diet, parliamentary bodies in Japan, Poland, Hungary, Bohemia, the Scandinavian nations, and Germany have been called diets. In German history, the diet originated as a meeting of landholders and burghers, convoked by the ruler to discuss financial problems. The imperial diet or Reichstag of the Holy Roman Empire began as a loose assembly of ecclesiastic princes and imperial cities, meeting at irregular intervals. After 1489 three colleges representing electors, princes, and imperial cities arrived at decisions separately—even over war and peace—then combined them. The emperor could ratify the whole or parts. Among the most important diets were those of Worms (1495) and Cologne (1512); see Maximilian I, Holy Roman emperor. The most important diets of the Reformation were Worms (1521), Speyer (1529), and Augsburg (1530, 1547, 1555). The diet declined in importance and after the peace of Westphalia (1648) it became an assembly of independent princes, meeting after 1663 at Regensburg as a conference of ambassadors without legislative power. For the federal diet of 1815-66, which succeeded the imperial diet, see German Confederation. The term was revived for the legislature of the German Empire in 1871, and was used until the end of World War II; see Reichstag.

The Japanese diet was established as the national legislature in 1889. Until 1947, the upper house (Peers) was appointive, the lower (Representatives) elected. Its powers were negative: no bill could become law without its approval, except in an emergency; the government could function with last year's budget if the current one was not approved; legislation was initiated by the executive. After 1947, the upper house was made elective (Councillors). Suffrage became universal, and the lower house gained precedence over the selection of the prime minister, budgets, and treaties; it can override the upper house on bills with a two-thirds majority. Most legislation is initiated by the cabinet. Since 1947 the Japanese diet, once peripheral, is central to Japan's politics; see Japan, under Government and Politics.

diet, food and drink regularly consumed for nourishment. Nutritionists generally recommend eating a wide variety of foods; however, some groups of people survive on a very limited diet. The traditional Eskimo diet, for example, depended heavily on meat, but Eskimos ate nearly all of the animal; organ meats are rich in vitamins and minerals. Vegetarians exclude meat (and sometimes by extension dairy products) from their diet, often for philosophical reasons. Others exclude only red meat, but eat poultry and dairy products. To maintain a healthy diet, vegetarians need to eat a wide variety of plants whose nutrients complement each other, providing a balance of amino acids and vitamins.

Cultural, Regional, and Practical Factors

Until the advent of refrigeration, the most important factor in a person's diet was availability; diets varied according to animal migrations and the growing seasons of fruits, nuts, and vegetables. Another factor in food selection can be religion. Muslims, for example, are forbidden to drink alcohol.

Diets vary throughout the world. North Africa, with many Muslims, and the Middle East have similar diets. A starchy food (see starch), such as rice, boiled and pounded yam mush, or cassava, is often accompanied by a spicy stew of fish or chicken with vegetables. Other popular dishes include curries, kebabs (marinated meat threaded on a stick and roasted), couscous (steamed wheat semolina), falafel (a spiced fritter), and yogurt. Many Asian diets are based on rice, which is often served with bite-size vegetables and meats accompanied by spicy seasoning. In Europe, bread is often the main starch, but Italy is noted for pasta, a nutritious noodle made from wheat and usually topped with a sauce, such as a small serving of cooked tomatoes garnished with cheese. In Scandinavia, fish in general, and herring in particular, are main staples of the diet.

Food has always been subject to cross-cultural influences, often as a result of colonization and migration of people. Thus, French influences can be seen throughout Asia, particularly in Japan and Indochina; Dutch influences in Indonesia and South Africa; and Indian influences throughout the Commonwealth of Nations. Certain foods, such as dumplings, are found in slightly different forms in all cultures. North American cuisine is an amalgam of Native American foods, such as corn-on-the-cob, and immigrant cuisines, including that of Africans.

Diet in the Twentieth Century

In the 20th cent. diets have been transformed by refrigeration, improved and faster transportation, advances in food preservation, and new farming methods that prolong the growing season and increase the yield per acre. As a result, foods are available more regularly, items purchased in one season can be frozen and consumed in another, and prices have become more competitive. After World War II, increased advertising, particularly on television, and the growing number of households in which all adults are employed, contributed to an increased consumption of unhealthy fast foods. Efforts in the 1980s and 90s by health experts to educate the public about the importance of a healthy diet has had some impact. People are eating more fruits, grains, and vegetables, and less red meat, and are aware of the need to control their weight. The latter has given rise to many ineffective, and sometimes dangerous, fad diets that do not provide all of the necessary daily nutrients. Successful weight control requires a carefully planned regimen of exercise combined with a diet based on the nutrition information supplied by the U.S. Dept. of Agriculture's Food Guide Pyramid (see food pyramid).

Worms, Diet of, 1521, most famous of the imperial diets held at Worms, Germany. It was opened in Jan., 1521, by Holy Roman Emperor Charles V. After disposing of other business, notably the question of the Reichsregiment, the diet took up the question of the recalcitrant behavior of Martin Luther. Charles was induced to summon Luther, who arrived at Worms under a safe-conduct on Apr. 16. At the diet Luther was asked if he would retract his teachings condemned by the pope. After a day's meditation he refused. For a week various theologians argued with him, but he would not retire from his ground. According to tradition Luther ended his defense on Apr. 18 with the words, "Here I stand. I cannot do otherwise. God help me. Amen." Finally, on Apr. 26, the emperor, seeing that the dispute was fruitless, ordered Luther to leave the city. He was formally declared an outlaw in the Edict of Worms (May 25); the lines of the Reformation were thereby hardened.

Regulating food intake to improve physical condition, especially to lose weight. Examples include diets low in fat for weight loss, low in saturated fat and cholesterol to prevent or help treat coronary heart disease, or high in carbohydrates and protein to build muscle. Weight-loss diets are based on reducing calorie intake in different proportions of fat, carbohydrate, or protein; most result in some weight loss, but often the weight is gained back within a few years. Diets must include adequate nutrition and are most effective combined with exercise. Appetite suppressants may have dangerous side effects. Excessive weight loss may be a sign of anorexia nervosa.

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Japanese national legislature. Under the Meiji Constitution, the Diet had two houses, a House of Peers and a House of Representatives, with equal powers. The Diet's role was largely negative: it could block legislation and veto budgets. It was reconstituted under the U.S.-sponsored constitution of 1947. The (upper) House of Councillors seats 247 members, and the (lower) House of Representatives has 480 members. The prime minister, who leads the majority party in the lower house, must be a member. The House of Representatives can override the House of Councillors on most issues.

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