I am not sure I understand the Jack in the Box cult-like following, (sort of reminds me of the Chick-Fil-A following) but nonetheless people are very into Jack in the Box so before you go, consider these options.
You should have the:
Asian Chicken Salad, no dressing - It has 140 calories, 1 gram of fat, 470 mg of sodium and 19 grams of carbs. (With the Asian Sesame Dressing add 230 calories, 17 grams of fat, 780 mg of sodium and 20 grams of carbs)
If you don't want a salad, then go for the:
Southwest Chicken Pita, no salsa - It has 230 calories, 3.5 grams of fat, 790 mg of sodium and 34 grams of carbs. (With the Salsa add 5 calories, 105 mg of sodium, 1 gram of carbs)
To find out what not to order
Definitely steer clear of the:
Bacon 'n' Cheese Ciabatta Burger - It has 1120 calories, 76 grams of fat, 1670 mg of sodium and 66 grams of carbs