Get premium membership and access questions with answers, video lessons as well as revision papers.
Body needs
A normal person with normal haemoglobin levels absorbs only 2-10% of dietary non-
heme iron and 23% of heme iron. Iron deficient individuals may absorb as much as a
third of dietary iron from heme and a fifth from non-heme. Need for iron is increased
with exercise because the production of red blood cells increases.
Form of iron
Ferrous iron is absorbed better than the ferric iron. Organic acids such as vitamin C
moderately increase non-heme absorption by adding an electron to ferric iron (Fe3+)
yielding ferrous iron (Fe2+). Vitamin C then forms a complex called chelate with Fe 2+
thereby enhancing absorption. As such iron supplements should be taken together
with vitamin C rich drinks such as fresh orange juice.
Composition of meal
When meat is eaten with a vegetable and grain products, the absorption of non heme
iron present is improved. A protein factor in meat, fish and poultry(MFP factor)
facilitate non heme absorption. This factor appears to contain amino acids such as
cysteine that bind iron to enhance absorption.
Acid in the stomach
Acid also plays an important role in iron absorption by promoting the conversion of
Fe3+ to Fe2+ and by solubilizing non heme iron. The decreased production of stomach
acids experienced by many elderly people can lower their iron absorption and
ultimately their body stores of iron.
Dietary factors
Several dietary factors interfere with the body’s ability to absorb iron and these
include;
- Phytic acid and oxalic acid in vegetables which bind iron thus reducing
its absorption.
- Dietary fibre intakes above 35g/day bind iron and other trace elements.
- Polyphenols such as tannins found in tea and related substances found in coffee also reduce iron absorption. People trying to rebuild iron stores are advised to reduce coffee and tea consumption, particularly meal times.
- Calcium supplements in amounts greater than 300 mg/d can reduce iron absorption. Calcium supplements should be taken several hours before or after an iron rich meal.
Titany answered the question on November 8, 2021 at 06:03
- Factors depressing calcium absorption in the human body(Solved)
Factors depressing calcium absorption in the human body
Date posted: November 8, 2021. Answers (1)
- Discuss the General functions of minerals in the Human Body(Solved)
Discuss the General functions of minerals in the Human Body
Date posted: November 8, 2021. Answers (1)
- Discuss the Functions of vitamin C in a Human's Body(Solved)
Discuss the Functions of vitamin C in a Human's Body
Date posted: November 8, 2021. Answers (1)
- Describe biotin stating its meaning, role in the body and effects of its deficiency(Solved)
Describe biotin stating its meaning, role in the body and effects of its deficiency
Date posted: November 8, 2021. Answers (1)
- Functions of pyridoxine(vitamin B6)(Solved)
Functions of pyridoxine(vitamin B6)
Date posted: November 8, 2021. Answers (1)
- Explain the Functions of folic acid(Solved)
Explain the Functions of folic acid
Date posted: November 8, 2021. Answers (1)
- List the characteristics of water soluble vitamins(Solved)
List the characteristics of water soluble vitamins
Date posted: November 8, 2021. Answers (1)
- Discuss the effects of Vitamin A Deficiency in a Human's Body(Solved)
Discuss the effects of Vitamin A Deficiency in a Human's Body
Date posted: November 8, 2021. Answers (1)
- Outline the Functions of vitamin A in Human Nutrition(Solved)
Outline the Functions of vitamin A in Human Nutrition
Date posted: November 8, 2021. Answers (1)
- List down the Characteristics of fat soluble vitamins(Solved)
List down the Characteristics of fat soluble vitamins
Date posted: November 8, 2021. Answers (1)
- List the Roles of fat in the diet(Solved)
List the Roles of fat in the diet
Date posted: November 5, 2021. Answers (1)
- List the Roles of fat in the body(Solved)
List the Roles of fat in the body
Date posted: November 5, 2021. Answers (1)
- Describe the Digestion of fats(Solved)
Describe the Digestion of fats
Date posted: November 5, 2021. Answers (1)
- Discuss the two types of Essential fatty acids (EFA)(Solved)
Discuss the two types of Essential fatty acids (EFA)
Date posted: November 5, 2021. Answers (1)
- Describe different Reaction at double bonds of fatty acids(Solved)
Describe different Reaction at double bonds of fatty acids
Date posted: November 5, 2021. Answers (1)
- Give Examples of saturated and unsaturated fatty acids(Solved)
Give Examples of saturated and unsaturated fatty acids
Date posted: November 5, 2021. Answers (1)
- Outline ways of preventing Protein Energy Malnutrition (PEM)(Solved)
Outline ways of preventing Protein Energy Malnutrition (PEM)
Date posted: November 5, 2021. Answers (1)
- What are the Clinical signs of Kwashiokor?(Solved)
What are the Clinical signs of Kwashiokor?
Date posted: November 5, 2021. Answers (1)
- What does Protein Energy Malnutrition mean?(Solved)
What does Protein Energy Malnutrition mean?
Date posted: November 5, 2021. Answers (1)
- Factors affecting protein requirements in a human body(Solved)
Factors affecting protein requirements in a human body
Date posted: November 5, 2021. Answers (1)