Depends on what's in it. Some shakes are a complete meal...
The Super Shake recipe
A few people have asked how I use Greens+. As I said, I put a serving in every protein shake I drink, which unless I'm travelling or in a serious hurry is no more than one per day. I call it the Super Shake (creative, no?) because its a true meal replacement. The ingredients are simple:
1 cup water
3 tbsp cottage cheese or yogurt
1 serving Greens+
2 scoops Biotest Low Carb Grow
1/2 cup frozen berries (strawberries, blueberries, raspberries)
3 tbsp ground flax seeds
3 tbsp mixed nuts
Take 3 caps of fish oil with it and you've got yourself a meal on the go. Of course, for more meal ideas, including more shake recipes and some of the best tasting healthy snacks you'll ever taste, check out Gourmet Nutrition.
http://www.johnberardi.com/updates/2005_02_01_.html
Obviously, there are a lot of things you can do to flesh out a shake and make it more than just something to fill your stomach.