• Thiamine (B1)

    image Thiamine, also called vitamin B1, is a water-soluble vitamin found in virtually every cell in the body. Water-soluble vitamins are stored in the body in very limited amounts and are excreted through the urine. For this reason, it is a good idea to have them in your daily diet. Thiamine is also available as a supplement and by prescription as an injection.


    Thiamine helps to process carbohydrates, fats, and proteins. Specifically, it is needed to make adenosine triphosphate, or ATP, the body’s main energy-carrying molecule. Thiamin is also necessary for memory and other brain functions.

    Recommended Intake

    Age Group Recommended Daily Allowance (RDA)
    Females Males
    0-6 months 0.2 Adequate Intake (AI) 0.2 (AI)
    7-12 months 0.3 (AI) 0.3 (AI)
    1-3 years 0.5 0.5
    4-8 years 0.6 0.6
    9-13 years 0.9 0.9
    14-18 years 1.0 1.2
    19 and older 1.1 1.2
    Pregnancy and Lactation 1.4 n/a

    Thiamin Deficiency

    Thiamine deficiencies are rare in the United States because thiamine is added to refined grains. However, deficiencies do sometimes occur. Symptoms of thiamine deficiency include:
    • Fatigue
    • Weak muscles
    • Muscle ache
    • Dizziness
    • Low blood pressure
    • Numbness and tingling in arms and legs
    • Nausea and vomiting
    • Anorexia
    • Constipation
    • Depression or mood swings
    Thiamine deficiency was more common before thiamine was added to refined grains. This deficiency can lead to beriberi, a disease that affects the cardiovascular, gastrointestinal , and nervous system.

    Thiamin Toxicity

    There have been no adverse effects reported with taking too much dietary thiamine—the body excretes any excess amount that is consumed. In rare instances, coughing, hives, itching swelling, and breathing difficulties have occurred from thiamine injections given by doctors.

    Major Food Sources

    Thiamine is mostly found in whole-grain and enriched grain products like bread, pasta, rice, and fortified cereals. These foods are enriched with thiamine because the vitamin is often lost during the refining process. Pork, liver, and other organ meats are naturally high in thiamine. This table lists good food sources of thiamine.
    Food Serving Size Thiamin Content
    Spirulina seaweed 3.5 oz 2.38
    Ham, cured (4-5% fat), roasted 3.5 oz 1.03
    Pork, lean, roasted 3.5 oz 0.58
    Bagel, 3.5” (plain, egg, onion, or poppy seed) 1 bagel 0.38
    Catfish, farm-raised 3 oz 0.36
    Pita bread, white 1 pita 0.36
    Baked beans 1 cup 0.34
    Pinto beans 1 cup 0.32
    Salmon, Atlantic, cooked 3 oz 0.29
    Sun dried tomatoes 1 cup 0.29
    Kidney beans, red, boiled 1 cup 0.28
    English muffin 1 muffin 0.25
    Potato, baked 1 medium potato 0.24
    Cassava, raw 3.5 oz 0.23
    French beans, boiled 1 cup 0.23
    Pineapple, canned 1 cup 0.23
    Orange juice, fresh 8 fl oz 0.22
    Tomato paste, canned ½ cup 0.20
    Trout, farm-raised 3 oz 0.20
    Avocado 1 medium avocado 0.19
    Brown rice, long grain, cooked 1 cup 0.19
    Yellow corn, boiled ½ cup 0.18
    Acorn squash, baked, cubed ½ cup 0.17
    Carrot juice, canned 6 fl oz 0.17
    Raisins, seedless 2/3 cup 0.16
    Mussels, blue 3 oz 0.14
    Oysters, canned 6 medium oysters 0.13
    Watermelon, raw 1 cup 0.13
    Mandarin oranges, canned ½ cup 0.10

    Health Implications


    A severe thiamine deficiency, though rare in the US, can cause the disease beriberi. Beriberi can damage the heart and the nervous system. Symptoms include fatigue, diarrhea, weight loss, memory loss, and heart failure. This condition is still seen in people who abuse alcohol, in people whose ability to absorb thiamine is impaired, and in developing countries where foods are not fortified. Treating beriberi with vitamin B1 cures most cases, though severe deficiency can cause irreversible damage.

    Korsakoff’s Syndrome

    A deficiency of thiamine can cause Korsakoff’s Syndrome, which mainly affects short-term memory. Symptoms of Korsakoff’s syndrome include difficulty with walking and balance, paralysis of some of the eye muscles, confusion, and drowsiness. It is often caused by alcoholism and also occurs with forms of brain damage, such as tumors , head injuries , and strokes. Treatment of Korsakoff’s syndrome involves intravenous thiamine and oral thiamine supplements over many months. If alcoholism is the cause, that also needs to be treated.

    Congestive Heart Failure

    In people with congestive heart failure (CHF), the heart's ability to pump weakens, and fluid begins to accumulate in the lungs and legs. Loop diuretics are often prescribed to treat CHF. However, these drugs can deplete the body of thiamine. Since thiamine is required for normal heart function, this can cause problems. Thiamine supplements may be prescribed in these cases.

    Conditions That May Increase the Need for Thiamine

    While thiamine deficiency in a healthy person is uncommon, there are conditions that can increase the need for thiamine, making a deficiency possible. If you have any of the following conditions, talk with your doctor about your thiamine needs:
    • Alcoholism
    • Long-lasting fever or illness
    • Intestinal disease
    • Diet high in simple carbohydrates (eg, candy, cake, soda, bread and pasta made with white flour, cereals)
    • Total parenteral nutrition
    • Eating disorders
    • Severe infection
    • Dialysis
    • Cancer
    • Pregnancy and breastfeeding
    • AIDS
    • Prolonged diuretic use

    Tips for Increasing Your Thiamin Intake:

    To help increase your intake of thiamin, add some of these to your diet:
    • Add sun-dried tomatoes and yellow corn to your favorite chili recipe.
    • Make a fruit salad with oranges, pineapple, orange juice, and watermelon.
    • Try Cajun catfish. Coat a catfish fillet with a little olive oil and sprinkle with flour, pepper, and Cajun seasoning. Broil or bake the catfish at 400°F until golden brown and fish flakes when tested with a fork (approximately 10-15 minutes).
    • Spread lox (smoked salmon) on a bagel. Start with light cream cheese on a bagel. Then add lox , lettuce, red onion, and capers.


    American Dietetic Association http://www.eatright.org/

    United States Department of Agriculture http://www.usda.gov/wps/portal/usdahome/


    Canadian Council on Food and Nutrition http://www.ccfn.ca/

    Dietitians of Canada http://www.dietitians.ca/


    Jordan J, Patel M, Jordan F, eds. Thiamine: Catalytic Mechanisms in Normal and Disease States. New York, NY: Marcel Dekker; 2003.

    Nutrition Fact Sheet: Thiamin (vitamin B1). Northwestern University website. Available at: http://www.feinberg.northwestern.edu/nutrition/factsheets/vitamin-b1.html . Accessed May 4, 2009.

    Thiamin. Alternative Med Rev. 2003;8:59.

    Thiamin. Linus Pauling Institute website. Available at: http://lpi.oregonstate.edu/infocenter/vitamins/thiamin/. Accessed April 13, 2011.

    Thiamin—B1. The World's Healthiest Foods website. Available at: http://whfoods.org/genpage.php?tname=nutrient&dbid=100. Accessed April 13, 2011.

    Revision Information

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