What Are the Best Sources of Thiamin?

Vitamins are nutrients your body needs to carry out reactions that are essential for life but can’t make in sufficient amounts. To avoid a vitamin deficiency, you need to get adequate amounts of vitamins from dietary sources, preferably from unprocessed foods. Water-soluble vitamins need to be replaced frequently since they aren’t stored well by the body. Such is the case with the vitamin known as thiamin, also called vitamin B1. Thiamin stores can be depleted in as little as two weeks if you don’t get enough through diet.
 
What Are the Functions of Thiamin?
Thiamin plays a key role in energy metabolism. Specifically, it acts as a coenzyme in several key reactions involved in cellular energy production. It’s also plays a role in the synthesis of DNA and RNA, the genetic material inside cells that serves as blueprint for making the proteins your body needs to operate properly. It’s also involved in nerve function – although its exact role hasn’t been determined yet.
 
Needless to say, thiamin is a critical vitamin for good health because of its involvement with energy metabolism. After all, your body requires a constant supply of energy for long-term survival. What happens if you don’t get enough? A deficiency of thiamin leads to a condition known as beri beri. Symptoms of beri beri include severe muscle weakness, heart enlargement, fluid accumulation, and fatigue.
 
Beri beri is a disease that’s fatal unless thiamin stores are replaced through diet or supplements. A thiamin deficiency may also cause peripheral nerve damage characterized by tingling in the legs and feet as well as muscle weakness. Thiamin deficiency symptoms can occur in as little as one week of consuming no thiamin.
 
What are the Best Food Sources of Thiamin?
You can find thiamin a variety of foods, although not always in high concentrations. The best food sources are pork, beef, chicken, sunflower seed, bran flakes, and whole grains. Processed grains have lower levels of thiamin than whole grain foods unless the vitamin is added back in through fortification. Vegetables, fruits and dairy products typically have low levels of thiamin. Thiamin is fragile when exposed to heat, so cooking foods to high temperatures can destroy it. Some thiamin is also lost when foods are thawed. How much do you need? The recommended daily allowance of thiamin for adults is 1.4 milligrams.
 
What are the Causes of Thiamin Deficiency?
The most common reason for thiamin deficiency is alcoholism. Alcoholics don’t get enough thiamin in their diet nor do they absorb or metabolize it well. That’s unfortunate since alcoholics who are thiamin deficient can develop a more severe form of deficiency disease called Wernicke’s encephalopathy, a serious health condition characterized by mental status, vomiting, and abnormal eye movements. Wernicke’s can progress further to a form of dementia that may be permanent called Korsakoff syndrome.
 
People who have certain diseases of the digestive tract such as inflammatory bowel disease may absorb thiamin poorly and develop a deficiency as a result. Individuals with an eating disorder like anorexia nervosa are also at risk because they don’t consume enough calories to meet their thiamin requirements.
 
People who eat a diet high in refined carbohydrates like white rice are also at risk for thiamin deficiency since most refined carbs are a poor source of this vitamin.
 
Preventing Thiamin Deficiency
Are you getting enough thiamin? The best way to ensure you’re meeting your requirements is to eat a diet rich in unprocessed foods, whole grains, and lean protein on a daily basis.  Avoid empty calories that offer little or no nutritional value.
 
References:
The Nutritionist. Robert Wildman, PhD, RD. 2002. pages 204-209.
Merck Manual. 18 th edition.
 
Short Summary:
Your body needs thiamin, also known as vitamin B1, for health. A deficiency of this vitamin can have serious consequences. How do you know if you’re getting enough? Learn more about the best sources of thiamin and the consequences of not getting enough.