Iron and Ferritin – High and Low Levels Explained

  • June 17, 2019
Ferritin and Iron

Written by Lesley Herrmann, MSc. CNC

Feeling groggy lately? Or, is it taking weeks to overcome a cold? Maybe it’s time to check your iron levels.  Iron is an essential micronutrient required for energy production and immune function, so it’s important to check iron levels on a routine basis.

About 70 percent of the body’s iron is found in hemoglobin, a component of the red blood cell, and in myoglobin, found in muscle cells (including the heart). Both hemoglobin and myoglobin are important for transferring and storing oxygen. Another 25 percent of the body’s iron is bound to a protein called ferritin. Most of the ferritin in our bodies is found in liver cells (hepatocyes) and immune cells (reticuloendothelial cells), with a very small amount circulating in the blood (1). The remaining 5 percent makes up certain enzymes and is used in the synthesis of neurotransmitters and collagen (2).

Ferritin is the best indicator of the body’s iron reserves. The body will store ferritin until it is time to make more red blood cells. When the body signals the cells to release ferritin, it is picked up by a helper protein called transferritin, which transports ferritin to the location where new red blood cells are made (in the bone marrow).

Optimal levels for serum iron are 85-130 ng/mL. Optimal levels for ferritin are 40-90 ng/mL.

Iron and Ferritin Deficiency

A doctor will issue a ferritin test, in addition to total iron test, if they suspect a deficiency. Just looking at total iron doesn’t provide all the information; you also need to check the iron stores. A low ferritin reading is the earliest indication of iron deficient anemia. Signs of iron deficient anemia include:

  • fatigue
  • low energy
  • shortness of breath
  • pale skin
  • dizziness
  • cold hands and feet
  • chronic infection
  • heavy menstrual bleeding

This condition can result from excessive menstrual bleeding, pregnancy, nutritional deficiencies, hypochlorhidria, recurring infection, or internal bleeding from ulcers, hemorrhoids, or colon cancer.  Menstruating women, vegetarians and vegans, young children, and the elderly are more susceptible to iron deficiency. Additionally, breast feeding can increase the need for iron by 0.5 to 1 mg per day (2).

Elevated Iron and Ferritin

Elevated total iron and ferritin levels are also a concern, primarily because iron is an oxidizer. Oxidized iron can damage arteries and the heart while an increase in free radical production can increase the risk of cancer.  Some of the signs of iron toxicity include (3):

  • depression
  • fatigue
  • infertility
  • elevated blood sugar
  • irregular heart rhythm
  • diarrhea or constipation
  • nausea
  • vomiting
  • abdominal pain
  • green-gray skin tone
  • adrenal dysfunction

High iron levels can result from unnecessary supplementation or frequent cooking in iron cook-ware. Donating blood is a healthy and helpful way to reduce iron level for otherwise healthy individuals. Individuals with other health conditions may need to see a physician for therapeutic phlebotomy. Men and post menopausal woman are at higher risk for high iron levels.

According to functional medicine, you should not have a triple digit ferritin level, even though conventional ranges have upper limits of 300+ ng/mL) (4). Elevated ferritin may result from hemochromatosis, a genetic disorder that causes the body to store too much iron, a risk for organs. Another important marker in confirming this condition is transferrin saturation (levels >45%). Transferrin saturation can be determined by dividing serum iron by total iron binding capacity (serum iron/TIBC). High levels of ferritin have also been seen in individuals with obesity, daily alcohol consumption, and liver damage from any cause. (5)

Elevated serum ferritin is a well known indicator of acute or chronic inflammation. However, it is unclear whether serum ferritin results from or causes inflammation or whether it is involved in a particular inflammatory cycle. It does however represent a consequence of cellular damage and stress. (6)


Getting iron from the diet is the best way to add this micronutrient to the body. There are two primary sources of nutritional iron: heme-iron and non-heme iron. Heme iron is found in animal sources such as high quality organic red meat, eggs, lamb, salmon, clams, and chicken, with the highest sources coming from beef liver (organic, grass-fed is best). Plant sources of non-hemi iron is found in organic blackstrap molasses, wheat bran, pumpkin seeds, sunflower seeds, millet, and almonds, with the highest source coming from kelp. Ascorbic acid (vitamin C) and cysteine can help improve the absorption of iron. Eating organic red meat and other animal sources of heme-iron as part of a whole-food based meal is recommended for individuals with low iron and ferritin levels.

Iron absorption can be inhibited by phytic acid, a compound found in many foods fundamental to a vegetarian and vegan diet, including nuts, beans, lentils, wheat, rice, lentils, and tofu (7). Soaking these foods before eating them can reduce phytic acid levels and increase the iron that is available for assimilation. Iron absorption can also be inhibited by polyphenolic compounds (also found in plant foods), calcium, and insufficient hydrochloric acid in the stomach, which is essential for the digestion of protein, especially animal protein – the primary source of dietary iron. (8)

Adding a comprehensive iron test, including serum iron, serum ferritin, and total iron binding capacity, is a simple way to test your body’s overall iron balance. Testing these factors on a regular basis is recommended as part of a proactive health screening.  

To learn more about Lesley Herrmann please visit http://www.awakenedtaste.com/


  1. Nall, R. (2017). What is Ferritin. Available at https://www.healthline.com/health/ferritin#ferritin
  2. University of California San Francisco. Hemoglobin and Functions of Iron. Available at https://www.ucsfhealth.org/education/hemoglobin_and_functions_of_iron/
  3. Iron Disorders Institute. (2009). Iron Overload. Available at http://www.irondisorders.org/iron-overload
  4. Mercola, J. (2009). Little know secrets about optimal iron levels.  Available at https://articles.mercola.com/sites/articles/archive/2009/07/14/little-known-secrets-about-optimal-iron-levels.aspx
  5. Adams, P. (2008). Management of Elevated Serum Ferritin Levels.  Gastroenterology and Hepatology. May 2008; 4(5): 333-334. Available at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3093720/
  6. Kell, D.B and Pretorius E. (2014). Serum ferritin as an important inflammatory disease marker, as it is mainly a leakage product from damaged cells. Metallomics. April 2014.; 6(4(: 748-73. Available at https://www.ncbi.nlm.nih.gov/pubmed/24549403
  7. Arnarson, A. (2018). Phytic Acid 101: Everything You Need to Know. Available at https://www.healthline.com/nutrition/phytic-acid-101#section2
  8. Bland, J. et al. (2006). Clinical Nutrition: A Functional Approach Second Edition. Institute for Functional Medicine, pp 176-180.