Thiamin is needed daily to preserve brain function. This water-soluble vitamin, sometimes referred to as vitamin B1, is found in whole-grain cereals, some legumes, pork chops, watermelons, acorn squash and yeast. The recommended daily intake for thiamin is 1.1 mg for women and 1.2 mg for men. Thiamin---or the lack of thiamin---affects brain function in numerous ways.
Neurotransmitter Function
You need thiamin so that some of your brain chemicals, which are called neurotransmitters, work properly. One of these neurotransmitters is called acetylcholine, and it is used in the memory-making and thinking areas of your brain, according to the Alzheimer Society of Canada. Thiamin affects the synthesis of acetylcholine within the body, leading to a change in acetylcholine levels, notes Harris R. Lieberman and colleagues in the book "Nutritional Nuroscience." This change is what causes a decrease in brain function. Other neurotransmitters are also affected by thiamin, including dopamine and serotonin, according to Lieberman.
Enzyme Function
Some enzymes in your brain depend on thiamin in order to carry out their activities, such as brain energy metabolism. One that specifically depends on thiamin is alpha-ketoglutarate dehydrogenase. When this particular enzyme does not work properly, you may suffer neuron loss. Thiamin deficiency also may lead to oxidative stress, which also causes neuron loss, according to Roger F. Butterworth's analysis published in the journal "Nutrition Research Reviews." Butterworth says this is significant, as decreased activity of these enzymes has been linked to Alzheimer's.
Avoiding Brain Damage
A steady supply of thiamin is needed to avoid brain lesions, according to "Nutritional Neuroscience." Your body does not store much thiamin. Also, only a limited amount of the thiamin in your body can reach your brain due to your blood-brain barrier. Thus, taking in an adequate daily supply of this vitamin is crucial to avoiding brain damage. Such damage is called Wernicke-Korsakoff syndrome. Symptoms of the first stage, called Wernicke's encephalopathy, include confusion, loss of balance, abnormal eye movements and lack of muscle coordination, according to the Mayo Clinic. In the first stage, you may be able to ward off long-term brain damage with treatment and lifestyle changes, such as cutting alcohol use. In the second stage, referred to as Korsakoff syndrome, your symptoms become chronic due to lasting brain damage. This stage is characterized by an inability to lay down new memories, according to the Mayo Clinic.
Avoiding Beriberi
You also need thiamin to avoid beriberi, the technical name for thiamin deficiency, according to Butterworth. There are two types of this disorder. Dry beriberi affects your nervous system. The impairment will affect the farthest out segments of your limbs more so than the areas that are closer to the point where your limb attaches to your body. You also may have exaggerated reflexes and weakness in your arms and legs, along with muscle tenderness, according to "The "Handbook of Food Science, Technology and Engineering" by Yiu H. Hui.
Wet beriberi also affects your cardiovascular system. It is characterized by neuron loss, congestive heart failure, edema, rapid heartbeat and an enlarged heart, advises Butterworth. With wet beriberi you also suffer peripheral neuropathy, which can cause numbness in your hands or feet, according to the Mayo Clinic.
When beriberi leads to abnormal eye movements, mental function abnormalities like confusion and issues with gait or stance, it is likely to lead to Wernicke-Korsakoff syndrome, Hui advises.
References
- "Nutrition Research Reviews;" Thiamin deficiency and brain disorders; Roger F. Butterworth; 2003
- Mayo Clinic: Peripheral neuropathy
- "Psychopharmacology---4th Generation of Progress"; Brain Energy Metabolism; Pierre J. Magistretti, Luc Pellerin and Jean-Luc Martin; 1995
- Alzheimer Society of Canada: Drug Treatments
- The Merck Manuals Online Medical Library: Thiamin: Vitamin Deficiency
