Iron deficiency is a very common problem and can manifest itself with often nonspecific symptoms, such as chronic fatigue, difficulty concentrating, pallor, hair loss, or increased susceptibility to infections. Although often associated with a simple dietary deficit, iron deficiency is almost always the result of a combination of factors involving absorption, inflammation, and gastrointestinal function.
Iron is an essential micronutrient involved in numerous physiological processes, including oxygen transport, energy production, and supporting immune defenses. For this reason, even a mild deficiency can have a significant systemic impact.
The most common mechanisms underlying iron deficiency are:
- reduced dietary intake, common in vegetarian or vegan diets, or in monotonous diets, or in periods of increased need (such as during pregnancy);
- malabsorption due to gastrointestinal disorders such as hypochlorhydria (reduced gastric acidity), celiac disease, inflammatory bowel disease, intestinal dysbiosis;
- in conditions of chronic inflammation, where intestinal iron absorption and its mobilization from reserves are eliminated;
- in the presence of bleeding, typical in women with heavy menstruation, but also in those with problems with ulcers, gastrointestinal bleeding, prolonged use of painkiller/anti-inflammatory drugs.
From a nutritional point of view, there are two forms of iron, depending on their chemical structure: heme iron, present in animal foods such as red meat, poultry and fish, and non-heme iron, present in plant foods such as legumes, leafy vegetables, whole grains.
Heme iron is absorbed more (15–35%) than non-heme iron (2–20%), which is affected by many factors that reduce its absorption.
Then there are foods that promote or reduce iron absorption.
- Improving iron absorption is vitamin C, found in citrus fruits, kiwis, peppers, berries, etc. This vitamin is the most powerful promoter of non-heme iron absorption: it transforms ferric iron into ferrous iron, which is more easily absorbed. A simple squeeze of lemon on vegetables or legumes greatly increases the bioavailability of iron.
- Fermented foods such as yogurt, kefir, sauerkraut, kimchi, sourdough bread, and fermented vegetables: Fermentation reduces phytates (natural iron inhibitors) and improves gastric acidity.
- Foods rich in organic acids such as vinegar (e.g., apple cider vinegar), lemon, pickled vegetables, and marinated foods; acids help improve iron absorption.
- Herbs, spices, and digestive condiments such as ginger, turmeric, cumin, chili pepper, garlic, and onion, which support digestion and gastric function, indirectly promoting iron absorption.
- Foods rich in beta-carotene such as carrots, squash, sweet potatoes, apricots, spinach (cooked), a substance that, together with vitamin C, promotes the absorption of iron.
Preparation techniques can also promote the absorption of iron, especially non-heme iron (of plant origin), which is more difficult to absorb. First of all we have soaking the legumes, preferably with lemon or vinegar, for 8–12 hours to reduce phytates. Another strategy, an old traditional trick, is cooking in cast iron pots because when cooking acidic food (e.g. tomato sauce) small amounts of iron pass into the food. Light toasting of grains and seeds before cooking (e.g. spelt, barley, buckwheat, pumpkin or sunflower seeds) also inactivates some of the phytates. Acid marinade with lemon, vinegar, yogurt, citrus juice, reduces phytates and improves iron absorption. Another technique is germination, that is, sprouting legumes, seeds or cereals for 1–3 days. Thanks to this technique, phytates are further reduced, vitamins C and B are increased and the bioavailability of iron is improved. Finally, long cooking for legumes and cereals further reduces antinutrients and increases iron availability.
Foods that hinder iron absorption include: tea and coffee, cocoa, red wine, whole grains, high-calcium dairy products (because they compete when taken with iron sources), and eggs that have been cooked for too long.
It is important to understand that iron deficiency is not a simple low-iron problem, but a biological signal involving diet, absorption, inflammation, and metabolism. We need to understand the causes, preventing relapses and promoting more lasting restoration.
A proper diet, combined with the correction of gastrointestinal and inflammatory factors, is the basis for maintaining optimal iron levels.
(Article by Dr. Maddalena Della Bianca)
