Dietary iron is found in heme (10%) and non-heme (ionic, 90%) forms and their absorption occurs in duodenum. Dietary non-heme iron primarily exists in an oxidized (Fe3+) form that is not bioavailable, and must first be reduced to the Fe2+ form by a ferrireductase enzyme, before it is transported across the intestinal epithelium by a transporter called divalent metal transporter 1 (DMT-1), which also transports other metal ions such as zinc, copper and cobalt (that is why those metals compete with iron for adsorption). Because the amount of DMT-1 is limited, the maximum daily adsorption of Iron is limited as well. There is a good reason why the body limits the adsorption of Iron. That is die to Iron’s capacity to regulate oxidative processes in the body. Too much or too little Iron can seriously jeopardize oxygen functions and body metabolism. Everyone is familiar with Iron’s the most important function: to transport oxygen in blood. There are also about 150000 different chemical processes based on the Iron-containing enzymes. Our muscular system, liver, thyroid gland wouldn’t perform their functions without Iron. Our wounds wouldn’t heal without Iron. Iron deficiency can seriously compromise cognitive functions, causing mental fatigue,
forgetfulness, difficulties with concentration, mood instability. Those symptoms are not specific to Iron deficiency. They are prominent features of mental conditions: ADHD, Bipolar Disorder or even Dementia. That , occasionally misleads physicians into making a wrong diagnosis. People with Iron deficiency may present with “unexplainable” weight loss, excessive hair shedding, “crawling” sensation under the skin, swollen legs, extreme fatigue following mild aerobic exercise or even walk in a park, feeling sleepy during the day (somnolence), and excessive need for sleep. The body requires about 30 mg of Iron daily. 28 mg is usually “recycled” inside of the body through bile re-adsorption. DMT-1 helps to absorb necessary 2 mg from the food. So, if Iron deficiency once develops, and bile re-adsorption drops bellow 28 mg, the food alone might not be sufficient to provide adequate supply of Iron to make up for the loss. Thus, when Iron deficiency develops, it has a tendency to maintain itself for a long time unless aggressively treated. Iron Deficiency (ID) can exist without anemia.
Normal hemoglobin level does not exclude Iron Deficiency. (An update on Iron physiology
Manuel Muñoz, Isabel Villar, and José Antonio García-Erce, World J Gastroenterol. 2009 Oct 7; 15(37): 4617–4626).
There are few choices of Iron available on Amazon (for example). They differ in their capacity to be adsorbed or cause side effects such as constipation:
1. Ultra-Pure Desiccated Beef Liver, Grass-Fed, Pasture-Raised Cows, made by Zen Principle (It provides small amount of Iron, and can be taken with each meal. It is usually do not cause constipation)
2. Floradix Iron & Vitamin Formula Liquid 250ml (contains vitamines)
*3. Feosol Complete Iron, 30 CountFeosol
*4. Ferrous succinate form of Iron at times causes less problems with constipation in some patients.
*5. Solgar Gentle Iron capsules feature 25 mg of iron bisglycinate, a non-constipating form of iron. There’s no gluten, wheat, or dairy.
*6. Ferrous glycinate also goes by its trademarked name, Ferrochel® is usually better adsorbed than the others and causing less constipation.
*7. Ferrous sulfate is better for patients with history stomach resection surgeries, but frequently causes constipation. Usually taken as 325 mg tablets/capsules once to three a day with orange juice or fruits, in-between the main meals. When taken with meals, it competes with Iron
from the food to be adsorbed.
To promote Iron absorption, you should be also taking:
a. Vitamin D-3 1000 IU to 2000 IU in oil capsules daily,
b. Vitamin C 250 mg to 500 mg (if not included in the accompanied iron formula),
c. One drop of iodine and a squeeze of lemon in to the glass of orange juice or water.
You can purchase Iodine solution for example on Amazon:
J.Crow’s Lugol’s Iodine Solution, 2 oz., Twin Pack (2 Bottles), by J.Crow’s
Iron supplements are best absorbed when taken with an 8-ounce glass of water on an empty stomach. Orange juice can be substituted for water (or a squeeze of lemon in your water) for enhanced iron absorption. However, iron supplements can cause stomach cramps, nausea, and diarrhea in some people. You may need to take iron with a small amount of food to avoid this problem. Milk, calcium and antacids should NOT be taken at the same time as iron supplements.
The foods that can inhibit iron absorption, like the oxalic acid in spinach, phosphates primarily in milk, other dairy products, and egg whites, phytates in beans. Certain beverages should be avoided because they can inhibit iron absorption, including: tea, coffee, milk or other calcium-rich drinks, beverages high in caffeine and tannin. Make sure, that you have at least 2 hours between taking the above products, Zinc or Calcium supplements and Iron supplement.
Dietary Sources of Iron
The table below provides the iron content per serving of some of the better food sources of iron, but it does not factor in absorption rates. For example, the absorption rate for calf’s liver is nearly 30 percent while the absorption rate for the vegetable sources is approximately 5 percent.
Food Average serving size (g) mg. iron per serving:
Calf or lamb liver 60 9.6
Beef or chicken liver 60 5.2
Beef 90 2.7
Beans cooked 100 2.3
Prunes 100 1.8
Bread (3 slices) 70 1.7
Chicken or turkey 90 1.6
Greens, cooked 75 1.5
Peas 75 1.5
Eggs 5 1.1
WARNING FOR THOSE ON THYROID HORMONE REPLACEMENT AND TAKING IRON
Be careful when adding iron to your diet if you are hypothyroid, because taking iron within four hours of taking your thyroid hormone may interfere with the absorption of your thyroid hormone and make it less effective.
Thank you for reading,
Vitaliy Shaulov, MD