Minerals Overview

Question 1

Minerals

Answer 1

• Minerals are inorganic elements that originate in the Earth and cannot be made by living organisms.
• For humans to absorb and use minerals they must first be bound to organic compounds (containing carbon)
• Plants obtain minerals from the soil and most of the minerals in our diet come directly from plants (or indirectly from animal sources)
• Inorganic minerals may also be present in the water we drink (not useable by the body).
• Mineral levels from plants also vary depending on the mineral content in soil.

Question 2

Minerals and the body

Answer 2

• Minerals represent 4- 5% of total body weight.
• The body uses minerals to perform many different functions. Minerals are found in all body tissues.
• Calcium and Phosphorus make up the majority (approx. 75%).

Question 3

Macro- minerals

Answer 3

Calcium (CA)
Phosphorus (P)
Magesium (MG
Potassium (K)
Sodium (Na)
Chloride (Cl)
Sulphur (S)

Question 4

Trace- Minerals

Answer 4

Iron (Fe)
Zinc (Zn)
Iodine (I)
Selenium (Se)
Manganese (Mn)
Molybdenum (Mo)
Copper (Cu)
Chromium (Cr)
Boron (B)
Fluoride (F)
Silicon (Si)

Question 5

Cations

Answer 5

• Cations: K (Potassium), Mg 2+ (Magnesium), Ca 2+ (Calcium), Na+ (Sodium)

Question 6

Anions

Answer 6

Cl^- (Chlorine as Cloride)

S^- (Sulphur as sulphate);

P^- (Phosphorus as phosphate)

Question 7

Mineral Absorption and Functions

Answer 7

• Minerals are absorbed in the GIT (mostly in the small intestine ) in their ionic state (with the exception of iron) and must be unbound from the organic compound with the help of digestive secretions (e.g. stomach acid) before being utilised by the body
• Any unabsorbed minerals are excreted in the faeces.
• Key functions of minerals include:
- Building tissues; e.g. skeletal system, teeth
- Nerve and muscle function
- Thyroid health (supporting metabolism)
- Supporting immune health
- Components of enzymes

Question 8

Minerals and bioavailability

Answer 8

1. Mineral status in the body in mineral deficiency states, the body upregulates absorption of the mineral. In excess states, it downregulates absorption.
2. Substances present in food can enhance (e.g. ascorbic acid and Fe) or inhibit (e.g. phytates & Fe)
3. Other minerals present in food (or supplements) can compete for absorption: (e.g. iron supplements reduce Zn absorption; Zn antagonises Cu absorption).