NUTRIENT LIBRARY

Nutrient Library - Thiamin

Thiamin

What does it do?
How much do you need?
What are the best food sources?
What happens if you don’t get enough?
What happens if you get too much?
What are some recipes that are good sources of thiamin?
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What does it do?

Thiamin is a water-soluble B vitamin that helps your cells produce energy from carbohydrates. It is essential for the functioning of the heart, muscles and nervous system because it plays a role in conducting nerve impulses and in muscle contraction.

How much do you need?

The following table lists the recommended intake for healthy people based on current scientific information.

Life Stage Group	Recommended Dietary Allowance / Adequate Intake (see note below)	Tolerable Upper Intake Level (UL)
Infants	(milligrams/day)
0-6 mo. 7-12 mo.	0.2* 0.3*	Not determinable due to lack of data on adverse effects and concern about inability to handle excess amounts. Source should be from food only to prevent high levels of intake.
Children
1-3 yr. 4-8 yr.	0.5 0.6
Males
9-13 yr. 14-18 yr. 19-30 yr. 31-50 yr. 51-70 yr. > 70 yr.	0.9 1.2 1.2 1.2 1.2 1.2
Females
9-13 yr. 14-18 yr. 19-30 yr. 31-50 yr. 51-70 yr. > 70 yr.	0.9 1.0 1.1 1.1 1.1 1.1
Pregnancy
< 18 yr. 19-30 yr. 31-50 yr.	1.4 1.4 1.4
Lactation
< 18 yr. 19-30 yr. 31-50 yr.	1.4 1.4 1.4

NOTE: The table is adapted from the Dietary Reference Intakes reports. Recommended Dietary Allowances (RDAs), when available, are in bold type; Adequate Intakes (AIs) are followed by an asterisk(*). RDAs and AIs may both be used as goals for individual intake. RDAs are set to meet the needs of almost all individuals (97 to 98 percent) in a group. For healthy breastfed infants, the AI is the mean intake. The AI for other life stage and gender groups is believed to cover the needs of all individuals in the group, but lack of data means the percentage of individuals covered by this intake cannot be specified with confidence.
UL = The maximum level of daily nutrient intake that is likely to pose no risk of adverse effects. Unless otherwise specified, the UL represents total intake from food, water and supplements.

What are the best food sources?

Food sources of thiamin include enriched, fortified and whole-grain products, such as bread, rice, pasta, tortillas and cereals, and beef liver and pork. See more food sources and calculate your daily intake.

What happens if you don’t get enough?

Early symptoms of thiamin deficiency include fatigue, weak muscles, anorexia, weight loss and mental changes, such as confusion or irritability. As deficiency becomes more severe, it can result in a disease called beriberi, which is characterized by severe cardiovascular and nervous-system complications including cardiac failure in infants. Beriberi, which is most often observed in developing nations, was referred to in Chinese medical texts as early as 2700 B.C. (though at the time they didn’t make the connection between diet and disease).

Thiamin deficiency is rare in industrialized countries, where it usually only occurs in chronic alcoholics. In alcoholics, thiamin deficiency can progress to beriberi or Wernicke-Korsakoff syndrome, a disease most commonly a result of alcohol-induced malnutrition.

What happens if you get too much?

It’s not likely that you will experience adverse effects from consuming too much thiamin; your body absorbs less thiamin at intakes above 5 mg and excretes any amount it considers excess. Although documentation of adverse effects from excess thiamin is limited, this does not mean there is no potential for harmful effects, so stay within the range of recommended intakes.