Thiamine -Water soluble Vitamin
Key Highlights
- Main function: energy metabolism.
- RDA: men, 1.2 mg; women, 1.1 mg.
- No toxicity reported, no upper intake level set.
- Deficiency disease: beriberi.
- Healthy food sources: whole grains, and found in most raw or lightly cooked foods.
- Degradation: easily destroyed by heat.
- Coenzyme forms: Thiamin Pyro Phosphate (TPP), Thiamine Triphosphate (TTP)
Main Functions
- Thiamine (vitamin B1) Water-soluble member of the B-complex vitamins, whose deficiency is the cause of beriberi.
- Thiamine is an important coenzyme required for the intermediary metabolism of carbohydrates and some amino acids.
- It is especially vital for a normally functioning central nervous system.
- Thiamine also is vitally involved in the conversion of fatty acids into steroids and is essential for normal growth and skin integrity.
- It also exhibit anti-oxidant properties .
- Vitamin B1 deficiency causes beriberi.
- B1 plays a key role in the metabolism of energy in all cells. Thiamine is part of the coenzyme Thiamin Pyro Phosphate (TPP), which helps convert pyruvate to acetyl-coenzyme A (also known as acetyl-CoA). This is a necessary step in the production of cellular energy from carbohydrates .
Deficiency of B1
Beriberi :The disease is most common in infants between the ages of two and three months. Afflicted babies exhibit a distinctive cry that varies from a loud piercing cry to hoarseness or aphonia (a total loss of voice).
They become cyanotic, short of breath, vomit, have tachycardia (a rapid heart rate),develop an enlarged heart and may convulse. Death may result in a matter of hours, unless thiamine is administered.
Thiamine and vitamin B12 are the only vitamins whose deficiencies have proven causes of neurologic disease. It takes only three weeks of total dietary lack of thiamine to see the first signs of deficiency.
Persons with a subclinical or minimal thiamine deficiency may exhibit behavioral changes such as irritability, frequent headaches and fatigue
Malnourished patients, especially those with severe alcoholism, are likely to develop the Wernicke-Korsakoff syndrome, or “cerebral beriberi.” Wernicke’s syndrome is characterized by ocular abnormalities such as
- dysfunction of the cerebellar or vestibular regions of the brain causing ataxia,
- paralysis of the muscles controlling the movements of the eyes,
- staggering gait; and generalized confusion,
- patient appearing listless and spatially disoriented.
- Lethargy is common but stupor and coma are rare.
Recommended Dietary Allowances
RECOMMENDED DIETARY ALLOWANCES FOR THIAMINE (VITAMIN B1)
| Category | Age | Dosage in mg |
| Infant | 0-6 Months | 0.3 |
| 6-12 Months | 0.4 | |
| Toddlers | 1 to 3 yeas | 0.7 |
| Children | 4 to 6 Years | 0.9 |
| 7 to 10 years | 1.0 | |
| Males | 11 to 14 years | 1.3 |
| 15 to 50 Years | 1.5 | |
| Over 50 years | 1.2 | |
| Females | 11 to 50 Years | 1.1 |
| Over 50 Years | 1.0 |
Dietary sources
Thiamine is widely found in plant and animal food sources but there are significant amounts in only a few. Meat, especially liver and pork; dried beans; peas; soybeans; peanuts; whole grains; egg yolk; poultry; and fish are the richest dietary sources of thiamine.