Iron is one of the most common elements in the earth and a very essential mineral required by our body. It is the fourth most abundant element. It is classified under micro minerals and is required in more amount by our body among other elements in the same group.
It is also the most thoroughly studied mineral nutrient. It forms the most essential element for the production of blood constituting about 70% of the whole body in red blood cells called haemoglobin. Its major role is to carry oxygen in the haemoglobin of red blood cells which is then transferred from lungs to the tissues throughout the body.
Iron is also a major component of myoglobin, a protein that provides oxygen for short term storage and transportation to muscle cells. Iron is a vital element for many physiological reactions including transport of oxygen, respiration and energy metabolism, brain development and growth in children, DNA replication and repair, cellular functioning and synthesis of some hormones.
It is also a necessary component for a variety of enzymes and is needed for several additional functions like growth, reproduction, healing and proper immune function.
Types Of Dietary Iron
Iron in foods usually exists in two forms :-
It is the type of iron that comes from the animal protein in your diet and are readily absorbed by your body. It is found mostly in red meat, seafood, fish and poultry. Heme iron constitutes a large source of dietary iron for people as the human body has a higher absorption rate (about 15-35%), much higher than that of non-heme iron.
The human body absorbs around 8 per cent of the iron they consume from food. Most of the iron in the body is used to make heme. Heme is circulated and reused when blood cells are replaced with new cells every 120 days.
This type of iron is found in plant-based foods like fruits, vegetables, grains, nuts and seeds. Non-heme iron is not only limited to plant foods but also found in animal products like milk and eggs. Whereas, animal meat is a combination of both heme and non-heme.
Although non-heme iron constitutes a larger percentage in animal food, it does not comprise a large source of dietary iron as it is absorbed in a much lesser rate (about 2-10%) by the human body compared to the heme iron. Our body absorbs iron from animal-based food better than the plant-based foods.
So, people who consume a strictly vegetarian diet are more at risk of developing iron-deficiency anemia compared to people who consume meat. These people may also be required to take iron supplements.
Iron Deficiency Symptoms And Impact On Health
The most common cause of iron deficiency is the loss of blood in the body. Most of the symptoms of iron deficiency are a result of associated anaemia.
This may include extreme fatigue, weakness and dizziness, frequent heart palpitations, frequent headache and migraine symptoms, nails are sunken and easily broken. Risk of iron deficiency is more dominant on small children, infants and women who are pregnant and menstruating. For pregnant women, severe iron deficiency may increase the risk of early and abnormal birth of the baby.
Also, poor mental development of the child. The exhaustion of iron in the body can affect everything from poor brain functioning to poor immunity, difficulty in concentration. On the other hand, excess of too much iron in the body may cause vomiting, heart failure, sexual dysfunction.
Recommended Intake Of Iron
Iron deficiency is one of the most common nutritional deficiency in the U.S. According to figures from the Centers for Disease Control and Prevention, almost 10 per cent of women are deficient in iron. Women are required to have more need of iron compared to men.
They tend to lose blood every month during periods or while giving birth to a child. Hence, an adult woman from age 19 to 50 require at least 18 mg of iron per day, while men for the same age group can have just 8 mg.
Daily need of iron and other nutrients for all age groups and gender are provided in the Dietary Reference Intakes (DRIs) which determines the Recommended Dietary Allowance (RDA), an average daily level of intake sufficient to meet the nutrient requirements of nearly all healthy individuals.
Below table shows the Recommended Dietary Allowance for iron for all life stages. Age Male Female Pregnancy Lactation Birth to 6 months 0.27 mg (AI) 0.27 mg (AI) 7–12 months 11 mg 11 mg 1–3 years 7 mg 7 mg 4–8 years 10 mg 10 mg 9–13 years 8 mg 8 mg AI: Adequate Intake (It is a level that is assumed to provide enough of that nutrient.)
The iron intake can be fulfilled by eating food high in iron such as fortified cereals, red meat, dried fruit and beans. However, if your iron is still low after dietary intakes, you can take iron supplements with the consultation of your doctor.
Iron supplements are available in different forms such as ferrous sulphate, ferrous fumarate, ferrous gluconate. These are the chemical compound form as iron is bound to the salts. The actual amount of iron present in these compound is called elemental iron and this is the actual amount available in the supplement for the body to absorb. For example, a ferrous sulfate iron supplement of 325 mg will contain elemental iron of 65 mg.
So, it is always to consider the elemental iron amount as the actual intake. Different iron supplements may vary in the compound form and amount of elemental iron present in it. For example, ferrous gluconate is available in liquid form and are considered to be absorbed better than ferrous sulfate tablets.
However, ferrous gluconate contains less elemental iron (12%) than ferrous sulfate (20%). So, a greater dose of ferrous gluconate may be consumed to overcome the iron deficiency than that of ferrous sulfate. Moreover, it is more expensive than ferrous sulfate iron supplement.
Hence, it is better to consult your doctor about the form and quantity required to intake and you should always keep a check on your iron level, especially if you are in iron supplementation.
Side Effects Of Iron supplements
Although taking iron supplements may be relatively safe at the recommended dose, some immediate side effects have been reported, mostly related to gastrointestinal discomforts such as nausea, vomiting, diarrhoea, darkening of stool and constipation. Adding extra fiber to your diet can help relieve this symptom.
The maximum tolerated intake of iron is about 45 mg per day for people without medical conditions, including pregnant and breastfeeding women. Iron overdose for a shorter period may cause acute poisonings such as abdominal pain, melena, pulse, low blood pressure, fever, dyspnea, coma and other symptoms.
Safety Precautions For Iron Supplementation
Iron supplements should be taken only if the blood test shows iron deficiency or as directed by the doctor, you should not take it arbitrarily. Some people have hereditary hemochromatosis, a disease in which too much iron builds up in your body. For them, taking iron supplements may have various iron poisoning effects.
The risk of iron poisoning may increase if you consume more vitamin C rich foods in a combination with iron. Vitamin C helps your body absorb iron easily. 14–18 years 11 mg 15 mg 27 mg 10 mg 19–50 years 8 mg 18 mg 27 mg 9 mg 51+ years 8 mg 8 mg Iron supplements may also reduce the absorption of certain drugs.
On the contrary, drugs may also inhibit iron absorption. People with liver and kidney disease or special medical conditions, you should consult your doctor before taking iron supplements.
People should get iron from natural food sources. A good and planned diet will provide enough iron. It is possible to obtain enough iron in a vegetarian diet also with careful planning and in a combination of non-heme iron foods with vitamin C rich foods. The proper amount and type of iron you consume is important for your health. Below are some iron-rich foods.
Heme iron foods
Meat : Beef, Lamb, Ham, Turkey, Chicken, Veal, Pork, Dried beef, Chicken liver, Liverwurst. Seafood: Clams, Shrimp, Oysters, Scallops, Tuna, Sardines, Haddock, Mackerel.
Non-heme iron foods:
Cooked soybeans, Blackstrap molasses, Cooked lentils, Cooked Spinach, Tofu, Bagel, Cooked chickpeas, Tempeh, Lima beans, all kinds of green vegetables.
Iron is an important mineral required by our body for many functions, majorly as a component in haemoglobin which transports the oxygen from our lungs to throughout the body. It also helps in the storage and transport of oxygen in our muscle cells and constitutes as a component in various proteins and enzymes.
Our body needs the proper amount of iron as too little can cause us to develop iron deficiency anaemia and other various symptoms including fatigue, weakness, migraine etc. Iron deficiency is caused due to blood loss, especially for pregnant and menstruating women, poor diet, or an inability of our body to absorb sufficient iron from our foods.
Excess in iron can cause vomiting, heart failure and iron poisoning in case of an overdose of iron supplements. The recommended intake of iron for an adult is 18 mg per day for women and 8 mg per day for men. It is recommended to achieve optimal iron from natural sources of foods rather than supplements, unless as prescribed by a doctor.
The major source of heme iron which is readily absorbed by our body is obtained from animal foods like meat, seafood and poultry. The other form, non-heme iron majorly available in fruits, vegetables, nuts and seeds and is absorbed at much lesser rate by our body.
So, non-heme iron foods can be consumed in combination with vitamin C rich foods like broccoli, grapefruit, kiwi, melons, oranges, tomatoes, peppers etc. as vitamin C helps absorb iron from food.
Question :- What is iron-deficiency anaemia ?
Answer :- As the term suggests itself, it is anaemia caused due to lack of iron in the body. It is the condition of having less than the normal number of red blood cells or haemoglobin in the blood, resulting in diminished oxygen transport.
Question :- Who are the risk groups for iron-deficiency anaemia ?
Answer :- Infants and children between the ages of 6 months and 3 years are prone to iron deficiency. Adolescents in the growth phase have increased blood volume.
Women of childbearing age have menstrual blood loss. Pregnant and lactating women have increased iron needs. People not getting enough iron due to irregular diet or iron-deficient diet. People who donate blood frequently.
Question :- How can you prevent iron-deficiency anaemia in infants ?
Answer :- You should breastfeed your baby for the first year as cow’s milk is not recommended for first year. You should start feeding your baby after the age of 6 months with iron fortified cereals at least twice a day to boost iron intake.
After one year, do not feed your child more than 20 ounces (591 litres) of milk per day as other foods also contribute to the iron intake level.