Iron-Deficiency

Iron and your body

Iron is an important mineral for our health. It makes up hemoglobin which is found in red blood cells and carries oxygen to different parts of the body. Iron deficiency is when iron levels are low and, if significant, can then lead to a decreased production of red blood cells (anemia).

How is it diagnosed?

Iron deficiency is diagnosed with blood testing. An “iron panel” typically checks levels of iron, percent saturation, total iron binding capacity (TIBC), and ferritin (a marker of iron stores). Iron deficiency may be suspected if there are abnormalities on a complete blood cell count (CBC) test. For example, if it shows anemia (low red blood cell count/hemoglobin levels) or small red blood cells (low MCV).

What causes it?

There are many different causes of iron deficiency. For example, menstruating women can develop iron deficiency if they have heavy periods. After bariatric surgery, without adequate iron supplementation, patients can develop iron deficiency as they do not get the necessary amount of iron from the foods they eat and, in the case of malabsorptive procedures, are not properly absorbing iron.

Symptoms

Many people with iron levels do not have any symptoms, especially if they have not developed anemia (low red blood cell count). However, at a certain point if iron levels are low enough a person may develop side effects such as strange food cravings (e.g. chewing ice, flour), fatigue, and shortness of breath.

Treatment options

Oral iron supplements

Ferrous sulfate, ferrous gluconate, and ferrous fumarate are the most common forms of iron found in supplements and may be available in liquid or pill form. Ferrous fumarate contains the most elemental iron but can be associated with more gastrointestinal symptoms (e.g. upset stomach, constipation). Iron bisglycinate may be better tolerated but can be more expensive. Do not buy enteric-coated or sustained-release capsules as these are not well absorbed. Consult with your Form Health medical clinician for specific iron supplement dosing recommendations.

Common side effects from iron include constipation and stomach upset and you may notice that it turns your stools black. To prevent constipation, consider taking a fiber supplement like psyllium (but not at the same time as your iron supplement) and drink plenty of water.

Taking iron with food or at bedtime may help prevent stomach upset, and if possible try to avoid taking with calcium-containing foods/beverages (e.g. milk) and fiber supplements which can affect its absorption.

Iron infusions

Iron can be infused intravenously (through veins) though this is not commonly done unless oral supplementation has not been effective or your levels are extremely low. This may take only one or a few sessions to restore iron levels to a normal range. Iron infusions must be prescribed and managed by a medical provider and insurance coverage varies.

Nutrition

Increasing dietary iron alone is not usually sufficient as a treatment for iron deficiency anemia (a 2,000 calorie diet typically has around 10 mg elemental iron vs. 65 mg in a tablet of ferrous sulfate). However, eating a diet high in iron-rich foods may help prevent future deficiency. Below are foods that are rich in iron.

Dietary sources of iron

Serving size 1 cup unless otherwise noted

  • Lentils: 6.6 mg
  • Chickpeas: 4.7 mg
  • Black beans: 3.6 mg
  • Soy beans: 8.8 mg
  • Spinach: 6.4 mg
  • Kidney beans: 5.2 mg
  • Dried apricots: 10 mg (1/2 cup)
  • Dried prunes: 4.5 mg (1/2 cup)
  • Tahini: 1.4 mg (2 Tbsp)
  • Eggs: 0.9 mg (1 egg)
  • Lean beef: 2.3 mg (3 ounces)
  • Clams (canned): 2.3 mg (3 ounces)
  • Wild salmon (cooked): 0.9 mg (3 ounces)
  • Tofu: 6.6 mg (1/2 cup)
  • Quinoa: 1.5 mg (1/2 cup)
  • Sardines: 2.4 mg (3 ounces)
  • Pumpkin seeds: 3 mg (1/4 cup)
  • Chia seeds: 3.3 mg (1/4 cup)

Iron absorption in foods

There are 2 different forms of iron in foods, heme and non-heme iron. Heme iron, found in animal sources of iron (e.g. meat, fish, poultry) is better absorbed by the body while non-heme iron found in plant sources of iron is harder to absorb. That is why people who follow a vegan diet may be at higher risk for developing iron deficiency. Cooking foods in a cast-iron pot/pan naturally adds iron to foods in the cooking process.

Certain components of foods can block the absorption of iron such as tannins in black tea and coffee and calcium in dairy products like milk, yogurt, or cheese. Work with your Form Health dietitian to help incorporate or avoid certain foods for best absorption.

Recommended Daily Allowance (RDA)

RDA is based on the needs of healthy individuals. Iron intake for the treatment of iron deficiency should be discussed with your Form Health medical clinician.

Iron RDA for Adults
19-50 years:
Male: 8mg
Female: 18mg
Pregnancy: 27mg
Breastfeeding: 9mg (and not having a period)

51 or older:
Male and Female: 8mg