Close your hand and make a fist. That is approximately the size of your stomach.
Now, take a look at the amount of food you eat at a meal. Could you put all of that food into a container the size of your fist? Probably not.
At yesterday's holiday work lunch, I explained this concept to a couple of co-workers, both of whom admitted to be struggling with their weight. I took out my leftover meal and showed them that the food in that box was actually bigger than the size of my fist. "Yes, but not without the mashed potatoes. That chicken isn't that big."
This woman didn't realize yet that everything that you put in your body is going to be absorbed and either burned as fuel or stored as fat. Since we have sedentary lives/jobs, they will be converted to fat. You can't discount the potatoes - they're going into your body. You have to look at the size of your fist and limit yourself to eating just that much.
The food that is served to us at restaurants is generally 2-3 times larger than the portion of food you should be eating. One restaurant meal can equal all of the calories (or more) than you should eat in an entire day.
Another way to get into the zen of eating is one-bowl eating. I thought of this concept several years ago when I bought a beautiful bowl at a street fair in Palm Springs. The bowl was done by a local artist and its heart-shape fits nicely into your hand. It came with chopsticks and quickly became my "special bowl." With this bowl I know how much food my belly can hold (the whole bowl is slightly bigger than my belly), and eating with chopsticks slows me down. You can see a picture of the bowl in most of my daily pics.
Turns out I'm not the only one who thought of One Bowl eating. There's a book called One Bowl: A Guide to Eating for Body and Spirit by Dan Gerrard. I just started reading it. And while his concept of One Bowl eating is more spiritual and zen like, he also agrees that eating one bowl of food, especially from a significantly important bowl, will help you become more mindful of what you eat and help you lose weight.