Iron deficiency is the most common nutritional deficiency worldwide. Globally, 25-30% of the population is anemic. Half of this population has anemia caused by iron deficiency. According to estimates, about 40% of women have had iron deficiency anemia at some point in their lives.
Iron deficiency can cause a weakened immune system, fatigue, and anemia. Iron is an essential mineral for many bodily processes, such as the production of hemoglobin, the molecule that carries oxygen throughout the body. When iron levels are too low, the body can become hemoglobin deficient, leading to anemia.
When in deficit, the body gives clear signals, but these are often ignored or confused with simple “daily fatigue”, stress and or even
depression. This can cause symptoms such as fatigue, shortness of breath, and a weakened immune system, making it harder to fight off illness. Low iron levels can also affect cognitive development, as iron is necessary for the growth and maturation of neurons.
Fortunately, there are many different ways to correct an iron deficiency.
In the Integrative Functional Medicine and Naturopathy approach, understanding these signs is the first step to regaining vitality and preventing future complications.
How to recognize iron deficiency
- Persistent fatigue and lack of energy
- Paleness or drier skin than normal
- Hair loss or brittle nails
- Difficulties with concentration and memory
- Dizziness or feeling short of breath even with light exertion
- Cravings for unusual foods or substances
Anemia: When Iron Deficiency Becomes Clinical
Iron deficiency anemia is the most common form of anemia in the world.
It is characterized by a reduction in hemoglobin and healthy red blood cells, which are responsible for transporting oxygen.
It can result from iron-poor diets, significant menstrual leakage, gastrointestinal problems, or impaired absorption.
Functional approach to iron deficiency
In functional medicine, we don't just look to "correct" the deficiency, but to understand the causes: impaired intestinal absorption? Menstrual bleeding or hidden bleeding, celiac disease, autoimmune diseases? A diet with low iron bioavailability?
By identifying the root of the problem, it is possible to act in a personalized way, adjusting diet, supplementation and lifestyle.
Type of Iron: Differences Between Heme Iron vs. Non-Heme Iron
Heme iron is found in animal sources. Heme iron is easier for your body to absorb, making it a great way to increase your overall iron levels.
Sources of heme iron include (per 100g):
- Organ meats (liver, kidney, heart, etc.): 6.5-12.2 mg
- Seafood (oysters, clams, mussels, etc.): 2.6-14.0 mg
- Red meats (beef, pork, lamb, etc.): 1.5-5.5 mg
- Poultry (chicken, turkey, duck, etc.): 0.7-4.4 mg
- Eggs: 1.4 mg
- Fish (salmon, tuna, mackerel, etc.): 0.3-3.3 mg
Non-heme iron, on the other hand, is found in plant sources such as vegetables, nuts, seeds, dark leafy greens, and certain grains.
Sources of non-heme iron include (per 100g):
- Dried basil (90 mg) and dried nettle (4.4 mg)
- Legumes (beans, lentils, peas, etc.): 3.2-9.7 mg
- Tofu and tempeh: 2.7-5.6 mg
- Dark green leafy vegetables (spinach, cabbage, kale, etc.): 0.8–6.4 mg
- Nuts and seeds (pumpkin, squash, sesame, etc.): 2-6.3 mg
- Nuts (apricots, raisins, prunes, etc.): 1.5-5.2 mg
- Whole grains (oats, quinoa, brown rice, etc.): 1.3-3.4 mg
Nutritional factors that inhibit iron absorption:
- Phytates (phytic acid) present in various foods (abundant in legumes, whole grains, nuts and seeds)
- Phenolic compounds present in coffee, tea and herbal tea
- Soy protein (contains phytates)
- Calcium (inhibits the absorption of heme iron and non-heme iron)
Nutrients that can help the body absorb and use iron better and faster
- Vitamin C - has been shown to significantly improve iron absorption, and some experts suggest that taking it simultaneously with iron can increase absorption by up to three times.
- Copper - is another essential nutrient involved in the absorption and transport of iron in the body and is found in organ meats, seafood, nuts, and dark chocolate.
- Vitamin B12 - plays a vital role in iron absorption, helping to break down dietary proteins, supporting digestion and red blood cell formation. It also helps convert dietary iron into a usable form. Vitamin B12 is found naturally in animal products such as meat, poultry, eggs, and fish.
- Vitamin A - helps increase the production of a protein called transferrin, which binds to dietary iron and helps transport it to cells for absorption. Vitamin A also helps create an acidic environment for iron absorption. Vitamin A is found naturally in animal products such as liver and eggs.
- Selenium - Helps increase the activity of enzymes needed to convert iron from dietary sources into usable forms. Selenium is also essential for the healthy development of red blood cells, which help transport iron throughout the body. Selenium can be found naturally in certain foods, such as Brazil nuts, tuna, and brown rice.
- Zinc - helps the body convert dietary iron into a usable form. Zinc also helps regulate iron metabolism and is necessary for red blood cell production and healthy immune system function. Dietary sources of zinc include seafood, red meat, beans, nuts, whole grains, and dairy.
Iron absorption is less efficient if you are deficient in any of these nutrients, so make sure you get enough if you are trying to correct your iron deficiency.
Best practices to support iron levels
- Choose foods rich in heme iron (lean red meat and poultry) and non-heme iron (red beans, spinach, kale).
- Combine plant-based iron with vitamin C (e.g., beans + red pepper).
- Dried fruits, such as raisins, dried apricots, and prunes, daily
- Reduce your consumption of coffee, black tea and dairy products with main meals, as they hinder absorption.
- Ensure good intestinal health, as it is in the intestine that iron is absorbed.
- Perform regular tests and evaluate the following biomarkers: ferritin, transferrin, transferrin saturation, serum iron and hemoglobin.
- Respect rest cycles and restorative sleep, which are essential for cell regeneration.
When to consider supplementation
Iron supplementation is especially indicated in cases of:
- Anemia diagnosed
- Low ferritin
- Women of childbearing age with heavy periods
- Pregnant and lactating women
- People with inflammatory bowel disease or malabsorption
- Athletes with high physical demands
Modern supplements offer safer formulas, with better gastrointestinal tolerance, such as iron bisglycinate, and greater bioavailability. Some combinations include vitamin C, B12, or folic acid to optimize iron utilization.
Our recommended supplements for anemia:
For those who need extra support, we suggest high absorption and tolerance formulas:
QuattroFerrin 21 60cap - Biogena
Iron deficiency is more common than we think and can be the cause of that fatigue that never seems to go away.
With a functional approach, which includes conscious eating, good lifestyle practices and targeted supplementation, it is possible to regain energy, focus and vitality in a lasting way.
