Vitamin B1

Vitamin B1 is also called thiamine or thiamin.  One of the eight B vitamins, vitamin B1 plays a vital role in the metabolism by helping the body break carbohydrates down into energy.  It is called B1 because it was the first B vitamin to be recognized.  In fact, it was also one of the first organic compounds to be identified as a vitamin.  The Recommended Daily Allowance for thiamine is 1.2 mg per day for adult men and 1.1 mg per day for adult women.  Women who are pregnant or breastfeeding need slightly more.

Vitamin B1 and Your Body

Thiamine is present in most vitamin B complex supplements.  Sometimes called “anti-stress” vitamins, the B vitamins are often thought to boost the immune system and help the body cope with stressful situations. 

Thiamine is most effectively used for the treatment of beriberi (a disease caused by a thiamine deficiency), Wernicke-Korsakoff syndrome (a brain disorder often caused by malnutrition due to alcoholism), and certain metabolic disorders, including maple syrup urine disease and subacute necrotizing encephalopathy.  Thiamine may also help to prevent cataracts, heart failure, and kidney disease, but more research is needed in these areas.  People take thiamine for a wide range of additional conditions; however, most experts agree that more research is still needed to determine thiamine’s efficacy in these areas, which include preventing cervical cancer, boosting athletic performance, improving the appetite and other chronic digestive problems, supporting the immune system for people with AIDS, and enhancing the memory for people with Alzheimer’s.

Sources of Vitamin B1

Pork and organ meats (like liver) are rich sources of vitamin B1.   Other good sources of this vitamin include whole grains, legumes, wheat germ, blackstrap molasses, and brewer’s yeast.  In addition, white rice and many foods made with white flour are often fortified with thiamine.  Eating a varied diet should provide most people with adequate amounts of vitamin B1; it is prudent for anyone who is at risk for malnutrition (especially anyone who is institutionalized or elderly) to take a multivitamin supplement.

Signs of Vitamin B1 Deficiency

It’s unusual for people in developed countries to be deficient in thiamine; however, people with Crohn’s disease or anorexia, alcoholics, and people on kidney dialysis may display signs of thiamine deficiency, which include fatigue, depression, irritability, and abdominal pain.

Beriberi is a serious disease caused by thiamine deficiency.  There are two types: wet and dry beriberi.  Symptoms of dry beriberi (which affects the nervous system) include trouble walking, loss of sensation in the feet and hands, inability to move the lower legs, mental confusion, pain, nystagmus (unusual eye movements), vomiting, and tingling sensations.  Wet beriberi involves the cardiovascular system and may cause patients to awaken at night feeling unable to breathe, as well as increased heart rate, shortness of breath, and swelling in the legs.  It can be treated with thiamine injections or oral supplements.  When treated early enough, there is a good chance of full recovery, but failure to treat beriberi can be fatal.

Signs of Vitamin B1 Toxicity

Vitamin B1 is a water-soluble vitamin, so the body generally gets rid of any excess.