2019 has been declared by UNESCO as the Year of the Periodic Table. To celebrate, we are releasing a series of blogs about our favourite elements and their importance to the chemical industry. Today’s blog focuses on iron and its importance for human health.
Iron’s biological role
Iron is an important component of hemoglobin, a protein in the red blood cells which transports oxygen throughout the body. If there is a low level of iron in your body, your body will be unable to carry healthy oxygen-carrying red blood cells and a lack of these red blood cells can result in iron deficiency anemia.
During the 17th century, iron had early medicinal uses by Egyptians, Greeks, Hindus and Romanians, and around 1932, it became established that iron was essential for haemoglobin synthesis.
Red blood cells
The World Health Organisation (WHO) released figures suggesting that iron deficiency is incredibly common in humans and therefore happens to be a primary cause of anaemia.
According to their statistics, around 1.62 bn cases of anaemia are caused by iron deficiency and according to WHO’s 2008 reports, anaemia can be caused by excessive blood loss, poor iron absorption, and low dietary intake of iron.
Iron bioavailability in food is low among populations consuming plant-based diets. Iron requirement is very important, and when low levels of iron deficiency are prominent among populations in developing countries, subsequent behavioural and health consequences follow.
These include reduced fertility rates, fatigue, decreased productivity and impaired school performance among children.
During pregnancy, iron utilisation is increased as it is essential nourishment for the developing fetus. In 1997, a study proved that pregnant women needed the increase in iron, as 51% of pregnant women suffered from anaemia, which is twice as many non-pregnant women.
As iron is a redox-active transitional metal, it can form free radicals and in excessive amounts. This is dangerous as it can cause oxidative stress which could lead to tissue damage. Epidemiological studies provide evidence to show that excessive iron can be a potent risk factor associated with chronic conditions like cardiovascular and developing metabolic abnormalities.
Dietary iron is found in two basic forms. It is found from animal sources (as haem iron) or in the form of plant sources (as non-haem iron). The most bioavailable form of iron is from animal sources, and iron from plant sources are predominantly found in cereals, vegetables, pulses, beans, nuts and fruit.
However, this form of iron is affected by various factors, as the phytate and calcium can bind iron in the intestine, unfortunately reducing absorption. Vitamin C which is present in fruit and vegetables can aid the absorption of non-haem iron when it is eaten with meat.
‘The global burden of iron deficiency anaemia hasn’t changed in the past 20 years, particularly in children and women of reproductive age,’ says researcher, Dora Pereira. Although iron is an important nutrient to keeping healthy, it is imperative that iron levels are not too high.