Vitamin B1 - Thiamine

Question 1

Vitamin B1: Thiamine

Answer 1

• Vitamin B1 (thiamine) functions in the body as the active form ‘thiamine pyrophosphate’ (TPP); conversion to this enzyme is dependent on magnesium , and impaired by alcohol.

Question 2

Vitamin B1: Storage and preparation

Answer 2

• Bodily stores of B1 would last for approximately 1 month.
• B1 content is very easily reduced by processing including milling,
chopping, canning, adding sulphites (e.g. dried fruit), baking soda. Boiling or freezing reduces B1 content by 50%. Toasting bread reduces B1 by 30%. Fresh, raw sources are best

Question 3

Vitamin B1 - Food Sources

Answer 3

• Yeast extract, peas, oranges, nuts (e.g. macadamia), pulses, sunflower seeds, wholegrains, meat / fish.

Question 4

Vitamin B1 - Roles

Answer 4

Energy (ATP) production

Nervous System Functioning

Question 5

Vitamin B1: Energy (ATP) production - Functions

Answer 5

• Crucial for carbohydrate, as well as fat and protein metabolism .
• Needed for the formation of Acetyl CoA (key for ATP production). -> Krebs Cycle

Question 6

Vitamin B1: Energy (ATP) production - Therapeutic Uses

Answer 6

• Fatigue
• Supporting energy production in increased need (e.g. pregnancy, heart failure)
• Fertility

Question 7

Vitamin B1 - Nervous System Functioning - Functions

Answer 7

• Acetyl CoA is an important precursor of acetylcholine ->

* The amino acids that are metabolised by thiamine can be used to create neurotransmitters e.g. GABA.

Question 8

Vitamin B1 - Nervous System Functioning - Therapeutic Uses

Answer 8

• Cognitive decline and memory loss
• Alzheimer’s
• Low mood
• Parkinson’s
• Nerve repair

Question 9

Vitamin B1 - Nervous System Functioning - Therapeutic Uses

Answer 9

• Cognitive decline and memory loss
• Alzheimer’s
• Low mood
• Parkinson’s
• Nerve repair

Question 10

Vitamin B1 - Dietary Requirements

Answer 10

Dietary requirements:
• The more carbohydrate you eat, the more B1 you need (i.e. to create ATP from it). An average of 0.4-0.5 mg/1000kcal is recommended.

Question 11

Vitamin B1 - Absoption

Answer 11

Absorption is impaired by:

• Alcohol, tea (tannins), coffee, the OCP, stress and antacids.

Question 12

Vitamin B1 - Absorption

Answer 12

Absorption is impaired by:

• Alcohol, tea (tannins), coffee, the OCP, stress and antacids.

Question 13

Vitamin B1 Deficiency

Answer 13

Deficiency (Beriberi):
• Beriberi is the primary deficiency disease. Most forms are rare in the West. A white rice diet is thiamine depleted (these are at risk).
• Alcoholics are particularly prone to deficiency ––‘cerebral beriberi’ (Wernicke Korsakoff syndrome) is most common Western cause.

Question 14

Vitamin B1 Deficiency - Signs and Symptoms

Answer 14

• Depression, irritability, fatigue, memory loss, muscle weakness and cramps, GIT disturbance.
• Be aware that elderly people are frequently more depleted of thiamine and can benefit from it.

Question 15

Vitamin B1 - Toxcitiy

Answer 15

Only seen in supplementation (i.e. 5g daily), but is rare.