Not necessarily. Legally, manufacturers are allowed to say "zero" if the count is leass than 1, so the true carb count may well be 0.9. It's also worth checking what they say is the serving size. If the serving size is, say, 1 tablespoon, you are certainly safe enough to have 1 or 2 tablespoons of the dressing, but you can never assume that zero really means zero with manufactured food.

HTH!

Rosebud