Deficiency of vitamin B1 (thiamin) can cause two major deficiency disorders in humans, beriberi and Wernick’s encephalopathy. That is why it is very important to prevent deficiency of thiamin and prevent the deficiency disorders. The prevention of deficiency of thiamin is not difficult, it can be done by educating people about the deficiency disorders and how to prevent them.
Recommended daily allowance of thiamin:
The requirement of thiamin is not fixed like many other vitamins. The requirement of thiamin is based on the number of calorie intake per day and it is approximately 0.5 mg per thousand kilo calorie (Kcal) of food intake per day (if a person is consuming 2000 Kcal per day he/she need 1 mg of thiamin in diet). The body storage of thiamin is approximately 30 mg and if more thiamin is consumed, it is lost in the urine (as thiamin is a water soluble vitamin).
Prevention of thiamin deficiency:
Thiamin deficiency disorders (beriberi and Wernick’s encephalopathy) can be eliminated by educating people (wherever it is prevalent) to take balanced, mixed diet with rich thiamin foods. In rice eating regions rice should be undermilled and preferably parboiled (undermilling and parboiling prevents loss of thiamin from rice). Alcohol consumption should be stopped (reduced). Food rich in thiamin are fresh vegetables, gram, yeast, legumes, pulses etc. and should be consumed in liberal amounts. Read more…
The deficiency of thiamin is not a common problem these days (which was prevalent in many areas of the world only a few decades ago) although it is still prevalent in many developing countries. Due to improved socioeconomic conditions in many parts of the world and diversification of diet has resulted in reduction of thiamin deficiency. But manifestations of minor degrees of thiamin deficiency are still seen in many areas during nutritional surveys, which are calf tenderness, absence of ankle and knee jerks etc. Deficiency of thiamin is seen among chronic alcoholics in Western countries.
Thiamin (vitamin B1) deficiency is more common among rice eating population, where highly polished rice is eaten. The most of the thiamin in rice is present in the outermost layer of rice, which is removed during milling of rice and large portion of the vitamin is also lost during cooking (because thiamin is water soluble vitamin and destroyed during heating).
Thiamin (vitamin B1) deficiency mainly causes two types of deficiency disorders beriberi and Wernick’s encephalopathy. Beriberi mainly occurs in three forms namely dry beriberi, wet beriberi and infantile beriberi.
The manifestations of dry beriberi are mainly of nerve involvement like peripheral neuritis. Nutritional replacement of thiamin can solve the problem of peripheral neuritis. Read more…
Thiamin (vitamin B1) is the first among B complex group of vitamins to be identified and so named as vitamin B1. All the B complex vitamins are water soluble vitamins including thiamin. Thiamin is essential in the metabolism and utilization of carbohydrates. It functions in the decarboxylation of ?-ketoacids, like pyruvate ?-ketoglutarate, and branched chain amino acids and is a source of energy generation. Thiamine pyrophosphate (TPP) acts as a coenzyme of carboxylase enzyme that causes activation of transketolase that mediates the conversion of hexose (like glucose with six carbon) and pentose (five carbon carbohydrates) phosphates. In thiamin deficiency there is accumulation of lactic acid and pyruvic acid in tissues and also in body fluids. Thiamin has also been postulated to play a role in peripheral nerve conduction, although the exact chemical reactions underlying this function are unknown.
Food Sources of Thiamin:
Thiamin is present in many food sources (both plant and animal sources) in nature in abundance. The vegetable or plant food sources of thiamin include whole grain cereals (wheat, maize, rice etc. although milling of rice removes considerable quantity of thiamin and other B complex vitamins from rice and can be commonest cause of thiamin deficiency in predominantly rice eating cultures), gram, yeast, legumes, pulses, nuts and oilseeds (groundnut or peanut), and many different fruits though fruits contains comparatively lesser quantity of thiamin. The animal food sources of thiamin are pork, beef, organ meat, fish, eggs, milk etc. Milk is an important source of thiamin in infants if the mother’s thiamin level in blood is satisfactory. In poor and underdeveloped countries the main source of thiamin is generally the cereal or whole grain (rice, wheat or maize, depending on the dietary habit).
Coffee, both regular and decaffeinated; tea, raw fish, shellfish, contain thiaminases an enzyme which can destroy thiamin and theoretically can cause thiamin deficiency or deplete thiamin stores in heavy tea or coffee drinkers.
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