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Thiamin (Vitamin B1)

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What is Thiamin?

Thiamin, also called vitamin B1, is an essential nutrient that is associated with the action of many of the body’s enzymes and in the conversion of food into energy.1

Benefits of Thiamin

Thiamin is a vital player in energy metabolism, which means it is involved in the growth, development, and function of cells.1,2,3  Thiamin may also play a role in supporting cognition and nervous system health.1,2

Foods High in Thiamin

  • Thiamin is naturally found in many foods including beans, meat, nuts, and citrus fruit and juice.
  • One medium-sized orange (141 g) is a good source of Thiamin and provides 10% of the Daily Value*.
  • One half of medium-sized grapefruit (120 g) provides 4% of the Daily Value for Thiamin*. An 8-ounce glass of 100% grapefruit juice provides 8% of the recommended Daily Value.
  • One medium-sized tangerine or mandarin (109 g) provides 6% of the Daily Value for Thiamin*

Thiamin Requirements

Very little thiamin is stored in the body, and because it is used up quickly by the body, frequent consumption of thiamin from the diet is necessary. Thiamin needs increase during breastfeeding,1-3 and intake strongly affects the amount of this vitamin in breast milk.3 Requirements for thiamin also increase during:1-5
  • Strenuous activity
  • Pregnancy and breastfeeding
  • Acute illness or fever
  • Recovery after surgery

Thiamin Deficiency

Thiamin deficiency is rare. It is more common in people with specific medical conditions including alcoholism, Crohn’s and other digestive diseases, and anorexia.1-3 Deficiency in thiamin can affect the cardiovascular, muscular, digestive, and nervous systems.1-3 * Daily Value: Based on a 2000 calorie diet. FDA rounding rules applied when calculating percent DV based upon 2018 rules. Information is not intended for labeling food in packaged form. Nutrient values may vary based on brand or product types.

Thiamin was the first B vitamin scientists discovered, hence the name B1.1