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Vitamin B-1

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Thiamine (also spelled thiamin) is a vitamin, which simply means that it is vital to life. Like all vitamins, it must be ingested as part of the diet of all living organisms. Some microscopic one cell organisms and plants are able to synthesize it. It is noteworthy that, although it was recognized as early as 1897 that there was a naturally occurring "anti-beriberi substance" in rice polishing, its chemical structure was not determined until 3 decades later and it was synthesized in 1938. The fundamental role of the vitamin in its various forms is to enable oxygen to be used in the process known as oxidative metabolism, whereby energy is produced for cellular function.


Thiamine pyrophosphate is a cofactor in at least 24 different enzymes, but its most important role is as an enzyme which enables glucose to be used as a fuel. Thiamine triphosphate has its most important role in brain and nerve tissue and this is quite different from the other roles that the vitamin plays. It appears to have a vital part in energizing nerve tissue in order that normal messages can be transmitted through the entire nervous system. Since the nervous system is the most metabolically active tissue in the body, this high energy compound has a crucial place in governing the high consumption of oxygen which is the hallmark of metabolic rate.

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This vital substance stands astride the mechanism by which glucose is used as fuel to deliver energy for cellular function. It can be compared to a spark plug in an internal combustion engine, but energy metabolism in mammalian cells has an incredible complexity and our knowledge of this has increased greatly in recent years. Thiamine illustrates this complexity, for one of the most important molecules in the cells is phosphate. When phosphate is added to a biologic substance it provides it with a means of storing energy. The main storage of energy in cells is in the form of adenosine triphosphate, which means that it possesses a high energy potential in electrochemical terms. A lower energy potential would exist in adenosine diphosphate and lower again in monophosphate. Thiamine works in a similar manner. It is "energized" by adding one, then two and finally three phosphate molecules. In each of these different forms the vitamin has a separate and different action in cell chemistry. It must be understood that energy can only be stored by using energy. Put simply, work has to be done (energy utilization) in order to pull back a bow string. The energy is stored in the form of the taut string and the arrow is shot from the bow at the will of the archer, by releasing the bow string. The bow string can be compared to both adenosine and thiamine in its lower or higher energy state. When energy is required for cell function, a phosphate is yielded and the adenosine or thiamine drops down to a lower energy potential. This transfer results in the release of energy which accomplished work.

Unphosphorylated thiamine is called "free thiamine" and appears to have no biologic activity at all. When it is in the form of monophosphate its function is poorly understood. It is best known in its diphosphate or pyrophosphate form, for it is used to energize a large number of enzyme systems in the body. An enzyme is a protein which acts as a catalyst in synthesizing a new molecule by a chemical reaction with another molecule, and this action requires energy. Part of this energy is derived from a vitamin or mineral which is known as a cofactor to the enzyme.

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A blood test known as transketolase is capable of revealing a state of thiamine deficiency with precision, and clinical experience finds that the test is frequently positive.

It is well known that alcoholics frequently become thiamine deficient. There are several reported conditions in which thiamine dependency exists. A vitamin dependency is a condition where an enzyme requires a much greater concentration of the vitamin as a cofactor than is usually required. Thus the normal RDA is totally insufficient, and the patient will develop symptoms which are identical to those seen in nutritional deprivation.

The message provided by Mother Nature is quite clear. We must continually adapt to the stresses of environment that beset us. If we fail to do so we become sick. If the failure is complete, we die. Vitamins and minerals are the catalysts in the union of oxygen with food (fuel) to provide the energy to drive the adaptive response. This explains the fact that we are unable to live without any one of these three essential components. Thiamine is one of the vitamin team, no less and no more essential than the others.


Tea contains a substance antagonistic to thiamine, and there are several molecules which block its action, such as pyrithiamine and oxythiamine. The most important naturally occurring substances which destroy the molecule are a pair of enzymes known as thiaminases 1 and 11. Both are produced by a number of bacteria which are found in human bowel and also are found in some shellfish and the intestines of other ocean fish. All these substances have been largely ignored as a potential for human disease.

Thiamine, like other vitamins, can enhance the effectiveness of drugs, so that normal pharmaceutical dose of a drug may cause symptoms of toxicity.

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It is relatively easy to understand that the most metabolically active organs suffer when there is a deficiency of this vitamin, since there is a high rate of oxygen consumption where there is a fast metabolic rate. Therefore it is not surprising to find that the classic thiamine deficiency disease in man is beriberi, a disease which affects the heart and nervous system most. However, beriberi is not due to pure thiamine deprivation; it is seen commonly in people whose diet is predominantly white rice and is still occurring in poorly nourished populations. Therefore it is most probably that there is a variable degree of vitamin deficiency in general. The key factor is the high calorie, exclusively carbohydrate diet, and thiamine is closely linked to metabolism of this dietary component. But other vitamins and minerals are required in addition because these substances are members of a nutritional team and must work together in order to use oxygen efficiently in energy metabolism.

Experimental thiamine deficiency has been induced in human subjects, a very risky procedure. The interesting thing about this experiment is that the effect on the experimental subjects was that they developed symptoms which are conventionally considered to by psychologic and psychosomatic. They became irritable, quarrelsome, difficult to live with, and complained of headaches, abdominal pain, nausea, diarrhea, constipation and many other symptoms indicating an unbalanced, irritated nervous system. It is unusual today for a physician or a psychologist to consider the possibility of faulty nutrition as a cause of psychologic illness. But psychoanalysis or tranquilizers cannot correct such symptoms if they have a biochemical origin.

In this connection it is of extreme importance to emphasize that any form of physical or mental stress will exacerbate symptoms. Hence it is easy to become misled in interpreting the cause of such symptoms. Obviously, if the metabolic engine is abnormal, it will cause abnormal effects in the nervous system which then expresses itself in abnormal behavior. It is not the stress that produces the effect merely because it is stress, any more than a steep hill can be blamed for causing an internal combustion engine to falter in an automobile that is climbing it. Either there is something basically wrong with the engine, or it is being provided with the wrong fuel to meet engine specifications.

This factor was responsible for a mistake that was made for a long time in beriberi. Among the Chinese factory workers there was widespread nutritional deficiency which could be relatively silent as far as symptoms. In the early part of the summer when they felt the first heat of the sun, beriberi would suddenly emerge as heart failure or nerve paralysis in many people at the same time. It was natural to think of an infectious epidemic as the cause and many physicians in those days thought this way. It was just as difficult for the early discoverers of vitamins to persuade their medical colleagues that diseases like beriberi, pellagra and scurvy were caused by malnutrition as it is today to emphasize that nutritional disease is still with us.

The point is made again, because it cannot be overstated, is that oxidation of calorie-providing food must be matched to the presence of sufficient vitamin and mineral spectrum. If the calorie load is disproportionate it is very much like choking an internal combustion engine. The mixture is too rich! Stressing the "engine" under these circumstances calls upon increased utilization of stored energy. The inability to provide it represents "the last straw to break the camel's back" and the disease emerges as the evidence.

A major question here is whether classic deficiency disease of this type exists in developed countries, and in America in particular. The answer, unfortunately, is that it does, but rarely in its fully developed state as described in medical textbooks of yesteryear.


Because of the structure of the molecule, the toxic action is similar to the drug known as hexamethonium which is used for the treatment of high blood pressure. It acts by causing an inhibitory action on certain nerve terminals. Oddly enough, the symptoms of thiamine deficiency are similar to those produced by an excessive amount ingested.

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The average physiologic requirement of thiamine is about 0.5 mg per 1,000 calories ingested, giving the equivalent of 1.5 mg per day. An active man might require 2.0 mg per day. However, the body is incapable of storing the vitamin in its free form and it can become biologically inactivated under stress so that large amounts can be lost in the urine. A diet with an excess of refined carbohydrates increases the demand considerably, as does a high stress level.

RDAs for:

Adult Males - 1.5 mg

Adult Females - 1.1 mg

Children 7 to 10 years - 1.0 mg

Infants - 0.4 mg

Pregnant and Lactating Women - 1.6 mg

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Thiamine is present in high concentration in yeast and in the pericarp and germ of cereals. It is present in practically all plant and animal tissues. Polished rice contains only 0.03 mg per 100 g, whereas whole rice contains 0.5 mg per 100 g and rice bran 2.3 mg per 100 g, illustrating the dietary importance of the part of the plant which is frequently discarded. The vitamin is also found in whole meal wheat flour and is almost nonexistent in white flour.

It is a water soluble, white crystalline solid which is oxidized by potassium ferrocyanide in the presence of alkali to a blue pigment called thiochrome. This is a basis for detecting the presence of the vitamin in urine. It is surprisingly stable, even when heated as in cooking, if it is in the crystallized state or in an acid solution. It is less stable in alkaline solution and is destroyed by ultraviolet light. Widely used products, including bread and cereals, are now enriched with synthetic thiamine, but the addition of high concentrations of sugar increase the need for the vitamin.

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