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Everything You Need To Know About Iron
The body requires iron to make hemoglobin for blood and myoglobin for muscles.
Each of these proteins uses iron to supply oxygen and energy for everyday needs.
Iron in excess of daily needs is stored in ferritin molecules.
Iron is also involved in gene regulation, cell growth and differentiation, enzyme reactions, neurotransmitter and protein synthesis.
Normally, dietary intake offsets daily iron loss (about 1 to 1.5 milligrams per day). Therefore, one gram of storage iron (1,000 milligrams) is usually adequate to meet all foreseeable needs.
Most body iron (2.6g of 3–4 g) circulates as haemoglobin (Hb), which is recycled after red cells age and die..
One gram is stored in the liver, and 0.4 g in myoglobin and cytochromes. Small amounts (3 mg) circulate bound to plasma transferrin.
Men and non-menstruating women lose about 1 mg of body iron per day; menstruating women may lose an additional 1 mg daily on average.
Requirements for iron escalate rapidly during adolescence, the onset of menstruation in females, and in pregnancy.
Iron lost through unknown causes can signal disease processes that often lead to anemia.
Most harmful bacteria, fungi, parasites, viruses and cancers need iron to grow. Iron deficiency can sometimes indicate these pathogens have successfully invaded your body.
The diagnosis and management of iron deficiency anaemia (IDA) remains a challenge.
It is an important public health problem in Australia, with estimated 8% of preschool children, 12% of pregnant women and 15% of non-pregnant women of reproductive age in Australia have anaemia.
Symptoms of Iron Deficiency
- Dizziness
- Headache
- Shortness of breath or chest pain
- Unexplained fatigue or lack of energy
- Rapid heart beat
- Pounding or “whooshing” in the ears
- Hair loss
- Restless leg syndrome
- Flattened, brittle nails (spoon nail)
- Glossitis- inflammation of the tongue
- Angular stomatitis (cracks at mouth corners)
- Blue sclera (whites of eyes)
- Pale skin or conjunctivae
- Craving for ice or clay – pica
Causes and Risk Factors for Iron Deficiency
- Vegetarians and vegans, and other people whose diets do not include iron-rich foods
- Frequent dieting or restricted eating
- Heavy/lengthy menstrual periods
- Rapid growth
- Pregnancy or breastfeeding (current or recent)
- Gastrointestinal disease such as Coeliac disease, Inflammatory bowel disease, Diverticulitis
- Blood loss from the gastrointestinal tract or form chronic nose bleeds
- Chronic use of antacid drugs, anti cholesterol medications, aspirin or nonsteroidal anti- inflammatory drugs (e.g., ibuprofen), PPI’s, antibiotics, contraceptive pill, or corticosteroids
- Intensive physical training
- Frequent blood donations
- Parasitic infection
- Major surgery or physical trauma
- Substance abuse
Children who drink more than 473mL – 709mL (16 to 24 ounces) a day of cow’s milk are at risk of developing iron deficiency as well. Cow’s milk not only contains little iron, but it can also decrease absorption of iron and can also irritate the intestinal lining and possibly cause micro heamorrhages.
Intravascular hemolysis, a condition in which red blood cells break down in the blood stream, releasing iron that is then lost in the urine. This sometimes occurs in people who engage in vigorous exercise, particularly jogging. This can cause trauma to small blood vessels in the feet, so called “march hematuria.” Intravascular hemolysis can also be seen in other conditions including damaged heart valves.
Potential Consequences of Iron Deficiency
- Decreased maximum aerobic capacity
- Decreased athletic performance
- Lowered endurance
- Decreased work capacity
- Impaired temperature regulation
- Depressed immune function and increased rates of infection
- Impaired cognitive functioning and memory
- Compromised growth and development
- Increased lead and cadmium absorption
Iron is an important cofactor in the synthesis of specific neurotransmitters. Deficiency has been shown to reduce the expression of dopamine receptors and transporters and may be linked to depression.
With iron deficiency there is also an increased risk of pregnancy complications, including prematurity and fetal growth retardation.
How Iron Deficiency Is Diagnosed
Iron deficiency without anemia can occur when a person has a normal hemoglobin, but below normal serum ferritin and/or transferrin saturation.
Iron deficiency with anemia can occur when a person has low values of both serum ferritin and hemoglobin.
The tests used most often to detect iron deficiency include:
- Haemoglobin
Most of the body’s iron (about 60%) is contained in hemoglobin, which is the essential oxygen carrying protein of the blood.
Low or high measures of hemoglobin are not good indications of either iron overload or iron deficiency.
Hemoglobin is frequently part of a complete blood count (CBC), which is most useful in assessing general health status and to screen for and monitor a variety of disorders, such as anaemia.
- Haematocrit which provides the percentage measures of of red blood cells in the blood
- Serum Ferritin indicates the amount of iron stored in the body.
This is a very important test because it helps distinguish between iron deficiency anemia and anemia of chronic disease (also called anemia of inflammatory response). In cases of iron deficiency anemia, iron supplements can be helpful; but in cases of anemia of chronic disease, iron supplements could be harmful.
- Serum iron
Iron contained in blood serum (or plasma) is normally bound to the protein transferrin. Each molecule of transferrin can transport two molecules of iron to areas of the body that need this element.
Serum iron levels should not be used to diagnose iron deficiency.
- Ferritin is the most sensitive test to detect iron deficiency.
It is the main storage form of iron in the body. Decrease serum ferritin levels parallel a tissue ferritin level, which in turn reflects the low iron storage found in iron deficiency anaemia, or changes in red blood cells. This is because the body will do whatever it takes to keep the serum levels of iron at an optimal level.
- Transferrin Saturation
The body makes transferrin based on iron needs. Generally about one-third of transferrin is used to bind and transport iron.
Anaemia is the last stage of iron deficiency. Iron-dependant enzymes involved in energy production and metabolism are the first to be affected by low iron levels.
The group most likely to be at risk are infants under 2 years of age, teenage girls, pregnant women, and the elderly.
Other tests that might be done if iron deficiency is suspected are: testing for blood in the stool (fecal occult blood test), looking for abnormalities in the gastrointestinal tract, testing the urine for blood or haemoglobin, gyneecologic evaluation that may include a pelvic ultrasound or uterine biopsy.
Copper controls a number of enzymatic reactions that regulate iron levels and red blood cell formation. Copper deficiency can mimic many of the signs of iron deficiency anemia, even if iron levels are normal.
You can have your Iron Studies done with Emed. Please, click here to find more about the test.
What Can Inhibit Your Iron Absorption
- Excessive intake of phytates (found in legumes, grains, and rice )
- Calcium rich foods
- Tea (tannic acid)
- Polyphenols, found in some fruits, vegetables, coffee, tea, wines, and spices
- Soy protein
- Soft drinks
- Certain medications
Disease conditions can also limit iron absorption; this can happen as a result of insufficient stomach acid, lack of intrinsic factor (hormone needed to absorb vitamin B12), celiac disease, inflammatory conditions such as Crohn’s disease, and in autoimmune diseases and hormone imbalances.
Iron Sources and Repletion Strategies
Before taking supplements to correct iron deficiency, you need to determine what is the underlying cause.
Although more than 100 preparations containing iron are available over the counter in Australia, few contain sufficient elemental iron to correct iron deficiency.
Multivitamin-mineral supplements should not be used to treat iron deficiency anaemia as iron content is low and absorption may be reduced.
Women in the second an third trimester of pregnancy with iron deficiency might require intravenous iron.
Do not self prescribe iron tablets before being diagnosed with iron deficiency through a blood test, as there is a risk of iron overload and toxicity.
Long term high dose iron supplementation may lead to Copper and Zinc deficiencies. Make sure you monitor these with your healthcare practitioner.
Dietary iron comprises heme (animal sources) and non-heme iron.
Because it is absorbed by a different mechanism than nonheme iron, heme iron is more readily absorbed and its absorption is less affected by other dietary factors.
Dietary iron sources include meat, liver, fish, oysters,chicken (dark meat), tofu, beetroot, spinach lentils, dried beans, cereal, and molasses.
Hemagenics provides a unique form of chelated iron, iron bis-glycinate and is formulated for maximum absorption.
Make sure you separate your iron tabletsfrom tea, coffee, milk, soft drinks and wine, or prescription medications (antacids, antibiotics) by at least two hours (4 hours is the best).
Bioavailability of iron can be significantly improved with vitamin C, raw vegetables, lemon juice, or Apple Cider Vinegar.
Other nutrients such as vitamin B12, folate or zinc can facilitate sufficient non-heme iron absorption as well.
Take your iron supplement either on empty stomach or with meat meal.
Further reading:
References:
Oti-Boateng P, Seshadri R, Petrick S, et al. Iron status and dietary iron intake of 6–24-month-old children in Adelaide. J Paediatr Child Health 1998; 34: 250-253
Ganz T 2011 Hepcidin and iron regulation, 10 years later. Blood, 117: 4425–4433. doi: 10.1182/blood-2011-01-258467
Reeves and L De Mars, 2004, Copper Deficiency Reduces Iron Absorption and Biological Half-Life in Male Rats, The Journal Of Nutrition, http://jn.nutrition.org/content/134/8/1953.full
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