The New York Times.
  79. ^ Junshi, Chen; Campbell, T. Colin; Li; et al., eds. (1990). Diet, lifestyle, and mortality in China: a study of the characteristics of 65 Chinese counties. Oxford University Press. ISBN 978-0-19-261843-6.[page needed]
  80. ^ Byers, Tim (1992-05-15). "Book Reviews: Diet, lifestyle, and mortality in China: a study of the characteristics of 65 Chinese counties". American Journal of Epidemiology. 135 (10): 1180–1. doi:10.1093/oxfordjournals.aje.a116219.
  81. ^ Tai, Vicky; Leung, William; Grey, Andrew; Reid, Ian R.; Bolland, Mark J. (2015-09-29). "Calcium intake and bone mineral density: systematic review and meta-analysis". BMJ. 351: h4183. doi:10.1136/bmj.h4183. ISSN 1756-1833. PMC 4784773. PMID 26420598.
  82. ^ "Calcium Supplements: Should You Take Them?". www.hopkinsmedicine.org. Retrieved 16 October 2020.
  83. ^ "21 Vegetarian Foods That Are Loaded with Iron". 4 May 2017.
  84. ^ "Iron deficiency—adults". High-risk groups such as vegetarians, adolescent girls and women athletes need to eat iron-rich foods each day (combined with foods that are high in vitamin C). ... Vegetarians who exclude all animal products from their diet may need almost twice as much dietary iron each day as non-vegetarians. Sources include dark green leafy vegetables—such as spinach—and raisins, nuts, seeds, beans, peas, and iron-fortified cereals, breads and pastas
  85. ^ Larsson, CL; Johansson, GK (2002). "Dietary intake and nutritional status of young vegans and omnivores in Sweden". The American Journal of Clinical Nutrition. 76 (1): 100–6. doi:10.1093/ajcn/76.1.100. PMID 12081822.
  86. ^ Messina, MJ; Messina, VL (1996). The Dietitian's Guide to Vegetarian Diets: Issues and Applications. Gaithersburg, MD: Aspen Publishers.[page needed]
  87. ^ Craig, WJ (1994). "Iron status of vegetarians". The American Journal of Clinical Nutrition. 59 (5 Suppl): 1233S–1237S. doi:10.1093/ajcn/59.5.1233S. PMID 8172127.
  88. ^ Ball, MJ; Bartlett, MA (1999). "Dietary intake and iron status of Australian vegetarian women". The American Journal of Clinical Nutrition. 70 (3): 353–8. doi:10.1093/ajcn/70.3.353. PMID 10479197.
  89. ^ Hallberg, L; Brune, M; Rossander, L (1989). "The role of vitamin C in iron absorption". International Journal for Vitamin and Nutrition Research. Supplement. 30: 103–8. PMID 2507689. The key role of ascorbic acid for the absorption of dietary nonheme iron is generally accepted. The reasons for its action are twofold: (1) the prevention of the formation of insoluble and unabsorbable iron compounds and (2) the reduction of ferric to ferrous iron, which seems to be a requirement for the uptake of iron into the mucosal cells.
  90. ^ Lönnerdal, B (October 2010). "Calcium and iron absorption--mechanisms and public health relevance". Int J Vitam Nutr Res. 90 (4–5): 293–9. doi:10.1024/0300-9831/a000036. PMID 21462112.
  91. ^ Mangels, Messina and Messina 2011, 138ff, 143–144. For a detailed discussion, "Iron", Food and Nutrition Board, Institute of Medicine, National Academy Press, 2001, 290–393.
  92. ^ Mangels, Messina and Messina 2011, 146].
  93. ^ Mangels, Messina and Messina 2011, 143.
  94. ^ Davida Gypsy Breier, Reed Mangels, Vegan & Vegetarian FAQ, The Vegetarian Resource Group, 2001, 27.
  95. ^ a b Mangels, Messina and Messina 2011, 142; Reed Mangels, "Iron in the Vegan Diet", The Vegetarian Resources Group.
  96. ^ Sanders Tom A (1999). "The nutritional adequacy of plant-based diets". The Proceedings of the Nutrition Society. 58 (2): 265–9. doi:10.1017/S0029665199000361. PMID 10466165.
  97. ^ Haytowitz DB (2009). "Vitamin D in mushrooms" (PDF). Nutrient Data Laboratory, US Department of Agriculture. Retrieved 16 April 2018.
  98. ^ Keegan RJ, Lu Z, Bogusz JM, Williams JE, Holick MF (January 2013). "Photobiology of vitamin D in mushrooms and its bioavailability in humans". Dermato-Endocrinology. 5 (1): 165–76. doi:10.4161/derm.23321. PMC 3897585. PMID 24494050.
  99. ^ Wang, Ting; Bengtsson, Göran; Kärnefelt, Ingvar; Björn, Lars Olof (September 2001). "Provitamins and vitamins D2 and D3 in Cladina spp. over a latitudinal gradient: possible correlation with UV levels". Journal of Photochemistry and Photobiology B: Biology. 62 (1–2): 118–122. doi:10.1016/s1011-1344(01)00160-9. PMID 11693362.
  100. ^ Watson, Elaine (13 March 2012). "Veggie vitamin D3 maker explores novel production process to secure future supplies". NutraIngredients-USA. William Reed Business Media. Archived from the original on 22 March 2018. Retrieved 22 March 2018.
  101. ^ Mangels, Messina and Messina 2011, 209.
  102. ^ Ross et al. (Institute of Medicine) 2011, 75.
  103. ^ Björn, LO; Wang, T (2000). "Vitamin D in an ecological context". International Journal of Circumpolar Health. 59 (1): 26–32. ISSN 1239-9736. PMID 10850004.
  104. ^ Jäpelt, Rie B.; Jakobsen, Jette (2013). "Vitamin D in plants: a review of occurrence, analysis, and biosynthesis". Frontiers in Plant Science. 4: 136. doi:10.3389/fpls.2013.00136. ISSN 1664-462X. PMC 3651966. PMID 23717318.
  105. ^ Adi Menayang (29 April 2019). "AIDP: "There is a significant market potential for vegan D3"". NutraIngredients-USA, William Reed, Inc. Retrieved 10 August 2019.
  106. ^ "Why is everyone talking about choline and vegans? The truth behind the headlines". Vegan Food and Living. Retrieved 2021-05-09.
  107. ^ a b "Clearing Up Choline Confusion". Physicians Committee for Responsible Medicine. Retrieved 2021-05-09.
  108. ^ "Vegan and plant diets 'rob brain of crucial nutrient'". Sky News. Retrieved 2021-05-09.
  109. ^ Frost, Rosie (2019-08-30). "Could a plant-based diet be making you dumb?". euronews. Retrieved 2022-01-13.
  110. ^ Higdon, Jane (Nov 2003). "Choline". Linus Pauling Institute at Oregon State University. Retrieved 3 March 2014.
  111. ^ Nutrient Reference Values for Australia and New Zealand, 17 March 2014, Although choline is essential, there appear to have been no reports of deficiency in the general population. Deficiencies have been seen in experimental situations and also in total parenteral nutrition (Buchman et al. 1992, 1993, 1995, Chalwa et al. 1989, Shapira et al. 1986, Sheard et al. 1986).
  112. ^ "Choline". Office of Dietary Supplements, US National Institutes of Health. 26 September 2018. Retrieved 26 January 2019.