I find that my stomach size/capacity shrinks or expands depending on how much I've been eating in a period of time, and how much exercise ive been doing. When ive been working out heaps and my abdominals are sore, I get full much easier. Also, because im in the "healthy" mindset, i go for protein rich foods like poached eggs, which makes you feel fuller for longer. I really don't like the feeling of being bloated or 100% stuffed. It's uncomfortable. I try to stop before i get to that point, and sometimes I'll bribe myself. For example, ill think: "If I dont eat another bowl of pasta now then I'll have room for dessert in an hour." I understand that breast feeding takes a lot out of you, but im pretty sure quality over quantity makes the difference. So rather than eating double the amount, aim to eat double the nutrients.... make sure your plate if colourful with a variety of fresh vegetables/salads and fresh raw foods. I always feel so much better when I eat unprocessed foods. Refined carbohydrates make me feel sluggish and blah. Also, i think it helps to decide whether you're a grazer or a 3 meals a day person. I know personally i have to eat something every 2-3 hours - without snacks my energy levels slump and i get cranky! But i try to keep the snacks healthy too - carrots with hummos, an apple, an orange, nuts and dried fruit, cheese and grapes. Etc. Another thing ot keep in mind, I think a lot of people mistake hunger for thirst. SOmetimes a cup of tea, some water or a glass of milk can keep you going until your next meal. :)