The Bread and Iron Problem
A 14-year-old girl in a rural area eats mainly white bread, rice and tea. She rarely eats meat, eggs, beans or green vegetables. She feels tired, is short of breath on stairs, and her teacher notices she is pale. A blood test shows low haemoglobin and small, pale red blood cells. Her family cannot afford supplements. A health worker suggests adding dark green leafy vegetables, beans and a little citrus fruit to her meals, and drinking tea between meals rather than with food.
1. Explain why her diet could cause her symptoms, naming the nutrient involved and its role.
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Her diet is low in iron. Iron is needed to make haemoglobin, the red pigment in red blood cells that carries oxygen. With too little iron, the bone marrow cannot make enough haemoglobin, so red blood cells are small and pale (microcytic, hypochromic) and the blood's oxygen-carrying capacity falls. Tissues receive less oxygen, so cellular respiration is reduced and less energy is released. This explains the tiredness and breathlessness on exertion, because the body cannot increase oxygen delivery enough during exercise. Pallor occurs because the skin has fewer oxygenated red cells. Tea also contains tannins that bind iron and reduce its absorption, and the diet lacks vitamin C, which normally boosts absorption of plant (non-haem) iron. The result is iron-deficiency anaemia.
2. Assess the health worker's advice. Which parts are sound and which need caution?
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The advice is largely sound. Dark green leafy vegetables and beans provide non-haem iron, and citrus fruit provides vitamin C, which converts iron to a more absorbable form and can increase absorption several-fold. Drinking tea between meals rather than with food is sensible because tannins in tea reduce iron absorption when taken with a meal. The caution is that plant iron is absorbed less efficiently than the haem iron in meat, so the family must eat these foods regularly and in adequate amounts, and the girl may still need a supplement or fortified food. Also, beans and greens should be cooked, and some greens contain oxalates that bind iron. The advice will help but may not fully correct an established deficiency, so her haemoglobin should be rechecked and medical treatment sought if it does not improve.
3. A neighbour says she should simply eat more white bread because it is 'fortified'. Evaluate this claim.
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The claim is only partly true and does not solve the problem. Many white flours are fortified with iron, but the amount added is modest and the iron is non-haem, so absorption is limited. Bread also contains phytates, which bind iron and further reduce absorption. Eating more bread adds energy and carbohydrate but not enough well-absorbed iron to correct anaemia, and it may displace the beans, greens and fruit that would help. A better answer is a varied diet combining iron-rich foods with vitamin C, avoiding tea at meals, and, where possible, iron-fortified foods or supplements prescribed by a health worker. So the neighbour's advice is not wrong in principle but is inadequate and could delay proper treatment.