Nutrition Library

Vitamin B1 (Thiamine)

General Information
  • Vitamin B1 (thiamine) is a water-soluble B vitamin and is essential for the body.
  • Excess vitamin B1 is quickly excreted from the body, so regular intake is necessary.
  • It is very sensitive to heat.
  • In industrialized countries, most people have sufficient thiamine supply. A vitamin B1 deficiency (and corresponding consequences) may occur in the case of alcohol abuse or after bariatric surgery for morbid obesity.
  • Deficiency due to insufficient food variety is fairly common in in areas of food insecurity and restricted food choices.
Why Do We Need Vitamin B1?
  • As a coenzyme, vitamin B1 is involved in many metabolic reactions. In particular, it plays a central role in carbohydrate metabolism and in the nervous system.

    • Important for a functioning nervous system and formation of neurotransmitters (e.g., acetylcholine)
    • Energy metabolism
    • Carbohydrate and protein metabolism
    • Important for the immune system
    Possible Causes of Deficiency

    Insufficient intake:

    • Limited variation in the diet, with few foods rich in vitamin B1

    Increased intake requirements:

    • Pregnant and nursing mothers
    • Elderly individuals
    • Competitive athletes
    • Fever
    • Stress
    • High tea/coffee consumption (tannins)
    • Hyperthyroidism
    • Depression
    • Heart failure
    • Hemodialysis

    Reduced absorption: 

    • Bowel diseases such as Crohn’s disease or celiac disease
    • Bariatric surgery (surgery for obesity)

    Increased excretion:

    • Taking diuretics
    • Diabetes mellitus (loss of vitamin B1 due to kidney dysfunction)
    • Alcohol abuse

    Interaction with medications:

    • Increased vitamin B1 intake requirements: antiepileptics, cardiac glycosides (e.g., digitoxin), neuroleptics, tricyclic antidepressants
    • Impaired vitamin B1 intake: antacids, antibiotics, laxatives, oral contraceptives
    Symptoms of Deficiency
    • General: loss of appetite, depression, poor concentration, irritability, sleep disorders
    • Blood: anemia
    • Heart: heart failure, tachycardia, edema
    • Gastrointestinal: indigestion
    • Neurology: neuropathy (e.g., feet), muscle weakness or even paralysis, dizziness, hallucinations; together, these symptoms are known as Wernicke encephalopathy
    Recommended Intakes

    Recommended intake for adults and adolescents:

    • D-A-CH: Women 1.0 mg/day, Men 1.1–1.3 mg/day

    • USA Food and Nutrition Board (FNB): Women 1.1 mg/day, Men 1.2 mg/day

    Pregnant women:

    • D-A-CH: 1.3 mg/day

    • USA Food and Nutrition Board (FNB): 1.4 mg/day

    Breastfeeding women:

    • D-A-CH: 1.3 mg/day

    • USA Food and Nutrition Board (FNB): 1.4 mg/day

    Children, depending on age, see:

    The Best Plant Sources (per 100 g)

    Vitamin B1 is quite sensitive to heat. During cooking, up to 70% of the thiamin may be lost. Good vegetarian sources include legumes, potatoes, seeds, and nuts. B1 is found particularly in the outer layers of all types of grain.

    • Brewer’s yeast – 12 mg
    • Yeast flakes – 7.4 mg
    • Rice bran – 2.2 mg
    • Soybean meal – 2.2 mg
    • Sunflower seeds – 1.9 mg
    • Soy flour – 1.5 mg
    • Tahini – 1.3 mg
    • Mushrooms, dried – 1.0 mg
    • Soybeans – 1.0 mg
    • Peanuts – 0.9 mg
    • Pecans – 0.9 mg
    • Sesame – 0.8 mg
    • Pine nuts – 0.8 mg
    • Brazil nuts – 0.7 mg
    • Pistachios – 0.7 mg
    • Wheat bran – 0.7 mg
    • Oatmeal – 0.6 mg
    • Kidney beans – 0.6 mg
    • Beans – 0.6 mg
    • Walnuts – 0.5 mg
    • Flaxseed – 0.4 mg
    • Whole grain bread – 0.3 mg
    • Chickpeas – 0.3 mg
    • Peas, green – 0.3 mg
    • Asparagus – 0.2 mg
    • Spinach – 0.2 mg

     

    Sources
    • Biesalski, H.K., Bischoff, S.C., Pirlich, M., Weidmann, A., (2018). Ernährungsmedizin – Nach dem Curriculum Ernährungsmedizin der Bundesärztekammer (5.Auflage). Stuttgart: Georg Thieme Verlag

    • Gröber, U. (2011): Mikronährstoffe. Metabolic Tuning – Prävention – Therapie. 3. Aufl. Wissenschaftliche Verlagsgesellschaft mbH Stuttgart