Taking thiamine by mouth may help some complications of metabolic disorders associated with genetic diseases. These include: Leigh's disease (a nervous system disorder causing movement problems), maple syrup urine disease (protein breakdown disorder in which urine smells like maple syrup), pyruvate carboxylase deficiency (rare disorder causing developmental problems in babies), and high blood levels of alanine, an amino acid. Long-term management should be under strict medical supervision.
Humans depend on diet for their thiamine needs. Very little thiamine is stored in the body and depletion can occur within 14 days. Severe thiamine deficiency may lead to serious complications involving the nervous system, brain, muscles, heart, and stomach and intestines. Thiamine deficiency can be associated with alcoholism, poor nutrition, cancer, vomiting associated with pregnancy, bariatric surgery, and hemodialysis. Some people may be more at risk of thiamine deficiency. Those with thiamine deficiency or related conditions should receive supplemental thiamine under medical supervision.
Alcoholics or those experiencing alcohol withdrawal are at risk of thiamine deficiency and its associated complications. Thiamine has been injected into the vein with other nutrients. Further research is needed on the impact of thiamine on alcoholism.
Total parenteral nutrition (TPN)
Thiamine has been added to total parenteral nutrition (TPN, nutrition given through the veins) for people who cannot receive thiamine by mouth, such as a multivitamin.
Thiamine deficiency can result in a form of dementia. The relationship of thiamine to Alzheimer's disease and other forms of dementia has been studied. However, there is still controversy over whether thiamine supplementation may benefit people with Alzheimer's disease. More research is needed before a firm conclusion can be made.
Thiamine-responsive megablastic anemia (TRMA) is a genetic disorder that affects thiamine transport and conversion in the body. Thiamine has been studied for heart problems associated with TRMA, as well as other TRMA symptoms. More information is needed in this area.
Active people who reduce food intake may have a higher risk of vitamin deficiency, including thiamine deficiency. More research is needed in this area.
Blood vessel clots
B vitamins have been studied for the treatment of clots in blood vessels. Further research is needed in order to form conclusions.
Thiamine deficiency has been seen in some people with cancer, possibly due to medication use or poor nutrition. Currently, it remains unclear whether thiamine supplementation may benefit any particular types of cancer. Supplementation may be needed in people with cancer who have or are at risk of thiamine deficiency.
Early evidence suggests that high dietary thiamine intake may help reduce the risk of cataracts. Further study is needed before a firm conclusion can be made.
Cerebellar ataxia (movement disorder due to brain cell damage)
Early research suggests that thiamine supplementation may benefit people with cerebellar ataxia after an illness involving fever. Further research is needed.
Blood sugar imbalances may increase the risk of clogged arteries. Thiamine has been studied as a way to help widen narrowed arteries. Regular thiamine intake may improve blood vessel function and slow the progression of clogged arteries in people with blood sugar imbalances. Further study is needed.
Coma/hypothermia of unknown origin
Thiamine is often recommended in people with coma or hypothermia (dangerously low body temperature) of unknown origin. Thiamine has been studied in people with reduced consciousness due to poisoning. More research is needed.
Low thiamine levels have been reported in people with Crohn's disease (a form of inflammatory bowel disease). It is not clear whether regular thiamine intake may benefit people with this disease in general.
Thiamine has been studied for complications associated with diabetes, involving the nervous system, eyes, blood vessels, and kidneys. Thiamine may improve complications such as increased urination, high levels of glucose in the urine, and high blood cholesterol levels. Regular thiamine intake may also help slow the progression of clogged arteries in some diabetics. More research is needed in this field.
Early research suggests that thiamine may improve attention and mental function in people who have epilepsy. Further research is needed.
Long-term thiamine deficiency may cause heart failure, which requires thiamine supplementation. It is unclear whether thiamine supplementation may benefit people who have heart failure due to other causes. However, it is reasonable for those with heart failure to take a daily multivitamin including thiamine. More evidence is needed before a firm conclusion can be made.
Vitamin deficiency, including thiamine deficiency, has been linked to long-term kidney dysfunction. Taking a multivitamin is often suggested. However, further research is needed in this field.
Vitamin B supplements have been used to treat leg cramps during pregnancy. However, more studies are needed to determine if this is effective.
Early evidence suggests that thiamine may be effective for menstrual cramps. Further research is needed to confirm these results.
Thiamine has been studied as a treatment for mitochondrial disorders, which occur when there are defects in the mitochondria (a part of the cell that produces energy). More research is needed before conclusions can be made.
Pyruvate dehydrogenase deficiency (PDH)
PDH is a disorder caused by the buildup of lactic acid, which may be life-threatening and cause nervous system problems. Early evidence suggests that thiamine supplementation may benefit children with PDH. Further evidence is needed before a firm conclusion can be reached.
Rheumatism (joint problems)
Early evidence suggests that B vitamins may reduce pain. Further research is needed to determine the effectiveness of thiamine in rheumatism and related disorders.
Temporomandibular joint disorder (TMJ)
TMJ is a disorder of the chewing muscles and joints. A combination of indomethacin and thiamine has been studied for this condition, but was found to be less effective than acupuncture. More research is needed in this field.
Thiamin deficiency (elderly people)
Thiamine levels may be lower in elderly people, although there is typically a lack of symptoms. There is limited evidence that thiamine supplementation may benefit people who have low thiamine blood levels. However, general multivitamin use has been suggested in elderly people. More research is needed before a firm conclusion can be made.
Early evidence shows that thiamine lacks benefit for hip fractures. However, research is limited and further study is needed.