Vitamin
Vitamin B1
Vitamin B1 (thiamine) helps the body release energy from food and keeps the nervous system healthy. It is found in many foods, so deficiency is uncommon in the UK.
What it is
Thiamine is a water-soluble B vitamin that the body cannot store in large amounts, so a regular supply from food is needed.
What it does
It helps the body break down and release energy from food, particularly carbohydrates, and keeps the nervous system working properly.
Good sources
Wholegrains and fortified cereals, peas, pulses, nuts, pork, and some fortified breads and breakfast cereals.
Deficiency and who is at risk
Deficiency is uncommon in the UK but can occur with poor diet or heavy alcohol use, causing tiredness, nerve problems and, if severe, a serious condition affecting the brain and heart. People who drink heavily are particularly at risk.
Balance
Can you have too much?
Thiamine from food is not harmful, and excess is passed out in the urine. Very high supplement doses are not generally needed.
Education and reference only. This is general nutrition information, not personal advice, and does not give doses. Ask a pharmacist, GP or registered dietitian before starting supplements, especially with a health condition or in pregnancy.
Answers
Vitamin B1: frequently asked questions
Who is at risk of thiamine deficiency?
People who drink alcohol heavily, have a very poor diet, or have certain digestive or absorption problems are most at risk, and may need supplements under medical advice.
What does thiamine do?
It helps your body turn food, especially carbohydrates, into energy and keeps your nerves working properly, which is why deficiency can cause tiredness and nerve symptoms.
Related
More on vitamins and nutrition
Sources
Where this is drawn from
- NHS — Vitamins and minerals
- British Dietetic Association (BDA)
- UK Scientific Advisory Committee on Nutrition (SACN)
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