Not everyone does it, but need a bit of protein powder in my smoothies. If I don’t have it, I find that the sugars in it make me shaky AND I hungry much sooner. I rotate my powders around to keep my metabolism on its toes and to keep from being bored. My big two are both by Naturade, one is 100% Soy and the other is “Soy Free Veg.” The soy has the least taste, but I try not to get too much soy, so I switch it up.
You can get the nutritional info on them here.
Occasionally, I use Nature’s Plus Source of Life:
It’s more supplementy with all manner of vitamins and such in it. It also contains sugar and a “granola” flavor, so I only use it if I’m not expecting to get a lot of good food…or when the base of my smoothie is kinda nasty and I need to mask the flavor. Link to this stuff is here.
Sometimes, when I just don’t have any greens in the house or anything but an apple and a banana, I use this stuff:
It has utterly whack-job Dr. Bronner style packaging, but seems like good stuff and it holds me until lunch, too. Here’s the link.