Vitamin B1, also known as Thiamine, or Thiamin, as the “thio-vitamine” is a vitamin of the B complex. Thiamine is a water-soluble vitamin. So don’t boil your veges or it will be leached out in to the water! It is found in the tissue of most plants and animals.
Our body will only absorb so much thiamine and the rest will be excreted via urine. It is transported in plasma and red blood cells and is used to help turn carbohydrates in to energy for our body to use – this is especially important in the nervous system and brain. Thiamine also assists with the conduction of nerve signals and muscle contractions.
Where is thiamine found in food?
Thiamine is found mainly in cereal foods that have been fortified e.g. breads, rice, pasta. It is now mandatory for all baking flour within Australia to be fortified.
Good sources of thiamine include:
- Legumes and peas
- Nuts and seeds
- Eggs
- Liver
- Vegemite
- Kidney
- Lean pork
Consequences of Deficiency in Thiamine
Two conditions can develop from a deficiency in thiamine. One is known as Beri Beri and the other is Wernicke’s Encephalopathy. Both of these conditions can be quite serious if thiamine is not appropriately replenished.
Beri Beri
Beri Beri is not nearly common as it used to be – particularly in Malaysia, Japan and Indonesia. It is now occasionally seen in alcoholics due to depleted thiamine stores and an inadequate nutritional intake.
Complications of acute Beri Beri may include:
- Warm extremities
- High output cardiac failure
- Rapid pulse
- Oedema
- Cardiac enlargement
Individuals usually recover quickly once thiamine replacement is commenced. Chronic Beri Beri will impact the peripheral nerves opposed to the cardiovascular system.
It may present with the following symptoms:
- Loss of feeling in feet
- Difficulty lifting feet
- Loss of ankle reflexes
Wernicke’s encephalopathy
This occurs mostly in people who abuse alcohol and do not eat adequate amounts of thiamine.
Why does alcohol intake affect thiamine levels?
For alcohol to be metabolized thiamine is needed. Alcohol does not contain any thiamine. Therefore people who have a diet deficient in thiamine who regularly consume alcohol are likely to develop thiamine deficiency.
Wernicke’s encephalopathy is a neurological disorder caused by thiamine deficiency, typically from chronic alcoholism.
This condition presents with the following symptoms:
- Confusion
- Ataxia
- Decrease in consciousness
- Ophthalmoplegia
Treatment involves thiamine replacement therapy – recovery is usually seen within 2-3 days. Thiamine has a short half-life so multiple daily administrations may be necessary to replete levels and allow for optimal blood-brain diffusions. Oral preparations have been shown to vary in bioavailability, but in hospital practice, thiamine is usually administered parenterally to patients thought to be at high risk of Wernicke-Korsakoff syndrome (WKS).
All malnourished patients should be treated with large doses of parenteral thiamine, particularly if intravenous glucose administration is necessary, even in the absence of symptoms and signs of Wernicke’s Encephalopathy. Start thiamine prior to or concurrently with treatment of intravenous glucose solutions, and continue until the patient resumes a normal diet. The administration of dextrose or other carbohydrates in this setting has the potential for harm, because glucose oxidation is a thiamine-intensive process that may drive the last reserves of circulating vitamin B-1 toward the intracellular compartment, thereby aggravating neurologic damage.
If not treated promptly, permanent damage to the individuals memory may result e.g. difficulty retaining new memories. When the condition has progressed tot his point, it is referred to as Korsakoff’s psychosis. WKS was more common when Australia did not fortify our bread with thiamine. Since mandatory fortification has come in to place, Wernicke-Korsakoff syndrome is far less common.
Contact us for results focused nutritional advice
This article was written by our dietitian Belinda Elwin who is a Dietitians Association of Australia member and Accredited Practising Dietitian and Nutritionist. If you have questions about healthy eating, make an appointment. We‘ll provide you with a simple and effective routine targeted to your concerns. Contact us today.