Diet can refer to several things:

• The nutritional diet of an organism or group. See also: Dietary supplement.
  • Dieting, the deliberate selection of food to control body weight or nutrient intake.
    • Diet as an adjective for foods appropriate for such a diet, e.g. diet cola

• Diet as a formal deliberative assembly. In particular, for some countries, the legislative branch of the country's government is known in English as the Diet. These countries include:
  • Japan - The Diet of Japan, Kokkai (国会).
  • Poland - The Polish parliament, Sejm.

• Dietsch on the subject of linguistics or Dutch history.