Iron: benefits, foods, uses, daily dosage & side effects

A major portion of the iron is present in our body inside RBCs, as heme protein, haemoglobin. Each haemoglobin molecule has about 4 iron centres with a protein chain and single haemoglobin can thus bind to about 4 oxygen molecules.

A different compound present in muscles and which helps in storage and absorption of iron in the muscle tissue is myoglobin, though, it contains only one iron molecule each. Together, these proteins ensure that oxygen travels from your lungs to your body organs via blood.

Reduction in haemoglobin, iron or RBCs would thus lead to anaemia which is manifested in the form of symptoms such as fatigue, exhaustion, headache, shortness of breath, nausea and discolouration of the oral mucosa.

Haemoglobin production and oxygen transport may be the first and most important function of iron in our body. But, it has various other functions that are needed to maintain cellular metabolism including energy generation and DNA repair. Bet you never thought your daily green veggies or pulses are so important to your body cells. Iron is converted to FE-S clusters and stored as ferritin in the body. These FE-S clusters aid in the regulation of enzyme, protein function and expression of genes. By helping maintain and regulate DNA synthesis and repair, iron helps you age gracefully.

Iron has a central role in hair growth since it is important for carrying out the various processes inside the hair follicle. Quite obviously, a deficiency in iron would negatively affect hair growth. Research evidence indicates that low levels of ferritin (> or equal to 30 ng/ml) can increase hair loss in women which is independent of any inflammation or skin condition. In a recent study, lack of iron was found to be the cause of female pattern hair loss, especially in premenopausal women.  This may be because premenopausal women lose some of the iron during menstruation every month.

According to a case study mentioned in the Annals of Dermatology, ferrous sulphate was found to be useful for reverting premature hair greying in an Asian male in his 20s.

So, it is important to take the daily dose of iron and keep your hair looking longer and healthier.

Iron deficiency and anaemia are two of the most feared conditions during pregnancy. Low haemoglobin levels in a gestating woman may remain asymptomatic for long but can adversely affect foetal growth and birthweight. This is because a pregnant woman needs about 1000 to 1200 mg of iron per day. About ⅓ of this is maternal demand and rest is needed for foetal growth and haematopoiesis (formation of blood). The demand for iron increases progressively from first to the third trimester, however, a deficiency in the first trimester is most often the cause of birth defects as iron is needed for the formation of the neural tube.

Babies born to an anaemic mother may also show signs of anaemia and have been found to exhibit lowered memory and cognition even in the later stages of life. Despite this, foetal defects and miscarriage were found to be only caused when blood haemoglobin levels fall down below 10g and it is not important to take iron supplements if your haemoglobin levels are normal.

It is suggested that you refer to a doctor to know if you need iron supplements in the first place.

Just like an iron deficiency causes impairment in neonatal brain functions, it can lead to memory defects and reduced cognition in adults and older children too. This is because iron is required to produce energy via various cellular processes and this energy is needed to maintain and regulate neuron function and structure. Important functions of iron in the brain include:

• DNA synthesis
• Myelin synthesis
• Synthesis of various neurotransmitters

Any imbalance in iron levels leads to the formation of harmful hydroxyl radicals which in turn increases the oxidative stress and speeds up the ageing process in the brain. Improper iron distribution and accumulation is one of the diagnostic features of neurodegenerative diseases such as Alzheimer's and Parkinson’s.

It is important that you don’t miss out on your dietary iron to keep your brain healthy and reduce the risk of neurodegeneration.

(Read more: How to improve brain power)

Iron is important to carry out various cellular functions in humans but they are as important to microbial cells and hence, there is a constant tug of war between host cells and pathogenic bacteria to obtain iron. This also forms one of the major factors of immunity and host defence or alternatively, infections.

Human body maintains constant homeostasis of iron to perform its everyday functions and to avoid excess.

Iron is preserved inside the haemoglobin ring to keep infectious microbes from reaching in and these microbes, in turn, target and lyse RBCs or compete with normal body proteins which scavenge off these lysed heme protein molecules.

On the other side, iron is needed to mediate a proper immune response by the host body.

• Iron is responsible for mediating cytokine production (a type of immune system protein) in macrophages.
• Lactoferrin is yet another iron compound released by neutrophils to fight infection.
• Iron is used by the immune system to inhibit microbial growth since it also has some toxic effects on living cells.

Iron overload is further responsible for increased oxidative stress which degrades metabolism, and leads to a weaker immune system, thus leading to an increased chance of acquiring infections.

Needless to say, it is important that you maintain a healthy balance of iron in your body by not taking excessive supplements until needed.

(Read more: How to improve immunity)