What is the Role of Iron (Fe) in Good Nutrition?



What are the Key Functions of Iron (Fe)?

What are the Best Sources of Fe?

Who would benefit from Fe supplementation?

When should Fe supplementation be used?

How much Fe is usually taken?

What are the side effects of using Fe supplementation?



Haemoglobin, the pigment in red blood cells which carries oxygen, via the bloodstream, around the body, cannot be produced without iron. A shortage of the mineral will quickly show itself in breathlessness, as the heart pumps faster and the lungs try to increase the body's oxygen intake.


It is also required for the manufacture of myoglobin, a similar pigment which stores oxygen in muscles.


Fe-containing enzymes assist in the conversion of beta carotene (found in many deeply pigmented plant foods such as carrots, red peppers, apricots and spanspek) into the active form of vitamin A.


About 25 per cent of the iron in meat (heme-Fe) is absorbed by the body, whereas people may absorb less than 10 per cent of the non-heme Fe from plant sources such as vegetables, dried fruits, wholegrain bread or iron-fortified breakfast cereals.


However, more of the Fe-mineral from plant sources is absorbed if they are accompanied by food or drinks - such as peppers or orange juice - that contain vitamin C.



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What are the Key Functions of Iron (Fe)?


The mineral Fe is required for a number of vital functions, including growth, reproduction, healing, and immune function and contributes to the following important functions in the body:

  • Oxygen transport and storage
  • Electron transport and energy metabolism
  • Antioxidant and beneficial pro-oxidant functions
  • Oxygen sensing
  • DNA synthesis


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What are the Best sources of Fe


Offal, particularly liver and kidneys, is the best source of the mineral Fe, although liver should not be eaten by women who are pregnant or trying to conceive because of the danger of excessive vitamin A intake.


Fe-rich foods that can make your family's diet all the more nutritious include:

  • red meat
  • dark poultry
  • tuna
  • salmon
  • eggs
  • tofu
  • enriched grains
  • dried beans and peas
  • dried fruits
  • leafy green vegetables
  • blackstrap molasses
  • iron-fortified breakfast cereals


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Who would benefit from Fe supplementation?


Men and women have different requirements for the mineral-Fe.


Indeed, women, from the onset of monthly periods until the menopause, need almost twice as much dietary Fe as men.


A lack of adequate dietary Fe over a long period can result in Fe-deficiency anaemia; symptoms may include chronic infections of the ears, gums and skin, excessive tiredness and lack of stamina, as well as a pale complexion.


Strict vegetarians are often at risk from this type of anaemia.


Deficiency can be a problem for particularly toddlers and teens. Teen athletes lose the mineral Fe through sweating and other routes during intense exercise.


After 12 months of age, toddlers are at risk for deficiency because they no longer drink Fe-fortified formula and may not be eating Fe-fortified infant cereal or enough other Fe mineral-containing foods to make up the difference.


Toddlers drinking more than 710 milliliters every day of cow's milk can be at risk of developing deficiency because:

  • Cow's milk is low in Fe.
  • Children, especially toddlers, who drink a lot of cow's milk may be less hungry and less likely to eat iron-rich foods.
  • Milk decreases the absorption of the mineral Fe and can also irritate the lining of the intestine, causing small amounts of bleeding and the gradual loss of Fe in the stool.

If a child's experience growth problems and / or learning difficulty or show any signs of behavioural problems it could be because of Fe mineral deficiency. And it can progress to Fe-deficiency anaemia, a condition in which there's a decrease in the number of red blood cells in the body.



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When should Iron (Fe)supplementation be used?


The mineral Fe plays a key role in helping to prepare your immune system's infection fighters for battle.


Low Fe levels can also cause fatigue, pallor and listlessness-hallmarks of anemia.


In children, low Fe levels can cause stunted growth and impaired learning.


Other symptoms of Fe deficiency include split nails, a sore tongue and cold hands and feet.


An annoying condition called restless legs has also been linked to low mineral Fe.


Most experts recommend that you don't take Fe supplements unless your doctor confirms the need with a blood test.



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How much Iron is usually taken?


Recommended Dietary Allowance (RDA) for Fe (mg/day)


The RDA for mineral Fe was revised in 2001 and is based on the prevention of deficiency and maintenance of adequate Fe in individuals when eating a mixed diet.


Infants

  • 0-6 months – For Males 0.27 (AI) and Females 0.27 (AI)
  • 7-12 months - For Males 11 (AI) and Females 11 (AI)

Children

  • 1-3 years - For Males 7 (AI) and Females 7 (AI)
  • 4-8 years - For Males 10 (AI) and Females 10 (AI)
  • 9-13 years - For Males 8 (AI) and Females 8 (AI)

Adolescents

  • 14-18 years - For Males 11 (AI) and Females 15 (AI)

Adults

  • 19-50 years - For Males 8 (AI) and Females 18 (AI)
  • 51 years and older - For Males 8 (AI) and Females 8 (AI)

Pregnancy

  • All ages - For Females 27 (AI)

Breastfeeding

  • 19 years and older - For Females 9 (AI)


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What are the side effects of using Iron (Fe) supplementation?

Fe mineral poisoning is rare, possibly occurring most commonly in children who have found and eaten Fe supplements, mistaking them for sweets.


Others at risk from Fe poisoning are people with haemochromatosis, a genetically inherited disorder which affects about 3 people in every 1000.


In rare instances, the accumulation of Fe in the body over a long period causes a form of iron poisoning called siderosis. This condition can be a result of numerous repeated blood transfusions, and has also been associated with long-term regular drinking of alcoholic drinks brewed in Fe containers. Siderosis is characterized by a distinctive grayness of the skin.


If Fe toxicity is suspected, seek advice from your doctor. Neither diets nor any particular foods are known to help the problem, although some experts suggest that giving 500ml of blood weekly should help to reduce the levels of iron in the blood.



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