It was no surprise that without specific ingredient information and portion sizes the people surveyed couldn't accurately guess the content of the foods presented to them. Only the person who prepared the foods would have a fighting chance at guessing those numbers.
Portion size is an important aspect of a healthful diet.
Nutrition professionals and ADA have stressed moderation in portion size, and continually work to educate the public in this area. The Food Guide Pyramid helps consumers know how many servings they need daily and how much of a food counts as a serving. What the public really needs is practical advice for keeping tabs on portion sizes, or referral to the many excellent publications that list the fat and calorie content of popular foods. One-half cup of fruit, vegetables, pasta, or rice is about the size of a small fist. One ounce of cheese is about the size of your thumb.