why such a large percentage of Americans are overweight?

Here are the facts: 11.2 million pounds of potato chips; 8.2 million pounds of tortilla chips; 4.3 million pounds of pretzels; 3.8 million pounds of popcorn, and 2.5 million pounds of nuts.

That adds up to 30 million pounds of snacks that Americans will wolf down Super Bowl Sunday, according to research by the Calorie Control Council and the Snack Food Association.

That means the average armchair quarterback will consume 1,200 calories and 50 grams of fat just from snacking — not counting any meals. (Source)