Iron (from baker’s yeast)

Iron. The human body uses iron (a mineral) to make a protein (hemoglobin) in red blood cells to carry oxygen throughout the body so that cells may produce energy 1, 2, 3.  There are two forms of dietary iron: heme and nonheme. Sources of heme iron include meat, fish and poultry. Sources of non-heme iron include plant and iron-fortified foods; beans, lentils, flours, cereals and grains 1, 2, 3. The iron requirement of the individuals determines the proportion of dietary iron absorbed 1.  Heme iron is more easily absorbed (has more bioavailability) than non-heme iron 1, 2, 3.  The absorption of non-heme iron is strongly influenced by its interaction with other meal components in the lumen of the upper small intestine and by its solubility, where as heme iron is always well absorbed and influenced only slightly by other dietary factors 1.

The risk of adverse effects from food sources of iron is low. The U.S. Food and Drug Administration (FDA) has established a Reference Daily Intake (RDI) of 18 mg iron for adults and children 4 or more years of age as per 21CFR101.9, ( 4.  RDIs are a set of dietary references for essential vitamins and minerals that are considered amounts sufficient to meet the daily requirements of healthy individuals. RDIs serve as the basis for calculating the percent daily value (%DV) amounts found on dietary supplement and food labels 4. Information is available on  Recommended Dietary Allowances (RDAs) by age and gender for the amount of iron that is recommended for daily intake  1, 2, 3.

Baker’s yeast (also called Brewer’s yeast) is used as a dietary source of B-complex vitamins, selinum, chromium and protein 5. Brewer’s yeast, as a group of specific strains of Saccharomyces cerevisiae yeast, is used as an ingredient in some nutritional and dietary supplements as well as for brewing ales 5, 6, 7.  Brewing beer dates back to 8,000 years ago.  In 1883, E. C. Hansen (Carlsberg Brewery) established the use of brewer’s yeast and other specific yeast strains as starter cultures in brewing 5. According to Science Direct, Baker’s yeast, a biotype of S. cerevisiae, is able to metabolize sugars both through producing the end products of carbon dioxide and water (meaning aerobically, with oxygen), and by producing carbon dioxide and ethanol (meaning anaerobically, without oxygen) 8.

Generally, yeast is a term generally applied to a unicellar fungus; however, baker’s yeast or brewer’s yeast is used as an energy booster, immune enhancer, protein supplement or other use toward a product 9.

This ingredient can be found in the following products in United States:


  1. Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, D.C.: National Academy Press, 2002. Accessed from ISBN: 978-0-309-07290-8
  2. National Institutes of Health (NIH). Office of Dietary Supplements (ODS). U. S. Dept. of Health & Human Services. Fact Sheet for Health Professionals. Iron. Updated 9/20/2018. Accessed 10/12/18. Accessed from
  3. Kohn J. Iron. Academy of Nutrition and Dietetics. Published 12/14/2017. Retrieved on 10/12/2018. Accessed from
  4. Food and Drug Administration (FDA). Code of Federal Regulations (CFR). Title 21. CFR21. Part 101.9 Nutrition labeling of food. 8 (B)(iv). Last updated 9/4/2018. Accessed on 10/12/2018. Accessed from
  5. Brewer’s Yeast. Health professional monograph.Product ID 715. Natural Medicines database. Last updated 8/9/2018. Accessed on 10/12/2018. Retrieved from,-herbs-supplements/professional.aspx?productid=715
  6. Jensen DP, Smith DL. Fever of unknown origin secondary to brewer’s yeast ingestion. Arch Intern Med 1976;136(3):332-333. PMID: 769716
  7. Ferreira IMPLVO, Pinho O, Vieira E, Tavarela JG. Brewer's Saccharomyces yeast biomass: characteristics and potential applications. Trends Food Sci Technol. 2010;21(2):77-84. Accessed from
  8. Deak T, in Enclopedia of Food Sciences and Nutrition 2003 (2nd Ed) as found on Science Direct. Saccharomyces cerevisiae. . Accessed 10/12/2018. Accessed from
  9. Moyad MA. Brewer’s/baker’s yeast (Saccharomyces cerevisiae) and preventive medicine: Part II. [Abstract]. Urol Nurse 2008; 28(1): 73-5.PMID: 18335702. Accessed from