Vitamin B1

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Vitamin B1 is a water-soluble vitamin, also known as Thiamine. It is found in whole wheat products, peas, beans, fish and meat, dairy products, fruits and eggs. The Recommended Daily Amount for adult males is 1.4mg and 1mg for adult females.

What is it needed for?

Thiamin plays a critical role in energy metabolism and, therefore, in the growth, development, and function of cells. It also plays a role in the health of the nervous system, in mental wellbeing and energy metabolism. Regular intake of thiamin is required as the body has a limited capacity to store this vitamin.


A deficiency of vitamin B1 may be associated withweight loss and anorexia, emotional problems, confusion, short-term memory loss, muscle weakness and pain and cardiovascular symptoms. Thiamin deficiency is also associated with beriberi, a condition which is characterized mainly by nerve pain and muscle wasting, resulting in impaired sensory, motor, and reflex functions.

High intakes of alcohol may impair the utilization and absorption of Vitamin B1 and therefore people with alcohol dependency may be at risk of vitamin B1 deficiency. Also, people with alcoholism tend to have inadequate intakes of essential nutrients, including thiamin. Thiamine deficiency has also been shown to be common in those with type 1 and type 2 diabetes.


Diabetes-Thiamine deficiency in those with type 1 and type 2 diabetes is common according to research (1). Oral supplementation with 150–300 mg/day thiamine has been shown to decrease glucose levels in patients with type 2 diabetes or impaired glucose tolerance in several small studies (2),(3). The effects of benfotiamine (a synthetic derivative of thiamine) supplements on diabetic neuropathy have also been assessed. Three randomized studies found that the severity of neuropathy symptoms was decreased as well as lowered urinary albumin excretion (a marker of early-stage diabetic nephropathy), compared to placebo with 120–900 mg/day benfotiamine with or without other B-vitamins (4),(5),(6).

Cardiovascular Health-There is thought to be an association between poor thiamine status and heart failure (7). It has been reported from one study that 33% of 100 patients with chronic heart failure had thiamine deficiency compared to 12% of 50 healthy volunteers (8).

Alzheimer’s Disease– Research suggests there may be a link between thiamine deficiency and the development of Alzheimer’s disease (9). Decreased brain activity of those with Alzheimer’s disease have been reported in autopsy studies (10).

Our take on how Vitamin B1 may help you based upon EU approved claims:

Digestive support- Thiamine contributes to normal energy-yielding metabolism. Vitamin B1 is required for the correct absorption and metabolism of fats, carbohydrates and proteins, making it valuable for people whose diets are high in in these nutrients. It helps support correct growth and development via the correct use of these nutrients.

Fatigue and tiredness- Vitamin B1 contributes to normal energy-yielding metabolism, a deficiency may be a factor in cases of tiredness and fatigue, and so a supplement may help prevent this. This may also be of value to those participating in sport to ensure the correct functioning of their energy metabolism to maximize performance.

Stress and related symptoms- Thiamine contributes to normal functioning of the nervous system. Vitamin B1 may help support cases of stress and low mood due to its role in the health of the nervous system. It is sometimes called the ‘morale vitamin’ because of its beneficial effects on the nervous system and mental attitude.

Alzheimer’s- Thiamine contributes to normal functioning of the nervous system. Vitamin B1 is thought to be involved in nerve transmission processes in the brain, and so preventing a deficiency may help slow deterioration.

Insect Bites- based upon anecdotal use, vitamin B1 may help reduce the likelihood of being bitten by insects.

Safety and side effects

The body excretes excess amounts of thiamin in the urineand therefore it is not associated with toxicity. For this reason no upper safe limit has been set for Thiamine.


  1. Page GL, Laight D, Cummings MH. Thiamine deficiency in diabetes mellitus and the impact of thiamine replacement on glucose metabolism and vascular disease. Int J Clin Pract 2011;65:684-90.
  2. Gonzalez-Ortiz M, Martinez-Abundis E, Robles-Cervantes JA, Ramirez-Ramirez V, Ramos-Zavala MG. Effect of thiamine administration on metabolic profile, cytokines and inflammatory markers in drug-naive patients with type 2 diabetes. Eur J Nutr 2011;50:145-9.
  3. Shahmiri F, Soares MJ, Zhao Y, Sherriff J. High-dose thiamine supplementation improves glucose tolerance in hyperglycemic individuals: a randomized, double-blind cross-over trial. Eur J Nutr 2013;52:1821-4.
  4. Stracke H, Gaus W, Achenbach U, Federlin K, Bretzel RG. Benfotiamine in diabetic polyneuropathy (BENDIP): results of a randomised, double blind, placebo-controlled clinical study. Exp Clin Endocrinol Diabetes 2008;116:600-
  5. Carpenter KJ. The discovery of thiamin. Ann Nutr Metab 2012;61:219-23.
  6. Rabbani N, Alam SS, Riaz S, Larkin JR, Akhtar MW, Shafi T, et al. High-dose thiamine therapy for patients with type 2 diabetes and microalbuminuria: a randomised, double-blind placebo-controlled pilot study. Diabetologia 2009;52:208-12.
  7. Wooley JA. Characteristics of thiamin and its relevance to the management of heart failure. Nutr Clin Pract 2008;23:487-93.
  8. Hanninen SA, Darling PB, Sole MJ, Barr A, Keith ME. The prevalence of thiamin deficiency in hospitalized patients with congestive heart failure. J Am Coll Cardiol  2006;47:354-61.
  9. Gibson GE, Hirsch JA, Cirio RT, Jordan BD, Fonzetti P, Elder J. Abnormal thiamine-dependent processes in Alzheimer’s Disease. Lessons from diabetes. Mol Cell Neurosci 2013;55:17-25.
  10. Gibson GE, Sheu KF, Blass JP, Baker A, Carlson KC, Harding B, et al. Reduced activities of thiamine-dependent enzymes in the brains and peripheral tissues of patients with Alzheimer’s disease. Arch Neurol 1988;45:836-40