As we gradually make our way out of the dark and dreary winter months, many of us may feel exhausted and drained by the daily rise and grind of work. Summer is just around the corner, but perhaps you haven’t felt that pep in your step, even as the days get longer. Maybe you’ve even noticed that you lack the energy for workouts that used to leave you feeling energized.
While you might be writing these feelings off as burnout or the winter blues, these nonspecific symptoms could be a sign of low iron. Iron is essential for the production of hemoglobin, the component of our blood that carries oxygen from our lungs to our cells. If iron stores are low, the body may not be receiving optimal oxygenation, leaving you feeling fatigued, cold, or dizzy and lightheaded.
How Do I Know if I Have Low Iron?
While the best way to determine if you have low iron is through a blood test, certain factors can predispose you to having low iron, including:
- Having a period – especially if your menstrual flow is quite heavy
- Being pregnant or breastfeeding
- Having gastrointestinal diseases such as celiac disease, inflammatory bowel disease, or ulcerative colitis
- Consuming a vegetarian or vegan diet
Predisposing factors in combination with the following symptoms can suggest low iron, indicating the need for a confirmatory blood test:
- Unexplained fatigue or lack of energy
- Feeling weak
- Rapid heartbeat
- Pounding or “whooshing” in the ears
- Cravings for ice
- Dizziness or lightheadedness
- Brittle nails or hair loss
While you may be able to screen for iron deficiency anemia with predisposing factors and signs and symptoms, laboratory tests are crucial to determine the severity of your iron deficiency, as well as the treatment. The following laboratory results can be indicative of iron deficiency anemia:
- Low hemoglobin and hematocrit
- Low mean cellular volume (MCV)
- Low ferritin
- Low serum iron (FE)
- High transferrin or total iron binding capacity (TIBC)
- Low iron saturation
Finally, your provider may choose to run other tests to rule out any red flag conditions that can present with similar symptoms. These may include testing for blood in the stool, looking for gastrointestinal tract abnormalities, testing the urine for blood, or investigating the cause of heavy menstrual bleeding.
What Causes Low Iron?
Our body’s iron levels primarily depend on two key factors: our iron input– made up of diet and absorption– and our iron output which occurs through blood loss.
Iron Input
Without supplementation, our diet is the only way to acquire iron. Foods rich in iron include red meat, liver, poultry, fish and shellfish, beans, leafy greens, and fortified products like pasta, grains, rice, and cereal. However, all iron-rich foods are not created equally, as heme iron found in animal products is more easily absorbed than non-heme iron found in plant sources.
Furthermore, certain foods can actually interfere with iron absorption. One example of this is phytates or phytic acid, a compound found in plant-based foods like whole grains, nuts, soy, and legumes. Another example is calcium found in dairy products, and oxalates found in plant-based foods like spinach and tea. Just because these foods can interfere with iron absorption doesn’t mean that we should avoid them; rather, this information can help us understand how much iron we are really getting from our diet, and whether or not we need to supplement.
Iron Output
The main way in which we lose iron is through blood loss, which is why people who menstruate are often iron deficient. Certain conditions such as uterine fibroids or endometriosis can cause heavier periods, thus exacerbating iron output each month. Additionally, gastrointestinal bleeding via ulcers, hemorrhoids, or colon issues can cause low iron, highlighting the importance of proper investigation, especially when low iron is seen in someone who is not menstruating. While it is considered “normal” for people who menstruate to have lower iron stores, deficiencies should be corrected to ensure optimal health and performance.
Strategies for Increasing and Maintaining Iron Levels
Diet: Dietary changes are often the first and most sustainable step in supporting healthy iron levels. Iron rich foods come in two forms: heme iron found in animal products which are more easily absorbed, and non-heme iron found in plants and fortified foods which are less easily absorbed. Looking for foods that pack a punch when it comes to iron? Consider the following:
- Heme iron sources: clams, mussels, oysters, beef liver, chicken liver, sardines, and red meat like steak or lamb
- Non-heme iron sources: cooked lentils, spinach, chickpeas, tofu, quinoa, pumpkin seeds, blackstrap molasses, and iron-fortified cereals or bread.
Did you know that cooking with a cast iron pan can also increase your iron? While the research shows mixed results, most studies suggest a minor to moderate increase in iron as a result of cooking with cast iron cooking ware.
Iron supplementation: While dietary modifications are a great first step, some individuals (especially those eating plant-based diets or with heavy menstrual periods) may require supplementation. Talk to your healthcare provider to discuss what supplementation dose and form is best for you. Enhancing absorption:
- Pair iron with vitamin C: Whether using diet or supplementation, one strategy to enhance iron absorption included pairing iron with vitamin C-containing foods like citrus fruits, tomatoes, bell peppers or strawberries.
- Pair heme iron with non-heme iron: Research suggests that pairing non-heme iron with heme iron can enhance absorption. For example, eating a spinach salad with grilled chicken will increase the amount of iron absorbed from the spinach.
- Soak, sprout, or ferment legumes: As discussed earlier, some plant-based iron contains phytates which interfere with iron absorption. To solve this problem, consider soaking beans, lentils and grains before cooking to reduce phytate levels. Consuming sprouted seeds and legumes is another strategy to help break down phytates and boost nutrient availability. Additionally, fermented food slike tempeh can significantly lower phytate content.
- Supplement every other day: Research suggests that taking iron supplementation every other day as opposed to every day can increase absorption. This is due to the production of a hormone called hepcidin which temporarily blocks iron absorption after supplementation. By spacing doses every other day, hepcidin has time to decrease, allowing for better absorption of the next dose and potentially fewer side effects like constipation.
IV iron: If your iron is exceptionally low or you do not tolerate iron supplementation, your doctor might consider IV iron – something that we offer at Friday Health. Consider booking in with one of our naturopathic doctors to see if you qualify for IV iron.
Iron output strategies: While in general, strategies for individuals with low iron will focus on increasing iron input, if you experience heavy menstrual bleeding, certain hormonal birth control options like an intrauterine device (IUD) can lessen menstrual bleeding. Talk to your primary care provider or book in with one of our naturopathic doctors to discuss options for reducing heavy menstrual bleeding.
Disclaimer: The content provided on this blog is intended for informational purposes only and should not be construed as medical advice. While we strive to present accurate and up-to-date information, the field of naturopathic medicine is continually evolving, and individual health circumstances vary. Therefore, the information herein may not apply to your specific health situation.
Please be aware that engaging with this blog does not establish a doctor-patient relationship. For personalized medical advice, diagnoses, or treatment plans, we recommend scheduling a consultation with a qualified naturopathic physician or other licensed healthcare provider.
In the event of a medical emergency, contact emergency services immediately.
References
American Society of Hematology. (n.d.). Iron-deficiency anemia. American Society of Hematology. Retrieved April 5, 2025, from https://www.hematology.org/education/patients/anemia/iron-deficiency-anemia
Cleveland Clinic. (2023, March 15). 52 foods high in iron. Cleveland Clinic. Retrieved April 5, 2025, from https://health.clevelandclinic.org/how-to-add-more-iron-to-your-diet
National Heart, Lung, and Blood Institute. (n.d.). Iron-deficiency anemia. National Institutes of Health. Retrieved April 5, 2025, from https://www.nhlbi.nih.gov/health-topics/iron-deficiency-anemia
Sharma, S., Khandelwal, R., Yadav, K., Ramaswamy, G., & Vohra, K. (2021). Effect of cooking food in iron-containing cookware on increase in blood hemoglobin level and iron content of the food: A systematic review. Nepal Journal of Epidemiology, 11(2), 994–1005. https://doi.org/10.3126/nje.v11i2.36682