Iron, a trace element, is found in the human body at a concentration of 50-60 mg per kilogram of body weight; resulting in about 3 to 5 g of iron present in the body. Around 70% of iron in the body is a part of the hemoglobin (red blood cells), 10% is part of the body’s enzymes and the remaining 20% of the iron is stored in the liver and spleen.
Iron is found in foods of animal and plant origin. Food contribution to the body’s iron level depends less on the iron content, but more on the availability of iron – also from what is coming into the body from inhibitory or stimulating substances. The iron absorption rate from foods of animal origin is 20-30% and from foods of plant origin is 1-10%. Vegetarians don’t need to be concerned about any iron deficiencies, when they are clearly aware of the stimulating and eventually the inhibitory factors (interactions).
Functions in the Body
- Transport of oxygen in the blood
- Oxygen storage in the muscles
- Iron is a component of several enzymes
- Reduced physical performance
- Susceptibility to infection
- Malaise, fatigue and exhaustion
- Growth disorders in hair and nails
High iron content in the body mainly occurs in people with a genetic disorder that leads to excessive iron intake. Too much iron in the blood disrupts copper and zinc metabolism, damages intestinal mucosa and causes kidney and liver damage. High doses of iron supplements can cause damage, too. Symptoms include nausea, vomiting, upper abdominal pain accompanied by diarrhoea or constipation, as well as blood clotting disorders.
+ The iron absorption rate is increased by the simultaneous intake of vitamin C, fruit acids and other organic acids, such as tartaric acid or lactic acid.
– Plant food ingredients such as oxalate (especially in rhubarb, spinach and Swiss chard), phytic acid (such as in legumes and whole grains), tannins and other polyphenols (see under phytochemicals) inhibit iron absorption, as well as chrome, phosphate and/or dietary fibres. Calcium in milk and caffeine in coffee also reduce iron intake.
Meat, nuts, poultry, fish, legumes, walnuts and seeds, whole milk products and green vegetables.
Recommended Daily Amounts
Young people 12 mg / 15 mg
Adults 10 mg / 15 mg
Adults 65 years old and over 10 mg / 10 mg
«5 a Day» helps you in meeting your body’s daily mineral and trace elements requirements.
The body’s daily requirement of 12 mg of iron is contained 185 g of chanterelle mushrooms, or 360 g of salsify, or 440 g of spinach, or 520 g of Swiss chard, or 570 g of lamb’s lettuce, or 600 g of sugar peas, or 630 g peas, or 750 g of elderberries, or 1 kg of red currants or mango.