Vitamin B1 deficiency (Beriberi)
Linked to Vitamin B1 (Thiamin)
Thiamin deficiency affects the nerves and heart and, with alcohol, the brain.
Where it shows on the body
Rotate the figure and click a red marker to see the affected area. Internal organs open a 3D organ model.
Causes
- Diets high in polished rice
- Heavy alcohol use
- Malnutrition
Symptoms
- Tingling and numbness
- Muscle weakness
- Swelling (wet beriberi)
- Rapid heart rate
- Confusion
What happens if untreated
- Heart failure
- Wernicke-Korsakoff brain damage with alcohol
Who is most at risk
- People with alcohol dependence
- Those on very limited diets
Prevention & sources
- Wholegrains, legumes, pork
- Thiamin supplements in at-risk people
Correcting it: foods, amounts & timing
Foods that help & safe amounts
- Wholegrains, pork, legumes and fortified cereals
- Thiamin supplements for those at risk (e.g. with alcohol dependence), as prescribed
Nerve and heart symptoms can improve within days to weeks of treatment.
Sources & references
Symptoms overlap — testing matters
Most deficiency symptoms (fatigue, poor concentration, skin and hair changes) are shared across several nutrients and many unrelated conditions. A symptom on this page is a reason to investigate, not a diagnosis.
A GP can confirm or rule out a deficiency with a blood test and check for underlying causes such as absorption problems. Do not start high-dose supplements on suspicion alone — some nutrients are harmful in excess, and supplementing before testing can mask the underlying result.