Iron is an essential trace mineral required for haemoglobin synthesis — the protein in red blood cells that carries oxygen — and for myoglobin (oxygen storage in muscle), as well as dozens of enzymes involved in energy metabolism, DNA synthesis, and immune function. Iron deficiency is the most prevalent nutritional deficiency globally, affecting an estimated 2 billion people, and iron deficiency anaemia is the leading cause of anaemia worldwide.
Haem vs non-haem iron
Dietary iron exists in two forms. Haem iron is found in animal products — meat, poultry, and fish — where iron is bound within a porphyrin ring (as in haemoglobin and myoglobin). Haem iron is absorbed at roughly 15–35% efficiency and is not affected by most dietary enhancers or inhibitors. Non-haem iron is found in plant foods and is the form used in most iron supplements. It is absorbed at much lower efficiency (2–20%), and its absorption is significantly influenced by what else is consumed at the same time.
Ferrous vs ferric iron
Iron supplements come in two valence states: ferrous (Fe²⁺) and ferric (Fe³⁺). Ferrous iron is more readily absorbed, as the intestinal transporter (DMT-1) that moves iron across the gut wall specifically handles the ferrous form. Ferric iron must first be reduced to ferrous iron in the acidic environment of the stomach before it can be transported.
Common ferrous salts include ferrous sulfate (the most widely used pharmaceutical iron), ferrous gluconate, and ferrous fumarate. Ferric forms (such as ferric ammonium citrate) are generally less well absorbed but may cause fewer gastrointestinal side effects in some people.
Iron bisglycinate: the chelated advantage
Iron bisglycinate is iron chelated with two glycine molecules — a form that bypasses the normal ionic iron absorption pathway. Because it is absorbed as a chelate (rather than as free iron ions), it is less affected by inhibitors in food (such as phytates in whole grains and polyphenols in tea and coffee) and causes significantly less gastrointestinal irritation than ferrous sulfate. Studies comparing iron bisglycinate with ferrous sulfate have found comparable or superior increases in ferritin and haemoglobin with fewer side effects at equivalent doses.
What enhances and inhibits absorption
Vitamin C (ascorbic acid) is the most effective enhancer of non-haem iron absorption — consuming 50–100 mg of vitamin C with an iron supplement can roughly double absorption. Eating iron-rich foods or supplements with a meal containing tea, coffee, calcium-rich dairy, or phytate-containing grains significantly reduces absorption. For this reason, iron supplements are often recommended to be taken on an empty stomach or with a small amount of food to reduce nausea, alongside vitamin C.
Iron supplements in Lebanon
Supplements & More stocks iron supplements from US brands including chelated iron bisglycinate, available with cash on delivery across Lebanon.