What it does
The NIH consumer sheet says thiamin helps turn the food you eat into the energy you need. It also says thiamin is important for the growth, development, and function of cells.
What research can and cannot say
The sheet says most people in the United States get enough thiamin from food. It says scientists are still studying thiamin in diabetes, heart failure, and memory. A labeled amount is not a result for any of those.
A thiamin label does not show that a bottle changes energy, blood sugar, or memory. Benfotiamine on a label is a synthetic form, not a different result.
Forms and label reading
Common supplement forms are thiamin mononitrate and thiamin hydrochloride. Some supplements use benfotiamine, a synthetic form. Read the form and the mg per serving on the Supplement Facts panel.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Amount and upper limit
Recommended amount. The NIH sheet lists 1.2 mg a day for men and 1.1 mg a day for women. It lists 1.4 mg for pregnant teens and women and for breastfeeding teens and women. Cited sheet
Upper limit. The consumer sheet does not list an upper limit. It says thiamin has not been shown to cause any harm. Cited sheet
Safety
The sheet says too little thiamin can cause loss of weight and appetite, confusion, memory loss, muscle weakness, and heart problems. Severe deficiency is called beriberi and is uncommon in the United States. Furosemide and fluorouracil are examples of medicines that can lower thiamin levels.
Food sources
The sheet names whole grains and fortified bread, cereal, pasta, and rice; meat, especially pork, and fish; and legumes such as black beans and soybeans, plus seeds and nuts.
