Vitamin B1
Vitamin B1 (also known as thiamine or aneurine) is a water-soluble vitamin that cannot be stored in body fat, so it must be consumed daily. Vitamin B1 is easily affected by heat and its absorption is reduced by excessive consumption of alcohol, tea, coffee, raw fish, or shellfish. Over 50% of adults don’t get enough vitamin B1.
Roles
What does vitamin B1 do?
Vitamin B1 plays a critical role in:
- Transforming lipids (fat) and carbohydrates (sugars) into energy;
- Helping the cardiovascular, digestive, and nervous systems function properly;
- Growth.
Needs
Recommended Dietary Allowances for Vitamin B1:
| By Age Group | Recommended Dietary Allowance in mg/day | |
| Children | Ages 1 to 3 | 0.4 |
| Children and teens | Ages 4 to 18 | 0.6 to 1.1 |
| Adults | Age 18 and older | 1.5 |
| Pregnant women | | 1.6 |
| Nursing mothers | | 1.8 |
Source: Manuel Pratique de Nutrition, L’alimentation préventive et curative, p. 67-68, 2009.
Sources
Foods that provide adults with the most thiamine are enriched and whole grain cereal products such as breads, baked goods, and ready-to-eat cereals. Pork, cold cuts, peas, and spinach also contain vitamin B1.
Food Sources for Vitamin B1:
| Foods | Portion Size | Vitamin B1 (mg) |
| Peas, spinach | 25 to 100g | 0.1 |
| Nuts | 25 to 100g | 0.1 |
| Soy | 25 to 100g | 0.1 |
| Pork | 100g | 0.2-1 |
| Dried fruits | 100g | 0.2-0.8 |
| Liver, kidneys | 100g | 0.15-0.5 |
| Whole grain bread | 100g | 0.15-0.45 |
| Fish | 100g | 0.1-0.2 |
| Eggs | 100g | 0.1 |
| Potatoes, brown rice | 100g | 0.07 |
Source: Manuel Pratique de Nutrition; L’alimentation préventive et curative, 2009.
Deficiency
In developing countries, thiamine deficiency results in the onset of beriberi. This illness can affect infants breastfed by thiamine-deficient mothers, as well as alcoholics and those who consume too many processed carbohydrates, especially white rice which has had vitamin B1 removed during the polishing process. Fatigue and weight loss are the first signs of beriberi, which develops into two types, one attacking the nerves and muscles, the causing heart failure. In industrialized countries, thiamine deficiency is due primarily to excessive consumption of alcohol along with poor diet, and appears as Wernicke-Korsakoff syndrome, which results in psychological problems such as short-term memory loss, confabulation, and transient amnesia.
Signs of vitamin B1 deficiency:
- Anorexia;
- Swollen legs;
- Tiredness;
- Swelling in the hands and feet;
- Weight loss;
- Impaired mental condition (apathy, short-term memory loss, confusion, irritability);
- Muscular weakness;
- Cardiovascular problems (enlarged heart and tachycardia, an abnormally fast heart rate).
In serious cases, cardiovascular and renal complications may be life threatening.
Adverse effects
The body cannot ingest too much vitamin B1 because absorption drops off considerably after 5 mg, with any surplus simply eliminated in urine. According to reports in scientific publications, overconsumption of thiamine-rich foods or supplements has no harmful effect on health.
Additional information
Speak with your pharmacist if you plan to take vitamin B1 supplements. Your pharmacist can help you choose the solution that’s best for you based on your health and any drugs you take.
Other names
Vitamin B1, Thiamine, Aneurine