Iron Deficiency: What is It?
We hear a lot about iron deficiency and iron deficiency anemia but what exactly are these two conditions and are they the same? Well, iron deficiency can lead to iron deficiency anemia, but one can be iron deficient without having iron deficiency anemia. The symptoms from low iron can be subtle and you can be deficient in this important mineral and not know it.
Iron is a key component of hemoglobin. Hemoglobin is a protein in red blood cells that transports oxygen. If you are deficient in iron you will make less hemoglobin, and thus carry less oxygen in the blood. And, many symptoms of iron deficiency are related to this decrease in oxygen delivery to organs and tissues.
As mentioned one can be iron deficient without being anemic. This occurs when iron stores are low but not low enough to impact hemoglobin production. Such iron deficiency without being anemic is not uncommon among female athletes.
Causes of Iron Deficiency
There are three main causes of iron deficiency.
A loss of blood usually from the gastrointestinal tract or from heavy menstrual bleeding is the most common cause of iron deficiency. Gastrointestinal bleeding can occur from peptic ulcers, colon polyps and colon cancer, and from use of aspirin and non-steroidal anti-inflammatory medications (NSAIDs) like ibuprofen. In fact, NSAIDS are responsible for 107,000 hospitalizations per year for GI bleeding and cause over 16,500 deaths a year from GI bleeding – equal to the number of people who die from AIDS in the United States annually.
Too little iron in the diet
Not getting enough iron in the diet is another way to become iron deficient. Iron rich foods include red meats, eggs, poultry, pork, seafood, beans, peas, leafy green vegetables, foods fortified with iron. Vegetarians are at risk of iron deficiency and most be sure to eat non-meat foods high in iron.
Inability to absorb iron
Disorders of the GI tract can lead to malabsorption syndromes including the inability to absorb iron. Celiac disease is relatively common and can lead to iron deficiency. Weight loss surgery (bariatric surgery) can lead to iron deficiency as well and is becoming a more common cause of iron deficiency as bariatric surgery is being increasingly performed.
Group at Risk for Iron Deficiency
Though not a disease pregnancy increases the need for more iron in the diet and can be associated with iron deficiency if that increased iron need is not met.
Female athletes are at risk for iron deficiency usually with or without being anemic. Iron deficiency is the result of iron loss from menstruation coupled with increase demand for iron because of intense athletic training. Iron deficiency in female athletes may be as high as 50%. Low iron in athletes can significantly impair athletic performance and many women notice a big improvement with endurance once they restore their iron levels.
For reasons already stated.
People who donate blood frequently are potentially at risk for developing iron deficiency.
Symptoms of Iron Deficiency
Symptoms of low iron can be subtle and tend to be unmasked when the heart is challenged to deliver more blood as in exercise or has to work harder as in heart failure patients. The more common symptoms include:
- general fatigue
- feeling weak
- pale skin
- feeling dizzy or light headed
- short of breath especially with exertion (dyspnea on exertion)
- brittle nails
- cold hands and feet
- cravings for non food items like dirt, clay, and ice.
- fast heart rate
How is Low Iron Diagnosed?
Blood tests are done to diagnosed iron deficiency anemia. These include a hemoglobin level, hematocrit, ferritin, red blood cell count and red blood cell indices (MCV, MCH, MCHC).
Hemoglobin: A normal hemoglobin ranges 13.5 g/dl to 17.5 g/dl in men and 12.5 g/dl to 15.5 g/dl in women.
Hematocrit: Hematocrit is the percentage of the blood volume made up of red blood cells. Blood also contains white blood cells, platelets, and plasma that make up the rest of the blood volume. A normal hematocrit is 39% to 50% in men and 35% to 45% in women.
As you can see the range is fairly broad. Smokers and those living at altitude can have hemoglobin and hematocrit levels above the upper end of these reference ranges. In these cases the higher levels represent a physiologic adaptation to improve oxygen delivery to the tissues.
Ferritin: Ferritin is a protein and storage form of iron. When it is low iron levels are usually low. Female athletes many times have low ferritin levels yet may have normal hemoglobin and hematocrit levels. Low ferritin alone represents an early stage of iron deficiency.
Red blood cell indices: MCV tells us about the average size of a person’s red blood cells. MCH tells us about the hemoglobin amount per red blood cell. MCHC tells us about the amount of hemoglobin relative to the size of the cell. In iron deficiency anemia the red blood cells are smaller and have lesser amounts of hemoglobin per red blood cell.
Treatment of Iron Deficiency
Once it is determined that one is iron deficient then the cause of it must be determined. Many times this can be determined by the patient’s history including a nutritional history/evaluation. If gastrointestinal bleeding is suspected than endoscopy procedures are performed.
This may be a colonoscopy looking for a lower GI or colon source of bleeding and/or an upper endoscopy to evaluate the esophagus and stomach for a bleeding source. In women with heavy menstrual bleeding an ultrasound or CT scan of the pelvis may be done to look for abnormalities of the uterus. If bleeding is found then the appropriate procedure/surgery is performed to remove or stop the bleeding source.
Treatment includes incorporating more iron rich foods tot the diet. Iron supplements may be recommended or prescribed. Vitamin C improves the absorptions of iron so taking iron supplements with orange juice is many times recommended. On the flip side, antacids will hinder the absorption of iron. Iron supplements can lead to constipation usually easily managed with use of stool softeners.
Iron supplements and dietary changes may not be enough for those with malabsorption problems (since they cannot enough absorb iron from the gut) and especially those who have had bariatric surgery. In those individuals it may be necessary to have periodic IV infusions of iron.
In those severely anemic blood transfusions are performed.
Iron deficiency does not correct overnight and can take several weeks and months to totally correct. But many feel substantially better once their iron levels improve even slightly.
If you want to compete and win a iron man (woman) competition, you’ll want to be sure you are not deficient in iron.