You’ve probably heard of thiamine, another name for vitamin B1, possibly in relation to “fortified” foods like cereals and breads. As one of eight essential B vitamins, thiamine is considered “essential” because your body can’t produce it on its own; it must come from an outside source.
Mostly concentrated in the skeletal muscles, but also found in your brain, liver, kidneys and heart, it’s excreted by the kidneys 1 and performs several important functions in your body. More than one study has suggested it to be the primary “B” needed on a day-to-day basis.
Thiamine is used by nearly all your cells, metabolizing the carbohydrates and lipids in the foods you eat, helping to convert food into energy and boosting the flow of electrolytes in and out of the cells of your nerves and muscles. 2 There are different forms of thiamine, each with individual functions:
- Thiamine hydrochloride — The salt structure of thiamine, “essential for aerobic metabolism, cell growth, transmission of nerve impulses and acetylcholine synthesis,” is also responsible for forming thiamine pyrophosphate (TPP) needed for several enzymatic activities involving fatty and amino acids and carbohydrate metabolism. 3
- Thiamine pyrophosphate — The biologically active form in your body functions as a coenzyme in carbohydrate metabolism 4
- Thiamine mononitrate — The type typically used to make supplements
Organic Facts 5 lists a number of health benefits that are often overlooked in regard to having healthy levels of vitamin B1 in your system, such as:
- The oxidation of sugar due to a combination of enzymes known as pyruvate dehydrogenase complex
- The proper development of protective myelin sheaths around nerves
- The delay or prevention of cataracts
- The secretion of hydrochloric acid for optimal digestion
- Improved appetite
It’s sometimes called the “antistress” vitamin for its positive influence on your central nervous system.
What Happens When You Don’t Have Adequate Thiamine?
According to a study in 2013, 6 a long list of problems can occur when your body either doesn’t produce enough or doesn’t get enough nutritional benefit from food or through supplementation, and that includes thiamine. Constipation is something people with a thiamine deficiency often experience, but conversely, increasing their thiamine levels reduces the problem.
Thiamine is extremely important for cognitive function, as well as your nervous system and red blood cell formation, so it only stands to reason that it’s vital for brain health. When thiamine is missing or low, a whole string of such functions can be damaged in a sort of domino effect.
For example, enzymes (such as pyruvate dehydrogenase complex) needed as a cofactor in the Kreb’s cycle and for synthesizing and breaking down excess levels of dopamine, can lead to diminished brain function. Impaired neurotransmitters such as gamma aminobutyric acid (GABA) can initiate problems like hallucinations, delusions and severe cognitive impairment. 7 The study explains:
“GABA is a major inhibitory neurotransmitter in the brain, and a decrease in the levels of this neurotransmitter and an increase in its amino acid precursor, glutamine, leads to neuronal excitation and hence delirium.” 8
Although eating foods containing thiamine may be the best way to support your system, sometimes supplying it more quickly may be in order. The cognitive dysfunction noted earlier in relation to a vitamin B1 deficiency can be remedied with supplementation, as noted in one study 9 in which 120 young adult females, whose levels were “adequate,” were given either the vitamin or a placebo daily for 60 days.
Beforehand, the participants’ mood, memory and reaction times were monitored; afterward, those who received B1 reported being “more clearheaded, composed and energetic,” and their reaction times were faster.
Thiamine Deficiency and Life-Threatening Results
Although it’s not seen as often today as it has been in the past, a disorder known as beriberi is caused by low levels of vitamin B1. There are two types: “wet” beriberi, which damages the circulatory system and can cause heart failure, and “dry” beriberi, which results in nerve damage, diminished muscle strength and eventual muscle paralysis. Needless to say, it can be a life-threatening condition.
Beriberi is sometimes linked to Wernicke-Korsakoff syndrome, an amalgamation of Wernicke encephalopathy and Korsakoff syndrome, which, according to HealthLine, 10 are two forms of brain damage in the thalamus and hypothalamus regions that are directly related to thiamine deficiency.
Wernicke encephalopathy can bring about confusion, memory loss, reduced muscle coordination and vision problems like rapid eye movement and double vision. Korsakoff syndrome is a sign of permanent damage in the memory-storage areas of the brain; symptoms can include both memory loss and an inability to form new memories, as well as hallucinations.
Again, while the cause of this condition is a diet low in thiamine, it’s very rare in areas where people have access to fortified foods. It’s most common in regions of the world where the typical diet includes unenriched, processed white rice, as it has only a tenth of the thiamine in brown rice. (Like other foods, rice has both good and not-so-good elements; wild rice is the variety with more nutrients, fewer calories and fewer carbs, compared to white rice.)
One extensive review asserts, “Several risk factors can contribute to thiamine deficiency in patients with and without heart failure, such as inadequate dietary intake, excess alcohol ingestion, malabsorption syndromes and medications.” 11 The medications include diuretics, penicillins, tetracyclines (for infections), sulfonamides (antibiotics or for treating ulcerative colitis 12 ) and trimethoprim (used for bladder infections, middle ear infections and travelers' diarrhea 13 ).
The review also shows that patients with congestive heart failure (CHF), numbering around 5 million people in the U.S. alone, can benefit dramatically from thiamine supplementation, especially since deficiency ranges from between 21 percent and 98 percent, plus, the usual treatment alternatives are problematic:
“Although therapies for CHF — including angiotensin-converting enzyme inhibitors, beta-blockers, loop diuretics and omega-3 fatty acids — have improved morbidity and mortality, mortality rates in patients with CHF remain high … A 1995 trial indicated that thiamine supplementation in patients with CHF significantly improved left ventricular ejection fraction.” 14
Best Sources of Thiamine in Foods — With Caveats
Fortunately, thiamine is found in a variety of foods. Omitting the many packaged foods thiamine is used in, such as crackers, cereals and bread, “real” foods with the highest amounts include macadamia and pistachio nuts, flaxseeds and sunflower seeds, raw, organic, grass fed milk , vegetables like eggplant, asparagus and bell peppers, grass fed beef, watermelon and oranges.
According to the George Mateljan Foundation, 15 a nonprofit organization focusing on nutrition and the healthiest ways to cook for optimal health, around 20 percent of people in the U.S. over age 2 are deficient in vitamin B1. The site also lists crimini mushrooms, oats, garlic, parsley, cumin and sea vegetables as being sources of thiamine, as are kidney, black, pinto, navy and lima beans.
However, beans also contain sugar-binding proteins called lectins known to be a factor in leaky gut syndrome, which, among other problems, prevents the nutrients in the foods you eat from being adequately absorbed. For that reason, measures to keep lectins from ruining your gut, but still getting their nutritional benefits, involves a few important steps:
- Soak the dry beans for 12 hours prior to cooking, adding baking soda to the water
- Drain the water and rinse the beans thoroughly
- Add fresh water and cook the beans on high heat for a minimum of 15 minutes, as low heat can increase the lectin toxicity as much as five times over
How a Thiamine Supplement Can Help Alleviate Diseases and Disorders
There’s plenty of evidence showing the wide array of benefits that come from this vitamin. On the other hand, certain diseases, including diabetes, gastrointestinal ailments and heart failure, bring with them an increased risk of vitamin B1 deficiency.
Interestingly, increasing your thiamine intake to optimal amounts can prevent some of the worst symptoms and complications that are common consequences. Verywell Health 16 and University of Michigan Health 17 list several disorders and diseases this supplement may help treat:
Thyroid and Hashimoto’s disease
Advanced glycation end products, aka AGEs, are glycotoxins in high-fat meats that can trigger inflammation and speed up the damage done by degenerative, age-related diseases.
One study 18 indicates that benfotiamine (a fat-soluble form of thiamine) supplements were given to 13 participants with Type 2 diabetes, and after three days, they were given a meal high in AGEs (54 grams of protein and 48 grams of carbs). Subsequent tests showed that the supplement appeared to protect the study subjects from oxidative stress.
Additionally, in two randomized, double-blind, placebo-controlled trials of thiamine supplementation in patients with congestive heart failure, thiamine supplements compared to the placebo resulted in significant improvement.
As another study shows, thiamine deficiency was once a widespread problem in many Asian countries due to the nearly exclusive use of polished rice (i.e., white rice) as a staple diet, but once this was discovered, it was “somewhat controlled,” until recently:
“However, it is now realized that a large number of certain populations may be at high risk for developing this deficiency, including (heart failure); therefore, the interest in thiamine and thiamine deficiency has recently been reemerging …
Patients with (heart failure) may be at risk for developing certain micronutrient deficiencies, including thiamine deficiency. The focus of management of (heart failure) may need to be broadened to include the normalization of these nutritional abnormalities. Patients with (heart failure), especially those in advanced stages, may benefit from regular thiamine supplementation.” 19
Thiamine and Alcohol Consumption
Something else to take into consideration, especially for anyone who drinks alcohol, is that alcoholic beverage consumption is one of the leading causes of thiamin deficiency. What does a person’s alcohol intake have to do with their thiamine levels? On one hand, treatment with thiamine can help restore normal body function, but abuse is a slippery slope. According to the George Mateljan Foundation:
“Perhaps the most important and well-known inhibitor of vitamin B1 nutrition in humans, however, is alcohol abuse. Alcoholics use more vitamin B1 in the detoxification of alcohol, often eat less vitamin B1 due to poor dietary habits, have trouble absorbing vitamin B1 in the intestine, and urinate out more of the vitamin. This is an almost perfect scenario for increasing deficiency risk.” 20
The American Academy of Neurology reported in 2003 that individuals with certain “deficiencies in the hippocampus,” including thiamine, may result in Korsakoff syndrome, a memory disorder often found in alcoholism with symptoms comparable to the ravages of Alzheimer’s disease. In fact, “Greater hippocampal damage was correlated to a higher memory deterioration index score for the Korsakoff's patients.” 21
Study author Edith V. Sullivan, of Stanford University School of Medicine in California, noted both clinical and radiological similarities between the two disorders. In spite of the controversy involved, she believes that while their overall profiles are different, the nature of the impairments are the same. She notes:
“Resulting from a lack of thiamine (vitamin B1), Korsakoff's syndrome is typically a consequence of chronic alcohol dependence. Individuals at risk include those with nutritional deficiency disorders like anorexia. The nutrient thiamine helps restore certain brain functions like recalling past events and storing new information.
Current treatment of Korsakoff's patients includes thiamine and other B-complex vitamins. If treated early enough, Korsakoff's patients may have at least partial recovery.”
In addition, Sullivan stated in the study that clinicians who diagnose and treat patients with dementia should consider Korsakoff syndrome as they’re dialing in on a diagnosis.
Questions, Answers and Discussions Regarding Thiamine
If you think you may have a thiamine deficiency but you love to eat raw fish and shellfish, it’s important to note that both contain chemicals that can destroy the presence of thiamine in your body, so both should be avoided. However, cooked seafood dishes are not a problem in this regard.
Additionally, the tannins in tea and coffee may prevent your body from absorbing vitamin B1 properly. Also, it might be helpful to know that overcooking and refrigerating thiamine-containing foods for long periods can diminish or destroy the benefits of the vitamin.
What’s the difference between thiamine and the dietary supplement benfotiamine? 23 Benfotiamine is fat-soluble, as opposed to the water-soluble thiamine form, and therefore raises thiamine levels in your blood up to five times better, maintains those levels much longer and has both greater bioavailability and absorption by the body than water-soluble thiamine.
As is true with many good things, too much thiamine can cause problems, too, 24 starting with symptoms like blue lips, excessive sweating, restlessness, nausea and a mild rash or itching. More serious side effects from too much of this vitamin can fast-track to chest pain, shortness of breath, coughing up blood or vomit that looks like coffee grounds, and/or black, tarry stools. 25
How much thiamine do people need? According to Innovations in Clinical Neuroscience, the daily recommended thiamine intake for adult women is 1.1 milligrams (mg), and 1.2 mg for adult men. Children, typically having lower requirements, should get 0.5 to 1.2 mg per day, depending on their age and gender. Slightly higher levels of 1.4 mg per day are recommended for pregnant and/or breast-feeding women. 26