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Difference between revisions of "Draft:Iron"

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(Summary)
(Dietary Guidelines)
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=== Dietary Guidelines ===
 
=== Dietary Guidelines ===
 
<-- summarize guidelines. should we supplement, if so when? are supplements dangerous?
 
<-- summarize guidelines. should we supplement, if so when? are supplements dangerous?
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* Due to the risks associated with excessive iron consumption (described above), studies suggest that only those who have been diagnosed with iron deficiency anemia should take supplements. One study found that oxidative stress even occurred in the bodies of women with anemia after they took iron supplements.<ref>Mani Tiwari, Amit Kumar, Abbas Ali Mahdi, Sudarshna Chandyan, Fatima Zahra, Madan Mohan Godbole, Shyam Pyari Jaiswar, Vinod Kumar Srivastava, and Mahendra Pal Singh Negi. “Oral Iron Supplementation Leads to Oxidative Imbalance in Anemic Women: A Prospective Study.” Clinical Nutrition 30, no. 2 (April 2011): 188–93. Accessed February 9, 2020. https://doi.org/10.1016/j.clnu.2010.08.001.</ref> As a result, nutrition expert Dr. Michael Greger recommends attempting to treat anemia with iron-rich plant foods before resorting to supplementation.<ref>Risk Associated with Iron Supplements | NutritionFacts.Org. Accessed February 9, 2020. https://nutritionfacts.org/video/risk-associated-with-iron-supplements/.</ref>
  
 
=== Sources of Iron ===
 
=== Sources of Iron ===

Revision as of 07:58, 9 February 2020

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<-- Note that we want only enough information to convincingly support the assertions made in the summary, and to counter inaccurate information. When making a point, it is important to find those sources that will result in the most convincing arguments, and to summarize findings in the most convincing manner, all without misrepresenting or exaggerating those sources. -->

<-- Good places to start research are in the "see also" section -->

<-- User Choline as a guide -->

Fact Sheet

Summary

Studies show that those who eat meatless diets are no more at risk of iron deficiency than meat-eaters,[1] and may even have higher iron levels.[2] Furthermore, heme iron (found only in animal products) has been linked to chronic diseases such as heart disease[3] and lung cancer.[4] In contrast, non-heme iron has not been linked to any diseases.

Context

  • Iron is an essential mineral used to transport oxygen through the body.[5]
  • Many people believe that red meat is the only good source of iron, despite the fact that there are several excellent plant-based sources.[5] Research has also suggested that non-heme iron (found in both plants and animal products) may be less well absorbed than heme iron (found only in animal products, mainly red meat).[6] This has led to claims that vegans are at risk of iron deficiency.

Evidence

<-- research and expert testimonials showing that plant-based diets are sufficient, and that heme-iron has risks, and addressing the increased risk of iron deficiency for vegans (is it true? It might be.) -->

  • Studies show that those who eat meatless diets are no more at risk of iron deficiency than meat-eaters,[1] and may even have higher iron levels.[2]
  • Research suggests that each milligram of heme iron consumed daily increases the risk of heart disease by 27 percent,[7] Type 2 diabetes by 16 percent,[8] and cancer by up to 12 percent.[9] Heme iron consumption has also been shown to increase stroke risk.[10]
  • The lower bioavailability of non-heme iron has long been considered a disadvantage. However, more recently it has been suggested that it may in fact be beneficial as it prevents too much iron from being absorbed. The body is able to regulate how much non-heme iron it absorbs from food, increasing or decreasing absorption as needed. Heme iron, on the other hand, passes straight into the bloodstream even if levels are already too high.[11][12] This iron overload contributes to the chronic diseases mentioned above, as iron is a pro-oxidant and can cause DNA damage and oxidative stress.[13][14]
  • Consuming vitamin C along with non-heme iron increases absorption of the iron.[15] Balanced plant-based diets are very high in vitamin C, which may explain why iron deficiency rates do not seem to be higher among those eating meatless diets.

Conflicting Claims

<-- major sources of conflicting claims and why they are false or dubious -->

Dietary Guidelines

<-- summarize guidelines. should we supplement, if so when? are supplements dangerous?

  • Due to the risks associated with excessive iron consumption (described above), studies suggest that only those who have been diagnosed with iron deficiency anemia should take supplements. One study found that oxidative stress even occurred in the bodies of women with anemia after they took iron supplements.[16] As a result, nutrition expert Dr. Michael Greger recommends attempting to treat anemia with iron-rich plant foods before resorting to supplementation.[17]

Sources of Iron

<-- foods, supplements -->

See Also

Plain Text

Footnotes

  1. 1.0 1.1 Saunders, Angela V., Winston J. Craig, Surinder K. Baines, and Jennifer S. Posen. “Iron and Vegetarian Diets.” The Medical Journal of Australia 199, no. S4 (19 2013): S11-16.
  2. 2.0 2.1 Farmer, Bonnie, Brian T. Larson, Victor L. Fulgoni, Alice J. Rainville, and George U. Liepa. “A Vegetarian Dietary Pattern as a Nutrient-Dense Approach to Weight Management: An Analysis of the National Health and Nutrition Examination Survey 1999-2004.” Journal of the American Dietetic Association 111, no. 6 (June 2011): 819–27. Accessed February 7, 2020. https://doi.org/10.1016/j.jada.2011.03.012.
  3. Hunnicutt, Jacob, Ka He, and Pengcheng Xun. “Dietary Iron Intake and Body Iron Stores Are Associated with Risk of Coronary Heart Disease in a Meta-Analysis of Prospective Cohort Studies.” The Journal of Nutrition 144, no. 3 (March 1, 2014): 359–66. Accessed February 7, 2020. https://doi.org/10.3945/jn.113.185124.
  4. Lam, Tram Kim, Melissa Rotunno, Brid M. Ryan, Angela C. Pesatori, Pier Alberto Bertazzi, Margaret Spitz, Neil E. Caporaso, and Maria Teresa Landi. “Heme-Related Gene Expression Signatures of Meat Intakes in Lung Cancer Tissues.” Molecular Carcinogenesis 53, no. 7 (July 2014): 548–56. Accessed February 7, 2020. https://doi.org/10.1002/mc.22006.
  5. 5.0 5.1 “Office of Dietary Supplements - Iron.” Accessed February 7, 2020. https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/.
  6. Hurrell, Richard, and Ines Egli. “Iron Bioavailability and Dietary Reference Values.” The American Journal of Clinical Nutrition 91, no. 5 (May 1, 2010): 1461S-1467S. https://doi.org/10.3945/ajcn.2010.28674F.
  7. Yang, Wei, Bin Li, Xiao Dong, Xiao-Qiang Zhang, Yuan Zeng, Jian-Liang Zhou, Yan-Hua Tang, and Jian-Jun Xu. “Is Heme Iron Intake Associated with Risk of Coronary Heart Disease? A Meta-Analysis of Prospective Studies.” European Journal of Nutrition 53, no. 2 (March 2014): 395–400. Accessed February 7, 2020. https://doi.org/10.1007/s00394-013-0535-5.
  8. Bao, Wei, Ying Rong, Shuang Rong, and Liegang Liu. “Dietary Iron Intake, Body Iron Stores, and the Risk of Type 2 Diabetes: A Systematic Review and Meta-Analysis.” BMC Medicine 10, no. 1 (December 2012): 119. Accessed February 7, 2020. https://doi.org/10.1186/1741-7015-10-119.
  9. Fonseca-Nunes, A., P. Jakszyn, and A. Agudo. “Iron and Cancer Risk--A Systematic Review and Meta-Analysis of the Epidemiological Evidence.” Cancer Epidemiology Biomarkers & Prevention 23, no. 1 (January 1, 2014): 12–31. Accessed February 7, 2020. https://doi.org/10.1158/1055-9965.EPI-13-0733.
  10. Kaluza, Joanna, Alicja Wolk, and Susanna C. Larsson. “Heme Iron Intake and Risk of Stroke: A Prospective Study of Men.” Stroke 44, no. 2 (February 2013): 334–39. Accessed February 7, 2020. https://doi.org/10.1161/STROKEAHA.112.679662.
  11. Sharp, Paul A. “Intestinal Iron Absorption: Regulation by Dietary & Systemic Factors.” International Journal for Vitamin and Nutrition Research 80, no. 45 (October 2010): 231–42. Accessed February 7, 2020. https://doi.org/10.1024/0300-9831/a000029.
  12. Geissler, Catherine, and Mamta Singh. “Iron, Meat and Health.” Nutrients 3, no. 3 (February 28, 2011): 283–316. Accessed February 7, 2020. https://doi.org/10.3390/nu3030283.
  13. “Prooxidant Iron and Copper, with Ferroxidase and Xanthine Oxidase Activities in Human Atherosclerotic Material.” FEBS Letters 368, no. 3 (July 24, 1995): 513–15. Accessed February 9, 2020. https://doi.org/10.1016/0014-5793(95)00726-P.
  14. Giulivi, Cecilia, and Enrique Cadenas. “The Reaction of Ascorbic Acid with Different Heme Iron Redox States of Myoglobin: Antioxidant and Prooxidant Aspects.” FEBS Letters 332, no. 3 (October 18, 1993): 287–90. Accessed February 9, 2020. https://doi.org/10.1016/0014-5793(93)80651-A.
  15. Hallberg, L., M. Brune, and L. Rossander. “The Role of Vitamin C in Iron Absorption.” International Journal for Vitamin and Nutrition Research. Supplement = Internationale Zeitschrift Fur Vitamin- Und Ernahrungsforschung. Supplement 30 (1989): 103–8.
  16. Mani Tiwari, Amit Kumar, Abbas Ali Mahdi, Sudarshna Chandyan, Fatima Zahra, Madan Mohan Godbole, Shyam Pyari Jaiswar, Vinod Kumar Srivastava, and Mahendra Pal Singh Negi. “Oral Iron Supplementation Leads to Oxidative Imbalance in Anemic Women: A Prospective Study.” Clinical Nutrition 30, no. 2 (April 2011): 188–93. Accessed February 9, 2020. https://doi.org/10.1016/j.clnu.2010.08.001.
  17. Risk Associated with Iron Supplements | NutritionFacts.Org. Accessed February 9, 2020. https://nutritionfacts.org/video/risk-associated-with-iron-supplements/.

Meta

This fact sheet was originally authored by ??? with contributions by Greg Fuller. The contents may have been edited since that time by others.