Iron

Figure 1. The crystal structure of Iron.

Iron is a chemical element with symbol Fe and atomic number 26. Iron is an essential nutrient and play essential roles in vertebrate metabolism including oxygen transportation in blood and oxygen storage in muscles. Iron also plays a role in cellular respiration, oxidation, and reduction in plants and animals.

The body of an adult human contains about 4g of Iron, found mostly in hemoglobin and myoglobin, proteins found in red blood cells and muscle tissues of vertebrates. Iron is necessary for physical growth, neurological development, cellular functioning, and synthesis of some hormones.

Iron in nature exists in two forms. Heme iron: a form of iron that is found in animal-derived foods and is more readily absorbed by the human body; and Non-heme iron: a form of iron that is found in plant-based and iron-fortified foods and is not as well absorbed as heme iron.

Food Sources

Iron can be found in a wide variety of foods. The richest sources of Iron in the diet include lean meat and seafood.

• Cereals
• Oysters
• White beans
• Beef liver
• Lentils
• Spinach
• Tofu
• Dark Chocolate
• Kidney beans
• Sardines
• Chickpeas
• Tomatoes
• Beef
• Potato
• Cashew Nuts
• Green Peas
• Chicken
• Rice
• Whole Wheat Bread
• White Bread
• Raisins
• Spaghetti
• Tuna
• Turkey
• Pistachio Nuts
• Broccoli
• Eggs
• Cheese
• Cantaloupe
• Mushrooms
• Milk

Taken as a Dietary Supplement

Iron is available in many dietary supplements. Frequently used forms of iron in supplements include ferrous and ferric iron salts, such as ferrous sulfate, ferrous gluconate, ferric citrate, and ferric sulfate. Iron supplements are primarily taken to help with iron deficiency conditions, such as anaemia.

Iron deficiency is common especially among young children, women of reproductive age, and pregnant women. Because iron deficiency is typically associated with poor diets, malabsorptive disorders, and blood loss, people with iron deficiency usually have other nutrient deficiencies as well. Although iron deficiency is the most common cause of anaemia, deficiencies of other micronutrients (such as folate and vitamin B12) and other factors (such as chronic infection and inflammation) can cause different forms of anaemia or contribute to their severity. Effects may include gastrointestinal disturbances; weakness; fatigue; difficulty concentrating; and impaired cognitive function, immune function, exercise or work performance, and body temperature regulation. In infants and children, Iron deficiency may result in psychomotor and cognitive abnormalities that, without treatment, can lead to learning difficulties.

The recommended daily allowance of Iron is:

• 0.27mg for infants (up to 6 months old)
• 11mg for babies 7-12 months old
• 7mg for children 1-3 years old
• 10mg for children 4-8 years old  
• 8mg for children 9-13 years old
• 11-15mg for children 14-18 years old
• 8-18mg for adults 19-50 years old (27mg for pregnant women)
• 8mg for adults 51+ years old