Comprehensive Guide to Vitamin B1-Thiamine

Vitamin B1-ThiamineDr. James Meschino DC, MS, ND
Download in PDF format Download in Epub format Download in Kindle format
The B-Vitamins play an essential role in the metabolic processes of all living cells by serving as cofactors in the various enzyme systems involved in the oxidation of food and production of energy. Some B-Vitamins are required for DNA synthesis, the formation of myelin, neurotransmitters, creatine, red blood cells and participate in other vital functions, such as maintaining safe blood levels of homocysteine.

Vitamin B1, or Thiamine, is known as the antineuritic vitamin because it is needed for normal functioning of the nervous system.
Absorption and Metabolism

Thiamine is absorbed in the proximal and lower duodenum. It is phosphorylated in the mucosal cell to Thiamine phosphate and then carried to the liver by the portal circulation. It is not stored in any great quantity in the body and must, therefore, be supplied daily.


Energy metabolism

Thiamine combines with phosphorus to form the coenzyme Thiamine pyrophosphate (TPP), which is necessary to convert pyruvate to acetyl coenzyme A, the central compound of the Kreb's cycle. The Krebs cycle yields ATP energy to power all biological reactions within the body.

Synthesis of Nucleotides and Fatty Acids

TPP is required in the pentose phosphate shunt, which is necessary to synthesize nucleotides, required to make DNA and RNA, and for fatty acids.

Nerve conduction

TPP affects the nerve cell membrane in a manner that facilitates normal nerve transmission. This is a non-coenzyme function of Thiamine.

Recommended Dietary Allowance (Vitamin B1/Thiamine)
RDA Thiamine0.7-1.0 mg. per day
Adults (1.0-1.5 mg)1 mg per day
Pregnancy1.4 mg per day
Lactation1.6 mg per day
Infants under 6 months0.3 mg per day
6-12 months0.4 mg per day
Ages 1 to 10 years(progressive increase)


Classical Vitamin B1 Deficiency
  1. Beriberi

    Beriberi is a condition that affects the nervous system and/or the heart muscle. Lack of ATP synthesis in Vitamin B1 deficiency (Beriberi) results in loss of function or paralysis of the lower extremities (polyneuritis) and/or heart failure. In modern society, it is most common in alcoholics.
  2. Wernicke-Korsakoff Syndrome

    This is a syndrome often found in alcoholics, includes encephalopathy, with loss of immediate memory, disorientation, nystagmus and/or ataxia, as well as signs and symptoms of polyneuritis and related B1 deficiency signs and symptoms.1

Vitamin B1 Supplementation
  1. Epileptics taking Dilantin

    Typically experience improved mental function has been noted in these subjects with 50 mg Thiamine supplementation in a six-month trial.2

  2. Alzheimer's Disease

    Many Alzheimer's Disease patients have been shown to have poor B1 nutritional status.3 Thiamine demonstrates some pharmacological effects on the brain in that it mimics acetylcholine, the memory neurotransmitters.4 Thiamine has been shown to improve mental function in patients with Alzheimer's Disease and age-related impaired mental function (senility) at a dose of 3 to 8 grams per day. The long-term consequences of a dose this high is unknown at this time, but no significant side effects have been reported in these preliminary trials.5,6

  3. Congestive Heart Failure

    Older individuals often display poor nutritional status for Vitamin B1. Many diuretic drugs used for high blood pressure and congestive heart failure cause a depletion of Thiamine, which is needed for energy production in heart muscle.3,7 In a trial supplementing patients with congestive heart failure with 80-240 mg of Thiamine, there was an increase in left ventricular ejection fraction of 13 to 22 percent, on average. This outcome is associated with improved survival.8

  1. Mouth Ulcers (Cankers or Apthous Stomatitis)

    Supplementing with 300 mg B1, 20 mg B2 and 150 mg B6 has been reported to provide relief in people suffering from regular outbreaks of canker sores. Thiamine deficiency is strongly linked to apthous ulcer vulnerability.9,10
  2. Depression

    Deprivation of Thiamine (0.33 mg per day) results in signs of depression, fatigue, headaches, including voluntary restriction of social engagements. Symptoms were alleviated when subjects were given 1.4 mg of Thiamine for only one day in one study.11

Vitamin B1 Toxicity

Thiamine appears to be very non-toxic even at high levels of intake ≥ 100 mg per day.11,12

Drug-Nutrient Interactions
  1. Alcohol

    Alcohol interrupts the conversion of Thiamine to its active form, which can result in Vitamin B1 deficiency with excessive intake.13

  2. The following drugs are also reported to cause Thiamine depletion:

    Antibiotics: decrease B1 synthesis by bacterial flora14,15

    Loop Diuretics: cause increased urinary loss of Thiamine16

    Oral Contraceptives17

    Phenytoin (anti-seizure drug)8

Standard Textbooks of Nutritional Science:

   - Shils M, Shike M, Olson J, Ross C. Modern Nutrition in Health and Disease. 9th ed. Baltimore, MD: Lippincott Williams & Wilkins; 1993.

   - Escott-Stump S, Mahan LK, editors. Food, Nutrition and Diet Therapy. 10th ed. Philadelphia, PA: W.B. Saunders Company; 2000.

   - Bowman B, Russell RM, editors. Present Knowledge in Nutrition, 8th ed. Washington, DC:.ILSI Press; 2001.

   - Kreutler PA, Czajka-Narins DM, editors. Nutrition in Perspective. 2nd ed. Upper Saddle River, NJ: Prentice Hall Inc.; 1987.

Botez MI, Botez T, Ross-Chouinard A, Lalonde R. Thiamine and folate treatment of chronic epileptic patients: a controlled study with the Wechsler IQ scale. Epilepsy Res 1993;16(2):157-63.

Chen MF, et al. Plasma and erythrocyte Thiamine concentration in geriatric outpatients. J Am Coll Nutr 1996;15;2331-6.

Meador KJ, Nichols ME, Franke P, Durkin MU, Oberzan RL, Moore EE, et al. Evidence for a central cholinergic effect on high-dose Thiamine. Ann Neurol 1993;34:724-6.

Meador K, Loring D, Nichols M, Zanrini E, Rivner M, Posas H, et al. Preliminary finding of high-dose Thiamine in dementia of Alzheimer's type. J Geriatr Psychiatry Neurol 1993;6:222-9.

Benton D, Fordy J, Haller J. The impact of long-term vitamin supplementation on cognitive function. Psychopharmacol 1995;117:298-305.

Murray M, Pizzorno J. Encyclopedia of Natural Medicine. 2nd edition. Rocklin, CA: Prima Publishing; 1998.

Leslie D, Gheorghiade M. Is there a role for Thiamine supplementation in the management of heart failure? Am Heart J 1994;131:125-30, 1248-50.

Nolan A, McIntosh WB, Allam BF, Lamey PJ. Recurrent aphthous ulceration: vitamin B1, B2 and B6 status and response to replacement therapy. J Oral Pathol Med 1991;20:389-91.

Haisraeli-Shalish M, Livneh A, Katz J, et al. Recurrent apthous stomatitis and Thiamine deficiency. Oral Surg, Oral Med, Oral Path, Oral Radio/Endod 1996;82:634-6.

Guthrie HA. Introductory Nutrition. 7th ed. St. Louis, MO: Mosby College Publishing; 1989.

Kreutler P, Czajka-Narins DM. Nutrition in Perspective. 2nd ed. Englewood Cliffs, NJ: Prentice Hall; 1987.

Hoyumpa AM Jr. Mechanisms of Thiamin deficiency in chronic alcoholism. Am J Clin Nutr 1980;33(12):2750-61.

Cummings JH, Macfarlane G. Role of intestinal bacteria in nutrient metabolism. J Parenter Enteral Nutr 1997;21(6):357-65.

Deguchi Y,Morishita T, Mutai M. Comparative studies on synthesis of water-soluble vitamins among species of bifidobacteria. Agric Biol Chem 1985;49(1):13-9.

Brady JA, Rock CL, Horneffer MR. Thiamin status, diuretic medications, and the management of congestive heart failure. J Am Diet Assoc 1995;95(5):541-4.

Brigg MG, Briggs M. Thiamine status and oral contraceptives. Contraception 1975:11(2):151-4.

Botez MI, Joyal C, Maag U, Bachevalier J. Cerebrospinal fluid and blood Thiamine concentrations in phenytoin-treated epileptics. Can J Neurol Sci. 1982;9(1):37-9.

Landrum JT, Bone RA, Kilburn MD. The macular pigment: a possible role in protection from age-related macular degeneration. Adv Pharmacol 1997;38:537-56.

Seddon JM, Ajani UA, Sperdato RD. Dietary carotenoids, Vitamin A, C, and E, and advanced age-related macular degeneration. JAMA 1994;272:1413-20.

Hankinson SE, Stampfer MJ, Seddon JM, Colditz GA, Rosner B, Speizer FE, et al. Nutrient intake and cataract extraction in women: a prospective study. Br Med J 1992;305:335-9.

Murray M, Pizzorno J. Encyclopedia of Natural Medicine. 2nd edition. Rocklin, CA: Prima Publishing; 1998.

Berendschot TT, Goldbohm RA, Klopping WA, van de Kraats J, van Norel J, van Norren D. Influence of Lutein supplementation on macular pigment, assessed with two objective techniques. Invest Ophthalmol Vis Sci 2000;41(11):3322-6.

Landrum JT, Bone RA, Joa H, Kilburn MD, Moore LL, Sprague KE. A one year study of the macular pigment: the effect of 140 days Lutein supplement. Exp Eye Res 1997;65(1):59-62.

Dagnelie G, Zorge IS, McDonald TM. Lutein improves visual function in some patients with retinal degeneration: a pilot study via the Internet. Optometry 2000;71(30):147-64.

Khachik F, Bernstein PS, Garland DL. Identifaction of lutein and zeazanthin oxidation products in human and monkey retinas. Invest Ophthalmol Vis Sci 1997;38(9):1802-11.

Sommerburg O, Keunen JE, Bird AC, Van Kuijk FJ. Fruits and vegetables that are a source of lutein and zeazanthin: the macular pigment in human eyes. Br J Ophthalmol 1998;82(8):907-10.

Sommerburg OG, Siems WG, Hurst JS, Lewis JW, Kliger DS, van Kuijk FJ. Lutein and zeazanthin are associated with photoreceptors in the human retina. Curr Eye Res 1999;19(6):491-5.

Rapp LM, Maple SS, Choi JH. Lutein and zeazanthin concentrations in rod outer segment membranes from perifoveal and peripheral human retina. Invest Ophthalmol Vis Sci 2000;41(5):1200-9.

Johnson EJ, Hammond BR, Yeum KJ, Qin J, Wang XD, Castaneda C, et al. Relation among serum and tissue concentrations of lutein and zeazanthin and macular pigment density. Am J Clin Nutr 2000;71(6):1555-62.

Bone RA, Landrum JT, Dixon Z, Chen Y, Llerena CM. Lutein and zeazanthin in the eyes, serum and diet of human subjects. Exp Eye Res 2000;71(3):239-45.

Hathcock JN. Evaluation of Vitamin A toxicity. Am J Clin Nutr 1990;52:183-202.

Heck AM, Yanovski JA, Calis KA. Orlistat, a new lipase inhibitor for the management of obesity. Pharmacotherapy 2000;20(3):270-9.

Xenical (orlistat), product prescribing information. Nutley, NJ: Roche laboratories, Inc.; 2000.

Finer N, James WP Kopelman PG, Lean ME, Williams G. One year treatment of obesity: a randomized, double-blind, placebo-controlled, multicentre study of orlistat, a gastrointestinal lipase inhibitor. Int J Obes Relat Metab Disord 2000;24(3):306-13.

Diarrhea and Constipation. In: Berdow R, Fletcher AJ, Beers MH, et al, editors. The Merck manual of diagnosis and therapy. 16th ed. Rahway, NJ: Merck research laboratories; 1992. p. 810.

Schwarz KB, Goldstein PD, Witztum JL, Schonfeld G. Fat-soluble vitamin concentrations in hypercholesterolemic children treated with colestipol. Pediatrics 1980;65(2):243-50.

Knodel LC, Talbert RL. Adverse effects of hypolipidaemic drugs. Med Toxicol 1987;2(1)10-32.

Koonsvitsky BP, Berry DA, Jones MB, Lin PY, Cooper DA, Jones DY, et al. Olestra affects serum concentrations of alpha-tocopherol and carotenoids but not Vitamin D or Vitamin K status in free-living subjects. J Nutr 1997;127(8 Suppl):1636S-1645S.

Thomson AB, Hunt RH, Zorich NL. Review Article: Olestra and its gastrointestinal safety. Aliment pharmacol Ther 1998;12(12):1185-200.

Deuchi K, Kanauchi O, Shizukuishi M, Kobayashi E. Continuous and massive intake of chitosan affects mineral and fat-soluble vitamin status in rats fed on a high-fat diet. Biosci Biotechnol Biochem 1995;59(7):1211-6.

Webb D. Can lutein pills save your precious sight? Supplement News – Prevention 2000;52(11):57, 2, 2c.

Cantrell S, Ausich RL. Exploring the role of antioxidants in preventing ARMD. Optometry Today 1999.

Pratt S. What we know about ARMD and nutrition. Rev of Ophthalmology. 1998.