The anabolic effects of eating certain foods can be compared based on how well assimilated they are in your body. Some foods do not assimilate well, so you will need much more to get the same effect. Here’s a breakdown from Dr. Berg.

Eggs 48% efficiency (48% of what you eat is converted to body tissue)
Meat – Fish – Fowl 32%
Egg white 17%
Soy 17%
Diary-Whey 16%
Spirulina 6%