We have an abundance of information available to us about calories and nutrition, yet a majority of us still look at our plates (or at the "Nutrition Facts" listed on our food packaging) and have no clue about the amount of calories we're getting with each portion of food that we eat.

As such, I thought this link was cool: What 200 Calories Looks Like

Hopefully, this material will take some of the mystery out of the whole "How much can I eat?" question.

A couple of points worth noting:
1) Calculating calories based on volume of food eaten can be misleading. A heaping plate of vegetables (delivering more nutrient rich food than you can comfortably eat) delivers only 200 calories, while half a candy bar contributes the same. Don't fall into the trap of thinking that eating "just a little bit" of something is consistent with ingesting "just a few" calories. Is it any wonder by looking at these pictures that overeating is so easy to do?

2) Calories are important, nutritional value is more important. Though the above link focuses on calories, food choices should not be made solely based on the amount of calories eaten. You may only drink 200 calories worth of soda, juice or alcohol -- or eat 200 calories of a muffin -- but what building blocks are those food items giving you so that you can build a healthy body? If you view your body as a home, is your home built with an infrastructure of steel, concrete and oak or is it made of aluminum foil, cardboard and balsa wood? Get your calories from high quality sources of food to ensure health and strength of your body.