ユダヤ教で「減量のための食事抜き」は罪ですか？

Judaism's verdict arrives through the health-duty hierarchy — and with a surprising ruling in hand. The baseline: shmirat haguf (guarding the body) makes health-directed eating a religious act, and Maimonides' medical-ethics opening (De'ot 4:1: a healthy body is among 'the ways of God') canonized sensible diet as service. The surprise: the Talmud calls excessive fasting a sin — 'one who accepts upon himself fasts continuously is called a sinner' (applied by extension from the Nazirite discussion, Ta'anit 11a-b) — the tradition rates needless self-denial as seriously as overindulgence. Individual fasts (ta'anit yachid) are permitted with the caveats that they not impair Torah study, work, or health, and halakha exempts the ill and weak from even communal fasts. Applied to dieting: meal-skipping that functions as sensible caloric control is permitted; patterns producing medical harm violate the body-duty; and eating disorders receive the tradition's medical frame — poskim classify anorexia-nervosa situations as pikuach nefesh territory where treatment overrides nearly everything, including, notably, kashrut accommodations in treatment settings (a real and humane modern ruling). The Jewish counselor's line: eat for the body you were lent, and get help when eating itself has become the enemy.