I had this from the SDB site today and I think its worth sharing.

Portion Guidelines


While The South Beach Diet(TM) does not aim to limit portion sizes, it can be helpful to keep track of how much you're eating. If you know how much food it takes to satisfy your hunger, you can plan your meals accordingly. And, if you find you're not losing weight, you can determine whether portion size is the culprit.

A great way to get a grasp on portion size is to visualize some everyday objects. Here are a few examples, courtesy of the Mayo Clinic in Rochester, Minnesota.

Three ounces of meat is the size of a deck of cards.
Three ounces of grilled fish is the size of your checkbook.
One ounce of cheese is the size of four dice.
One teaspoon of peanut butter equals the tip of your thumb.
A cup of fruit is the size of a baseball.
A medium apple or orange is the size of a tennis ball.
A medium potato is the size of a computer mouse.
An average bagel is the size of a hockey puck.
To make sure you don't overeat, start with one serving at meals, eat slowly, and go back for seconds only if you are still hungry. Remember, it takes about 20 minutes for your stomach to signal your brain that it's full.