Minerals

Question 1

Discuss the relevant amounts of ‘major minerals’ and ‘trace minerals’

Answer 1

Major minerals are considered as those minerals that are present in the body in levels greater than 5g. In order of most to least abundant, they are:

1. Calcium
2. Phosphorous
3. Potassium
4. Sulfur
5. Sodium
6. Chloride
7. Magnesium

Trace minerals include:

1. Iron
2. Zinc
3. Copper
4. Manganese
5. Iodene
6. Selenium

Question 2

Discuss the nutritional value of Calcium

Answer 2

Question 3

What is malignant hyperthermia?

What roles does calcium play in this condition?

Answer 3

Malignant hyperthermia is a life-threatening condition that is triggered by exposure to drugs used for general anaesthesia.

Malignant hyperthermia occurs when muscle
releases excess Ca2+ and muscle becomes an
uncontrolled ATPase.

Uncontrolled oxidative metabolism overwhelms the body’s capacity to supply oxygen, remove carbon dioxide and regulate body temperature, eventually leading to circulatory collapse and death if not treated quickly (ice and dantrolene).

is often inherited as an autosomal dominant
disorder associated with multiple loci, particularly in the **ryanodine receptor gene (RYR1). **

The muscle relaxant dantrolene stops Ca2+ from coupling to the contraction cycle and protects against malignant hyperthermia

Question 4

Discuss the nutritional value of phosphorous

Answer 4

In the environment, phosphorous is always present in its maximally oxidised form inorganic phosphate (P₂0₅)

In the human body, phosophate is mostly present as hydroxyapatite in bones

Phosphate it is essential to human life; it is a component of DNA, RNA, ATP and all of the phospholipids that form cell membranes

Low phosphorous levels inhibit growth in biological systems. Excess phosphate in water ways leads to eutrophication

Question 5

Discuss the nutritional value of potassium

Answer 5

Banana’s are good source of potassium. A medium sized one will provide 10% of daily potassium needs and 7% of daily magnesium leves - but only 4% of kJ

Ripe tomatos are also a a great source of potassium + they have the anitoxidant lycopene. Both K+ and lycopene are thought to explain clinical trials where tomatos reduced heart disease

Question 6

Discuss the nutritional value of sodium

Answer 6

Question 7

Discuss the nutritional value of chloride

Answer 7

Question 8

Discuss the nutritional value of magnesium

Answer 8

Note: Epsom Salt (MgSO₄)

• Commonly used as a saline laxative
• Topical application in treating aches and pains
• first-line antiarrhythmic agent for torsades de pointes in cardiac arrest
• As a bronchodilator after beta-agonist and anticholinergic agents have been tried, e.g. in severe exacerbations of asthma
• Eclampsia in pregnant women.
• Delay premature labour, to delay preterm birth.
• Prevent cerebral palsy in preterm babies
• Topical use can soothe and relieve herpes outbreaks
  *

Question 9

Discuss the nutritional value of iron

Answer 9

Iron deficiency is the most medically significant mineral deficiency in the the world; affecting 1 billion people.

Dietary iron is mostly Fe³⁺ but only Fe²⁺ is absorbed

There is ~2-4g of Iron in the body

Daily turnover of iron ~ 2-4mg in and out

Food contains ~10mg a day -> but most of this is in the unabsorbable Fe³⁺

Vitamin C assists in the absorption of Fe²⁺

Question 10

What is hereditary haemochromatosis?

Answer 10

** Hereditary haemochromatosis **is a serious and potentially fatal excess of iron accumulation in the body as the result of defects to iron carrier proteins (ferritin and/or transferrin)

Diseases associated with hemochromatosis are arthritis, cirrhosis of the liver, diabetes, heart failure, and liver cancer.

Question 11

Discuss the nutritional value of Zinc

Answer 11

Question 12

Discuss the nutritional value of copper

Answer 12

Question 13

Describe the implications of copper deficiencies and excesses

Answer 13

The daily copper requirement is about 1-2 mg. Copper is absorbed by the intestinal cells and
stored with metallothionein in a non-toxic form.

The copper is later delivered into the circulation by a copper transporter protein, copper-transporting ATPase 1 (ATP7A)

Menke’s Disease (deficiency)

X linked mutation of the ATP7A gene results in the storage (not release) of copper in enterocytes (gut mucosa), thereby causing a severe copper deficiency.

Wilson’s Disease (excess)

Is a genetic disease leading to high serum
copper and copper toxicity due to overactivity of ATP7A. Give characteristic ring around cornea of copper (Kayser-Fleischer Ring)

Question 14

Discuss the nutritional value of manganese

Answer 14

Question 15

Discuss the nutritional value of iodine

Answer 15

Question 16

Describe the nutritional value of selenium

Answer 16

Question 17

Discuss the nutritional value of chromium

Answer 17

Question 18

Discuss the nutritional value of molybdenum

Answer 18

Question 19

Discuss the nutritional value of Fluoride

Answer 19