Dictionary:

au naturel

  (ō' năch'ə-rĕl', ô' nä-tü-rĕl')

Also from Answers.com... Weight Loss Weight loss options and approaches.

1. 1. Nude.
   2. In a natural state: an au naturel hairstyle.
2. Cooked simply.

[French : au, in the + naturel, natural (state).]

Plain; uncooked, or very simply cooked.

[oh-nah-teur-EHL] The French term for food served in its natural state-not cooked or altered in any way.

adjective

Not wearing any clothes: bare, naked, nude, unclad. Chiefly British starkers. Idioms: in one's birthday suit, in thealtogetherbuffraw, naked as a jaybird, stark naked, without a stitch. See put on/take off, show/hide.