Milled rice, beriberi

Dramatic changes of immense health importance occur when rice is milled, the most important of which is the loss of much of the thiamin. Fig. R-11 shows the thiamin content of rice at different stages of milling. As noted, highly milled rice is almost devoid of thiamin. This loss has been responsible for much beriberi among people whose diet consists almost entirely of white rice. 

Beriberi is caused by a deficiency of thiamin (also called thiamine, aneurin(e), and vitamin Bj). Classic overt thiamin deficiency causes cardiovascular, cerebral, and peripheral neurological impairment and lactic acidosis. The disease emerged in epidemic proportions at the end of the nineteenth century in Asian and Southeast Asian countries. Its appearance coincided with the introduction of the roller mills that enabled white rice to be produced at a price that poor people could afford. Unfortunately, milled rice is particularly poor in thiamin thus, for people for whom food was almost entirely rice, there was a high risk of deficiency and mortality from beriberi. Outbreaks of acute cardiac beriberi still occur, but usually among people who live under restricted conditions. The major concern today is subclinical deficiencies in patients with trauma or among the elderly. There is also a particular form of clinical beriberi that occurs in patients who abuse alcohol, known as the Wer-nicke-Korsakoff syndrome. Subclinical deficiency may be revealed by reduced blood and urinary thiamin levels, elevated blood pyruvate/lactate concentrations and a-ketoglutarate activity, and decreased erythrocyte transketolase (ETKL) activity. Currently, the in vitro stimulation of ETKL activity by thiamin diphosphate (TDP) is the most useful functional test of thiamin status where an acute deficiency state may have occurred. The stimulation is measured as the TDP effect. 

The peripheral nervous system disease, beriberi, caused by thiamin deficiency, has been known sporadically for nearly 1,300 years it became a major problem of public health in the Far East in the nineteenth century with the introduction of the steam-powered rice mUl, which resulted in more widespread consumption of highly milled (polished) rice. Thiamin was discovered as the factor in the discarded polishings that protected against the disease. 

The severe deficiency of thiamine produces the disease called Beriberi, which affects the brain, heart, and nerves. This disease is prevalent in the Orient because of the abundance of rice they consume. The rice has been milled which strips the rice of thiamine. 

Beriberi associated with the consumption of polished rice diets was once widespread in the East, it still occurs in rural parts of Stmthea.st Asia. The thiamin deficiency arises from an overdependence on polished rice. Polished rice is the result of removal, during milling, of the rice bran which contains thiamin. 

Beriberi, a neurologic and cardiovascular disorder, is caused by adi etary deficiency of thiamine (also called vitamin B,). The disease has been and continues to be a serious health problem in the Far East because rice, the major food, has a rather low content of thiamine. This deficiency is partly ameliorated if the whole rice grain is soaked in water before milling some of the thiamine in the husk then leaches into the rice kernel. The problem is exacerbated if the rice is polished, because only the outer layer contains significant amounts ot thiamine. Beriberi is also occasionally seen in alcoholics who are severely malnourished and thus thiamine deficient. The disease is characterized by neurologic and cardiac symptoms. Damage to the peripheral nervous system is expressed as pain in the limbs, weakness of the musculature, and distorted skin sensation. The heart may be enlarged and the cardiac output inadequate. 

Historically, thiamin deficiency affecting the peripheral nervous system (beriberi) was a major public health problem in South-East Asia following the introduction of the steam-powered mill that made highly polished (thiamin-depleted) rice widely available. There are still sporadic outbreaks of deficiency among people whose diet is rich in carbohydrate and poor in thiamin. More commonly, thiamin deficiency affecting the heart and central nervous system is a problem in people with an excessive consumption of alcohol - to the extent that there was it was seriously suggested in Australia at one time that thiamin should be added to beer. 

Eijkman noted that the disease in birds which resulted from a polished rice diet resembled beriberi in man. He theorized that rice contained too much starch, which poisoned nerve cells, and that the outer layers, removed from the grain in milling, were an antidote. 

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