The Role of Thiamine Deficiency in Brain Disease
Not getting enough thiamin regularly can disrupt brain function. Your body keeps only small stores of thiamin around, so if you don’t get it regularly in food or supplements, your brain can get in trouble after only a few weeks of deprivation. Severe deficiencies of thiamin lead to brain damage, including something called Korsakoff’s psychosis (loss of memory, apathy, dementia) found most commonly among nutritionally-famished alcoholics.
BRAIN ALERT: A lack of thiamin is alarmingly widespread.
- About 40 percent of older Americans brought to hospitals have a thiamin deficiency, according to a 1999 study. One reason: Many are taking diuretic drugs that interfere with metabolism of thiamin.
- Some 22 percent of young men and 20 percent of young women showed borderline or fully deficient intakes of thiamin in a 1996 British study.
- Recent autopsies in Australia found that 2.8 percent of the population had distinct signs of brain damage of the type caused by thiamin deficiency.
It’s well known that a lack of thiamin can ruin your mood, according to a string of studies dating back to the 1940s. In a recent study of older Irish women, fully 65 percent were either deficient or marginal in blood levels of thiamin. After a six-week regimen of taking 10 milligrams of thiamin a day, the women definitely were less fatigued and had greater feelings of well-being.
Too little thiamin also lowers the spirits of younger people. A recent German study of 1081 young men found 23 percent low in thiamin. They were more apt to be introverted, inactive, fatigued, with low self-confidence, and diminished mood. When they took 3 milligrams of thiamin a day for two months in a double-blind test, they became more sociable and happier.
“The first response to a thiamin-deficient diet is an inability to concentrate, confusion of thought, uncertainty of memory, anorexia, irritability, and depression.” —R. D. Williams, Archives of Internal Medicine, 1942
THIAMIN AND DYSFUNCTIONAL BRAINS
The detrimental effects of marginal thiamin deficiencies on the brain has been known for decades. In the early 1940s, pioneering psychologist-researcher Ruth Harrell, then at Teachers College, Columbia University in New York, extensively investigated the impact of vitamins on children, especially those with poor diets. In one double-blind study, she gave thiamin supplements to eleven-year-old children in an orphanage who consumed a mere one milligram of thiamin daily. After a year, the children taking thiamin showed increases in reaction time, intelligence, visual acuity, memory, and reaction times.
More recently, in the 1980s, Derrick Lonsdale, M.D., then a researcher at the Cleveland Clinic Foundation specializing in pediatric and adolescent medicine, did red blood cell studies on more than 1000 patients, children and adults, and confirmed that 28 percent had a thiamin deficiency, often of long standing. The patients had been referred for various behavioral problems, such as hyperactivity, learning disability, tantrums, erratic temper, violent mood swings, depression, anxiety, and sleep problems.
Dr. Lonsdale routinely gave them a multivitamin-mineral supplement containing high doses of B vitamins, including thiamin, or thiamin alone. Their blood-cell thiamin became normal, usually within a few months, in nearly all cases. Remarkably, as their thiamin deficiency cleared up, their symptoms lessened or completely vanished. This, he said, “strongly suggests that the symptoms were caused by disturbed brain chemistry” of a type long attributed to thiamin deficiency. Lonsdale suggested that such patients actually had the early symptoms of beriberi, a nerve-damaging condition due to severe thiamin deficiency. He also concluded that “the surprisingly high incidence of abnormal tests revealed a widespread nutritional deficiency in the United States.”
He also tied the thiamin deficiency and behavioral problems to a long-time diet of “junk food,” including “empty” calorie soft drinks. In animals, he says, a high-sugar diet along with a thiamin deficiency is extremely threatening to brain functioning.
Undeniably, a lack of thiamin is common in youngsters. One British survey found that fully 49 percent of adolescent girls and 19 percent of boys consumed but one milligram of thiamin daily, suggesting a widespread deficiency severe enough to “cause psychological dysfunction,” in the words of Dr. David Benton.
Dr. Benton recently showed that a supplement of nine vitamins raised mood in a group of 129 young healthy men and women. After a year they said they felt more “agreeable” than those taking a dummy pill. The women also said they felt more “composed” and that their mental health had improved. Not surprisingly, as their vitamin blood status ally deficient in thiamin. In a double-blind test of 120 women, average age twenty, all showed normal blood levels of thiamin. Nevertheless, Dr. Benton wondered whether an extra high dose of 50 milligrams of thiamin daily would have an impact on mood. It did.
Thiamine takers said they were more clear-headed, composed, and energetic than before. They also had faster reaction times and made quicker decisions on a specific mental performance test. On the most difficult part of the test, the average microsecond reaction times of the thiamin takers quickened by about 13 percent, whereas reaction times of the placebo group remained about the same. The extra thiamin, however, did not improve memory in those with normal thiamin. Other research suggests it does improve memory in those who are thiamin deficient.
This does not mean everyone should take such super-high doses of thiamin. But it clearly indicates that the standard “normal” levels for thiamin may be insufficient for universal top brain functioning. The “normal” amounts that prevent overt symptoms of brain malfunction may not be enough to push the brain to its optimal feel-good and performance peaks.
BOTTOM LINE: Taking thiamin improves brain functioning even in normal healthy women who have no overt signs of a deficiency.
How could thiamin have such a powerful effect on the brain? According to Philip Langlais, Ph.D., professor of psychology at University of California, San Diego, Medical School, as quoted recently in Psychology Today, “A thiamin deficiency hampers the brain’s ability to use glucose, decreasing energy available for mental activities. It also overexcites neurons so that they fire endlessly, poop out, and die.
“If you are even marginally deficient in thiamin,” said Langlais, “you may be slowing down your brain power.”
How much? Even the amount of thiamin in multivitamin supplements should be enough to prevent a deficiency. Some experts favor 25 milligrams a day to be sure. Even in high doses thiamin seems harmless, but experts put a “safe dose” at no more than 50 milligrams per day.