It's the protien powder it self that causes the gas for me, I don't use slpenda in mine, just water,cream, strawberries or blueberries, raw fresh egg, ice cubes. Sure enough, about 10 min after I have a Huge Belch
It does that even if I use nothing but powder and water.

Yes they are o.k. to supplement, but do not use them for a meal replacement, unless it's the specific one for that, most that have 3 carbs or less are not ment to be used that way and it will interrupt this woe/weight loss. You need you full days allotment of real food still.

Good Luck Kathy