How to say "diet" in Japanese

• ダイエットCommon
  noun, suru verb, intransitive verbCovers 'diet' in the weight-loss sense: dieting to lose weight by watching what you eat. Use it for being on a diet; it never means a legislative diet or one's eating habits.
  「太ふとっている人ひとはみんなダイエットすべきだと思おもう」「あなた、私のことを言いってるの」↗

  "I think all fat people should go on a diet". "Are you referring to me"?
• 議会ぎかいJLPT N3approx.Common
  nounCovers 'diet' in the political sense: a legislative assembly, i.e. a parliament or congress. Use it for a national lawmaking body; it has nothing to do with food or eating.
  議会ぎかいはさいごにけんかになった。↗

  The argument ended in a fight.
• 議院ぎいんCommon
  nounShares 議会's political glosses, but really refers to a House or chamber of a legislature rather than the whole institution; for 'diet' in the general sense, 議会 is the word you want.
• 食生活しょくせいかつCommon
  nounCovers 'diet' as eating habits: the overall pattern of what someone eats, as in talk of a healthy diet. It frames food as a long-term pattern of life, not a single meal.
  何なんあんた、またパン？相変あいかわらず変わり映かわりばえのしない食生活しょくせいかつ送おくってんのね。↗

  What, you having bread again? I see you're still leading the same thrilling dietary life as ever.
• 食事しょくじJLPT N4approx.Common
  nounMeans a meal or eating in general; in the 'diet' sense it refers to the food a person eats day to day. It does not by itself imply trying to lose weight.
  彼女かのじょはやせるために食事しょくじを制限せいげんした。↗

  She went on a reducing diet.

Use 「ダイエット」 for weight-loss dieting, 食生活 for eating habits, 食事 for meals and daily food, and 議会 — with 議院 for a legislative chamber — for the political 'diet'.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• ダイエットdiet
• 議会ぎかいcongress
• 議院ぎいんparliament
• 食生活しょくせいかつeating habits
• カロリーオフdiet
• カロリーフリーdiet
• 食事しょくじdiet