Matthew Messer

Matthew Messer


Vitamin B1, also called thiamin is an essential, water-soluble vitamin. As the body can only store a very limited amount of it, daily intake is advised. It has an indispensable role in metabolism: vitamin B1 deficiency results in the body’s inability to produce sufficient energy from food, which leads to fatigue at first, then serious issues can follow in the nervous system and cardiovascular system. (1

How common is vitamin B1 deficiency? 

Severe vitamin B1 deficiency is relatively rare, as the vitamin can be found in various food items. Risk groups include alcohol addicts or malnourished individuals. Modern diets include a lot of processed food, such as white flour, sugar and oils which hardly contain any thiamin. (3

High blood sugar levels and alcohol consumption quickens the body’s process of disposing of thiamin. As a consequence, a higher intake of vitamin B1 is necessary to prevent deficiency. Obese people whose diet typically does not include vitamin B1-rich foods also often have vitamin B1 deficiency. (4

Vitamin B1 sources  

Most organic foods contain some vitamin B1, but in a fairly low dosage. It can be found in meat, fish, vegetables, whole wheat and pulses. During digestion the body’s enzymes break down the vitamin B1 found in food to free thiamin, which is then turned into active forms inside the cells.  

It’s important to note that since food contains meagre amounts of vitamin B1, and in a form that can only be utilised through adequate digestion, vitamin B1 supplementation is strongly advised if a vitamin B1 deficiency exists. 

The forms of thiamin most commonly found in supplements, thiamine-hydrochloride and thiamin-mononitrate, immediately dissolve in the stomach and turn into free thiamin; and thanks to their high concentration they can also be absorbed through passive diffusion. This is beneficial for those whose proteolytic enzymes do not function properly due to digestive issues or other health problems. 

When are supplements paramount? 

Alcohol is one of the main causes of vitamin B1 deficiency as it blocks its absorption from food. However, as supplements contain a significantly larger dose than organic food and can be absorbed through passive transport as mentioned above, alcohol cannot block the process. (5

Alcohol addiction, diabetes, obesity, and other digestive issues either increase the need for vitamin B1 or decrease the effectiveness of its absorption, so these conditions warrant vitamin B1 supplementation. 

Are there benefits to supplementing a higher dosage? 

There is no known dangerous dosage of vitamin B1. The body can easily get rid of the excess in the event of an overdose. As vitamin B1 plays a key role in metabolism, everybody can benefit from supplementing it, especially the at-risk groups mentioned above. In addition, two studies found that vitamin B1 supplementation significantly lessens severe symptoms of PMS. (6,7


Vitamin B1 is one of the most important components of digestion; deficiency leads to decreased energy levels, which, in time, can lead to serious illness. Most modern processed foods don’t contain vitamin B1, even though it would be necessary for turning the food into energy. 

The majority of organic food contains vitamin B1, but in a small concentration. Certain digestive enzymes are needed for the absorption of vitamin B1 from food, but these can work less effectively due to digestive issues, excessive alcohol consumption or other illnesses. 

Supplementing vitamin B1 is a cheap and practical solution and it’s highly recommended if the above mentioned issues occur, as in the optimal concentration the body can easily utilise it even without digestive enzymes.

Fun fact 

Beriberi, a disease caused by vitamin B1 deficiency has been around for centuries, but its exact causes were only discovered in 1897. The breakthrough came when scientists observed that chicken who were only fed white rice would eventually became lame, while chicken who were fed brown rice had no such health concerns. This made the scientists realize that the cause of the disease was something found in or missing from the food; thiamin was synthesised not much later. (2

[The cover photo of the note shows macadamia nuts. 100 grams contain 1.2 mg of vitamin B1, which provides the entire daily requirement]

  1. Wiley KD, Gupta M. Vitamin B1 Thiamine Deficiency. 2021 Jun 21. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan–. PMID: 30725889. 

  2. Carpenter KJ. The discovery of thiamin. Ann Nutr Metab. 2012;61(3):219-23. doi: 10.1159/000343109. Epub 2012 Nov 26. PMID: 23183292. 


  4. Kerns JC, Arundel C, Chawla LS. Thiamin deficiency in people with obesity. Adv Nutr. 2015 Mar 13;6(2):147-53. doi: 10.3945/an.114.007526. PMID: 25770253; PMCID: PMC4352173. 

  5. Dhir S, Tarasenko M, Napoli E and Giulivi C (2019) Neurological, Psychiatric, and Biochemical Aspects of Thiamine Deficiency in Children and Adults. Front. Psychiatry 10:207. doi: 10.3389/fpsyt.2019.00207 

  6. Abdollahifard S, Rahmanian Koshkaki A, Moazamiyanfar R. The effects of vitamin B1 on ameliorating the premenstrual syndrome symptoms. Glob J Health Sci. 2014 Jul 29;6(6):144-53. doi: 10.5539/gjhs.v6n6p144. PMID: 25363099; PMCID: PMC4825494. 

  7. Samieipour, S., Kiani, F., pour, Y.S., Heydarabadi, A.B., Tavassoli, E., & zade, R.R. (2016). Comparing the Effects of Vitamin B1 and Calcium on Premenstrual Syndrome (PMS) among Female Students, Ilam- Iran. International Journal of Pediatrics, 4, 3519-3528. 

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