Vitamin B1 (Thiamine)


What is it?

Vitamin B1 or Thiamine is a water-soluble vitamin.

What does it do?

  • Tiredness, irritability, poor concentration, poor memory
  • Muscle weakness or tenderness
  • Stomach pains, digestive disorders, constipation
  • Severe deficiency results in the disease beri-beri.

Deficiency Symptoms

  • Poor sense of taste or smell
  • White marks on fingernails
  • Infertility
  • Frequent colds and infections
  • Acne or greasy skin
  • Pale skin
  • Hair loss

Recommended Daily Amount (RDA)

Children 0.4 – 1.1mg
Adults 0.8 – 1mg

B vitamins tend to function best when in combination with the other B vitamins, rather than in isolation, and therefore it is usually recommended that it B1 is supplemented as part of a B complex.

Food Sources

Soy beans, brown rice, sunflower seeds, whole wheat, nuts, oats, pulses, watercress, asparagus, courgette, peas.

Safety Considerations

There are no associations with toxicity.


Please note that products, product info and all other info on this site (including multimedia content & links) are not intended for treating or diagnosing specific medical conditions. If you are unwell, pregnant, or on medication, please consult a doctor before starting supplements. Do not exceed recommended dosages and please keep all supplements out of the reach and sight of children.