What are the symptoms of low iron?

Low iron is quite common, particularly among women of reproductive age and people who follow a low-iron diet. When iron levels decrease, it can result in iron deficiency anemia, which is characterized by fatigue, weakness, pale skin, and headaches (1).

Why is iron so important?
Iron is an essential mineral with numerous important functions in the body. It is a component of hemoglobin and myoglobin, two proteins that carry oxygen–hemoglobin in red blood cells and myoglobin in muscle cells. Iron is also important for physical growth, neurological development, cell functions, and the production of some hormones (2).

What are the signs of iron deficiency?
Usually, iron deficiency develops slowly as it may take a few months for the body’s iron stores to be depleted. Often mild iron deficiency doesn’t cause any symptoms, but if the iron levels continue to fall, other signs and symptoms can occur (3). These include:

  • Brittle nails
  • Pale skin
  • Tongue swelling or pain
  • Chest pain
  • Difficulty concentrating and dizziness
  • Fatigue and weakness
  • Headache
  • Irregular heartbeat
  • Shortness of breath
  • Pica (unusual craving for non-food items, e.g., ice, clay

Can iron deficiency cause further complications?
Yes, if severe iron deficiency is not treated, it can lead to serious complications, including:

  • Depression
  • Heart problems (e.g., arrhythmias, enlarged heart)
  • Increased susceptibility to infections
  • Development delays in children
  • Pregnancy complications (e.g., preterm delivery, low birth weight)

Who is most at risk of iron deficiency?
In developed countries, the populations most at risk for iron deficiency are:

  • Pregnant women: red blood cell production increases a lot during pregnancy, so lots more iron is required. Iron deficiency during pregnancy increases the risk of premature birth and low birth weight.
  • Infants and young children are growing so quickly so have high iron requirements. Infants that are born prematurely or with low birth weight or to iron-deficient mothers are the most at-risk.
  • Women with heavy menstrual bleeding lose more blood each month, and with that blood, they lost more iron.
  • Frequent blood donors due to the iron lost with each blood donation.
  • Cancer patients, particularly those with chronic blood loss (e.g., colon cancer)
  • People with gastrointestinal issues (e.g., celiac disease) or have had gastrointestinal surgery may have reduced absorption of iron from food, or have to follow dietary restrictions that affect iron absorption
  • People with heart failure, which may be caused by poor nutrition or absorption, or the use of oral anticoagulants may contribute to increased blood loss.
  • Vegetarians and vegans may be at increased risk, as they consume less heme iron, which is found in animal sources and is more easily absorbed than non-heme iron from plant sources.

How can I get my iron levels checked?
We offer several tests that can determine your iron status. All of these tests just require a simple finger prick blood sample for an accurate analysis.

  • The iron test measures the levels of iron circulating in the blood. In some instances, people with low iron levels may actually have normal iron levels circulating in the blood but still have low iron stores.
  • Ferritin is a protein that helps store iron. The ferritin test measures how much of the iron stores have been used. Low ferritin levels (below 10 mg/dL) are indicative of iron deficiency.
  • Transferrin is the main protein that binds and transports iron around the body. The transferrin test measures your levels of transferrin, while the transferrin saturation test calculates the percentage of transferrin that is bound to iron. Transferrin saturation levels below 20% indicate iron deficiency.

These tests are available as individual tests as well as a cost-saving combination test.

1. Iron-Deficiency Anemia. American Society of Hematology.
2. Iron, Fact Sheet for Health Professionals. NIH. Updated March 2021.
3. Iron-Deficiency Anemia. National Heart, Lung, and Blood Institute. NIH.