Thiamin, also called vitamin B1 or aneurine, was the first B vitamin ever discovered. This water-soluble vitamin is 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. Thiamin is also available as a supplement and by prescription as an injection.
Thiamin 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.
Daily Reference Intake (DRI)
0.2 Adequate Intake (AI)
19 and older
Pregnancy and Lactation
Thiamin deficiencies are rare in the United States because thiamin is added to refined grains. However, deficiencies do sometimes occur. Symptoms of thiamin deficiency include:
Thiamin deficiency was more common before thiamin was added to refined grains. This deficiency can lead to beriberi, a disease that affects the cardiovascular and nervous system.
There have been no adverse effects reported with taking too much dietary thiamin—the body excretes any excess amount that is consumed. In rare instances,
, itching swelling, and breathing difficulties have occurred from thiamin injections given by doctors.
Major Food Sources
Thiamin is mostly found in whole-grain and enriched grain products like bread, pasta, rice, and fortified cereals. These foods are enriched with thiamin because the vitamin is often lost during the refining process. Pork, liver, and other organ meats are naturally high in thiamin. This table lists good food sources of thiamin.
Ham, cured (4-5% fat), roasted
Pork, lean, roasted
Bagel, 3.5” (plain, egg, onion, or poppy seed)
Pita bread, white
Salmon, Atlantic, cooked
Sun dried tomatoes
Kidney beans, red, boiled
1 medium potato
French beans, boiled
Orange juice, fresh
8 fl oz
Tomato paste, canned
1 medium avocado
Brown rice, long grain, cooked
Yellow corn, boiled
Acorn squash, baked, cubed
Carrot juice, canned
6 fl oz
6 medium oysters
Mandarin oranges, canned
Populations at Risk for Thiamin Deficiency
The following populations may be at risk for thiamin deficiency and may require a supplement:
A severe thiamin deficiency, though rare in the US, can cause the disease beriberi. Beriberi can damage the heart and the nervous system. Symptoms include fatigue,
, weight loss, memory loss, and heart failure. This condition is still seen in people who abuse alcohol, in people who’s ability to absorb thiamin 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.
A deficiency of thiamin can cause
, 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
. Treatment of Korsakoff’s syndrome involves intravenous thiamin and oral thiamin 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 thiamin. Since thiamin is required for normal heart function, this can cause problems. Thiamin supplements appear to help.
Conditions That May Increase Need for Thiamin
While thiamin deficiency in a healthy person is uncommon, there are conditions that can increase the need for thiamin, making a deficiency possible. If you have any of the following conditions, talk with your doctor about your thiamin needs:
Add sun-dried tomatoes, French beans, or yellow corn to your favorite chili recipe.
Make a fruit salad with mandarin oranges, pineapple, raisins, orange juice, watermelon, and your other favorite fruits.
Slice an avocado. Add a little balsamic vinegar and pepper, and scoop out for a snack. Or, mash the avocado and mix with chopped tomatoes and red onions for a refreshing salsa.
Bake a potato. Poke holes in the potato and cook at 350°F for 45-60 minutes (or microwave for 6-8 minutes).
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 on a bagel. Start with light cream cheese on a bagel. Then add lox (smoked salmon), lettuce, red onion, and capers.
Please be aware that this information is provided to supplement the care
provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
advice of your physician or other qualified health provider prior to
starting any new treatment or with any questions you may have regarding a