Is egg powder an effective egg substitute for protein?

How can you tell when you're full? I am not over-weight, but I tend to over-eat. How can I know when to stop?

Are there other types of eating disorders other than anorexia and bulimia? For example, I have this fear of unnecessary fat in food and eat everything "plain," that is, without butter, oil, dressing, or sauce, etc. I thought that it's good that I'm this health conscious, but my friends say that it's a little obsessive. Is this an eating disorder?

I realize dessert products labeled fat free are high in sugar (which can be converted into fat). But which is the lesser of the two evils: high fat or high sugar content?

I know that plants (besides soy) are considered "incomplete" protein sources, because they don't contain all of the essential amino acids. However, why is it that the nutrition facts of many grains and vegetables say they have protein? For example — a serving of pasta has seven grams of protein, corn has twp grams, and chickpeas have six grams. Is this considered "incomplete" or "complete" protein, and how can you know how much complete protein you are eating when you mix, for example, a serving of corn, and beans? I think average people should eat 50 to 60 grams of protein a day, but how can you ever know how much you are really eating if you are mixing incomplete proteins that together contribute to your day's protein requirement?

I frequently hear that beverages with caffeine or alcohol are not good for replenishing fluids and preventing dehydration. But in reality aren't they just a bit less effective at hydrating your body than other beverages? In other words, if you were stuck in the desert with nothing to drink but beer, coffee and cola, would you actually be worse off and die of thirst sooner if you drank these beverages versus not drinking anything at all?