What Causes Iron Deficiency Anemia?

What Causes Iron Deficiency Anemia?

The World Health Organization (WHO) published data of over 12 years of research showing that approximately half of the 1.62 billion cases of anemia worldwide are due to iron deficiency [1] .  Anemia is a condition where the body lacks the nutrients to produce the appropriate amount of red blood cells. Iron is a major component of red blood cells. Iron deficiency anemia is common in the United States, especially among young children, women of reproductive age, and pregnant women. Because iron deficiency is associated with poor diet, malabsorptive disorders, and blood loss, people with iron deficiency usually have other nutrient deficiencies. 

Iron depletion and deficiency progresses through several stages [2]:

  1. Mild deficiency or storage iron depletion: Serum ferritin concentrations and levels of iron in bone marrow decrease.
  2. Marginal deficiency, mild functional deficiency, or iron-deficient erythropoiesis (erythrocyte production): Iron stores are depleted, iron supply to erythropoietic cells and transferrin saturation decline, but hemoglobin levels are usually within the normal range.
  3. IDA: Iron stores are exhausted; hematocrit and levels of hemoglobin decline; and the resulting microcytic, hypochromic anemia is characterized by small red blood cells with low hemoglobin concentrations.

Many women try to supplement their diet with lean red meat, dark leafy greens, nuts, seeds, and shellfish; however, many women remain severely deficient in this important supplement and Iron deficiency anemia remains a major reason for doctor visits in the United States [3]. Without enough iron, your body cannot produce enough of a substance in red blood cells (anemia) that enables them to carry oxygen (hemoglobin). As a result, iron deficiency anemia may leave you tired, weak, with cardiac risks and short of breath.


Iron Deficiency Anemia Symptoms


Symptoms of iron deficiency anemia include but are not limited to the following [4]:

  • Extreme fatigue
  • Weakness
  • Pale skin
  • Chest pain, fast heartbeat, or shortness of breath
  • Headache, dizziness, or lightheadedness
  • Cold hands and feet
  • Inflammation or soreness of your tongue
  • Brittle nails
  • Unusual cravings for non-nutritive substances, such as ice, dirt, or starch
  • Poor appetite, especially in infants and children with iron deficiency anemia


Who is at Risk for Iron Deficiency Anemia?


  1. Infants and young children

Infants—especially those born preterm or with low birthweight or whose mothers have iron deficiency—are at risk of iron deficiency because of their high iron requirements due to their rapid growth [5]. Full-term infants usually have sufficient iron stores and need little if any iron from external sources until they are 4 to 6 months old [6]. However, full-term infants have a risk of becoming iron deficient at 6 to 9 months unless they obtain adequate amounts of solid foods that are rich in bioavailable iron or iron-fortified formula.

  1. Women with heavy menstrual bleeding

Women of reproductive age who have heavy bleeding during menstruation, are at increased risk of iron deficiency. Women with heavy periods can lose significantly more iron per menstrual cycle on average than women with normal menstrual bleeding [7]. Limited evidence suggests that heavy menstruation may be responsible for about 33% to 41% of cases of iron deficiency anemia among women of reproductive age [7].

  1. People with cancer

Up to 60% of patients with colon cancer have iron deficiency at diagnosis, probably due to chronic blood loss [8]. The prevalence of iron deficiency in patients with other types of cancer ranges from 29% to 46%. There are many causes that lead to iron deficiency in cancer patients that are beyond the scope of this discussion but regardless the cause the requirement of iron does not change in these patients.

  1. People who have gastrointestinal disorders or have had gastrointestinal surgery

People with certain gastrointestinal disorders (such as celiac disease, ulcerative colitis, and Crohn’s disease) or who have undergone certain gastrointestinal surgical have an increased risk of iron deficiency because their disorder or surgery most likely will requires dietary restrictions or iron malabsorption [9,10]. The combination of low iron intake and poor iron absorption can lead to a reduced production of red blood cells and iron deficiency anemia.


How to take iron supplements for best absorption?


Once you have been diagnosed with low iron levels and the need for more iron in your diet then you must understand how our body absorbs iron best. Oral iron supplements are notorious for causing nausea, vomiting and constipation. Iron supplements come in a variety of the forms but regardless of iron being in the form of pills, gummies, tablets, or drinks they all cause the following symptoms when swallowed:

  • Constipation
  • Nausea
  • Vomiting
  • Possible staining of your teeth
  • Abdominal pain and cramping


How much iron supplement should you take?

Standard iron supplements contain 65 mg of elemental iron in a 325mg total tablet, that includes salts, additives, preservatives, coloring, coatings, etc. Iron supplement studies have shown overall poor absorption for all swallowed iron supplements from liquid to gummies to swallowed pills. Multiple daily dosing has become the standard of the industry to improve overall absorption which may possibly even worsen the absorption issue.

Also, with multiple dosing comes the worsening problem of side effects such as nausea and constipation that can lead to cessation of the supplement and worsening of the disease such as anemia. In a recent study in New England Journal of Medicine, study participants were given standard swallowed high dose iron tablets two to three times a day, but the results of their blood studies showed only absorptions of 22.6 to 23.6mg per day compared to the approximately 1000mg of total tablets that were being swallowed. 


The medical community still believes that intravenous iron is still a superior alternative due to less side effects and improved absorption. However, due to insurance push back doctors no longer can order such therapies with ease even in cancer patients. The unfortunate reality is that due to increasing cost of medicine the cost of intravenous Iron supplementation even in the most appropriate patients has become prohibitive.

The medical community believes that under the tongue absorption is possibly a more efficient method of absorption allowing similar if not better absorption than the current practice of multiple daily dosing of oral iron supplements. Future medical trials and studies comparing iron supplementation under the tongue vs. oral swallowed iron supplements and possibly even intravenous iron therapy should shed some light on the advantages of under the tongue absorption. The cost effectiveness of under the tongue iron supplements should be a new alternative for many needy patients that are unable to get appropriate therapies due to financial constraints.


This information is only for educational purposes and is not medical advice or intended as a recommendation of any specific products. Consult your health care provider for more information. These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.



  1. World Health Organization. Worldwide Prevalence of Anemia 1993–2005: WHO Global Database on Anemia. World Health Organization, 2008.
  2. World Health Organization. Report: Priorities in the Assessment of Vitamin A and Iron Status in Populations, Panama City, Panama, 15-17 September 2010. Geneva; 2012
  3. National Ambulatory Medical Care Survey: 2016 National Summary Tables; 2016, 1-43.
  4. “10 Signs and Symptoms of Iron Deficiency.” Healthlinehttps://www.healthline.com/nutrition/iron-deficiency-signs-symptoms.
  5. Domellöf M. Iron requirements in infancy. Ann Nutr Metab 2011;59:59-63. [PubMed abstract]
  6. Aggett PJ. Iron. In: Erdman JW, Macdonald IA, Zeisel SH, eds. Present Knowledge in Nutrition. 10th ed. Washington, DC: Wiley-Blackwell; 2012:506-20.
  7. Napolitano M, Dolce A, Celenza G, Grandone E, Perilli MG, Siragusa S, et al. Iron-dependent erythropoiesis in women with excessive menstrual blood losses and women with normal menses. Ann Hematol 2014;93:557-63. [PubMed abstract]
  8. Aapro M, Osterborg A, Gascon P, Ludwig H, Beguin Y. Prevalence and management of cancer-related anaemia, iron deficiency and the specific role of i.v. iron. Ann Oncol 2012;23:1954-62. [PubMed abstract]
  9. Bayraktar UD, Bayraktar S. Treatment of iron deficiency anemia associated with gastrointestinal tract diseases. World J Gastroenterol 2010;16:2720-5. [PubMed abstract]
  10. Gasche C, Berstad A, Befrits R, Beglinger C, Dignass A, Erichsen K, et al. Guidelines on the diagnosis and management of iron deficiency and anemia in inflammatory bowel diseases. Inflamm Bowel Dis 2007;13:1545-53. [PubMed abstract]
  11. Green, David. “Iron Dosing for Optimal Absorption.” NEJM Journal watch, 30 OCT 2015, https://www.jwatch.org/na39463/2015/10/30/iron-dosing-optimal-absorption.




Your Cart

Your shopping cart is empty.

$ 0.00 USD
Frunutta Dissolvable Vitamins