Iron (Mineral Supplement)
Iron is necessary for the production of the protein haemoglobin which is responsible for the colour of red blood cells. Haemoglobin is responsible for transporting oxygen from the lungs to every living cell in the body. When haemoglobin is delivered to muscle tissue, it is converted to myoglobin which plays a role in the storage of oxygen in the muscles, particularly the heart, until it is required to oxidise glucose for the generation of energy. This allows the muscles to work efficiently and to recover quickly after exertion. The average human contains approximately 4 grams of iron, 75% of it incorporated in haemoglobin, and much of it is recycled by the body when the blood cells die.
Iron deficiency is the most common nutritional deficiency. Signs include pale skin, fatigue, dizziness and loss of concentration due to the body struggling to deliver oxygen around the body. Sores in and around the mouth and a deterioration in the condition of hair and nails may also be features. Chronic iron deficiency leads to anaemia which can cause a rapid or irregular heartbeat, pregnancy complications, and delayed growth in children.
Women who experience heavy periods may be prone to anaemia, as are people who suffer from chronic gastrointestinal bleeding or those who are receiving kidney dialysis. Prolonged use of certain antacids and drugs may also deplete iron from the body. Infants may require iron supplementation if they are bottle-fed with cow’s milk. Phytates, substances found in most plant foods, can reduce iron absorption by up to 80%, although Vitamin C can help counteract this effect. The tannins in tea and coffee can also reduce iron absorption by up to 60%.
The European Food Safety Authority recommends an intake of 11mg of iron per day for men, 13mg/day for teenage girls rising to 16mg/day until menopause, then 11mg/day post-menopause. The richest food sources of iron include red meat (particularly liver) as well as leafy dark green vegetables, pulses, blackstrap molasses and herbs such as nettle. Some foods, such as bread and breakfast cereals, are fortified with iron. Animal sources (haem iron) have a higher bioavailability – i.e. they are more easily utilised by the body – than vegetable sources (non-haem iron).
Excessive iron supplementation can lead to chronic constipation, digestive upsets and cardiac arrhythmias.
NB You should seek professional advice before taking mineral supplements.