I can't find any of the peanut butter you're talking about. Every peanut butter I see at the store (and i'm looking at the natural ones) are 6g of carbs with only 2g of fiber. What brand are you buying?

4g isnt bad.. make sure youre getting natural organic peanut butter, which is generally unsweetned.. youll know bc youll have to mix it when you open the can (store it upside down and let gravity mix it for u!) you likely wont find this stuff in a regular grocery store, unless they have an organic section..