106 The nutrition handbook for food processors globin, the red pigment of blood and myoglobin in muscle, iron atoms combine reversibly with oxygen to act as its carrier from the lungs to the tissues. In a variety of enzymes, such as the cytochromes, iron atoms, present in the ferrous and ferric states, interchange with gain or loss of an electron, as part of the elec tron chain responsible for the redox reactions necessary for release of energy in cellular catabolism and the synthesis of large molecules(Brock et al, 1994) In addition to its major functions in oxygen transport and as a cofactor in many A.ymes, iron also plays an important role in the immune system. Although the chanisms involved are complex, there is good evidence that an abnormal iron nutritional status can lead to impaired immune function, with serious conse- quences for health(Walter et al, 1997) 4.6.3 Iron deficiency anaemia Iron deficiency ultimately results in failure of the body to produce new blood cells to replace those that are constantly being destroyed at the end of their normal 120-day life span. Gradually the number of blood cells falls and, with this, the amount of haemoglobin in the blood. The cells become paler in colour and smaller in size. These undersized cells are unable to carry sufficient oxygen to meet the needs of tissues, so energy release is hindered. This is what is known technically as microcytic hypochromic anaemia, or, simply, as iron deficiency anaemia(IDA) Expert Scientific Working Group, 1985). Because the fall in red blood cells occurs gradually, IDA can exist for a considerable time before it is clearly detected. By then iron stores have suffered a critical fall and the person affected shows symptoms of chronic tiredness, persistent headache, and, in many cases, a rapid heart rate on exertion. There may also be other functional consequences of iron deficiency, including a decreased work capacity, a fall in intellectual per- formance, and a reduction in immune function( Brock and mulero, 2000). There is today growing concern at the possibility that iron deficiency in infancy and childhood can have serious consequences, such as morbidity in the newborn, defects in growth and development of infants and impaired educational perfor- mance in schoolchildren(Cook, 1999) 4.6.4 Recommended intakes The UK RNI is 1.7-8. 7 mg/day for both males and females from birth to 10 years of age. This rises to 14.8 mg/day for females from 1l to 50 years, when it is reduced to 8.7 for the post-child bearing years. Women with a high menstrual loss are recommended to increase their iron intake by taking a supplement. The RNI for males from 11 to 18 years is set at 11.3 mg/day, with a drop to 8.7 mg/day for later years(Department of Health, 1991). The UK recommendations are similar to those published in the US(National Research Council, 1989), but lower than those of WHO. They are also less than recommendations in many developing countries. In Indonesia, for instance, an intake of 14-26mg/day is recommended for women of child-bearing age, withglobin, the red pigment of blood and myoglobin in muscle, iron atoms combine reversibly with oxygen to act as its carrier from the lungs to the tissues. In a variety of enzymes, such as the cytochromes, iron atoms, present in the ferrous and ferric states, interchange with gain or loss of an electron, as part of the elec￾tron chain responsible for the redox reactions necessary for release of energy in cellular catabolism and the synthesis of large molecules (Brock et al, 1994). In addition to its major functions in oxygen transport and as a cofactor in many enzymes, iron also plays an important role in the immune system. Although the mechanisms involved are complex, there is good evidence that an abnormal iron nutritional status can lead to impaired immune function, with serious conse￾quences for health (Walter et al, 1997). 4.6.3 Iron deficiency anaemia Iron deficiency ultimately results in failure of the body to produce new blood cells to replace those that are constantly being destroyed at the end of their normal 120-day life span. Gradually the number of blood cells falls and, with this, the amount of haemoglobin in the blood. The cells become paler in colour and smaller in size. These undersized cells are unable to carry sufficient oxygen to meet the needs of tissues, so energy release is hindered. This is what is known technically as microcytic hypochromic anaemia, or, simply, as iron deficiency anaemia (IDA) (Expert Scientific Working Group, 1985). Because the fall in red blood cells occurs gradually, IDA can exist for a considerable time before it is clearly detected. By then iron stores have suffered a critical fall and the person affected shows symptoms of chronic tiredness, persistent headache, and, in many cases, a rapid heart rate on exertion. There may also be other functional consequences of iron deficiency, including a decreased work capacity, a fall in intellectual per￾formance, and a reduction in immune function (Brock and Mulero, 2000). There is today growing concern at the possibility that iron deficiency in infancy and childhood can have serious consequences, such as morbidity in the newborn, defects in growth and development of infants and impaired educational perfor￾mance in schoolchildren (Cook, 1999). 4.6.4 Recommended intakes The UK RNI is 1.7–8.7 mg/day for both males and females from birth to 10 years of age. This rises to 14.8 mg/day for females from 11 to 50 years, when it is reduced to 8.7 for the post-child bearing years. Women with a high menstrual loss are recommended to increase their iron intake by taking a supplement. The RNI for males from 11 to 18 years is set at 11.3 mg/day, with a drop to 8.7 mg/day for later years (Department of Health, 1991). The UK recommendations are similar to those published in the US (National Research Council, 1989), but lower than those of WHO. They are also less than recommendations in many developing countries. In Indonesia, for instance, an intake of 14–26 mg/day is recommended for women of child-bearing age, with 106 The nutrition handbook for food processors