There's getting to be some really silly statements made here on corn/maize due to biofuel interest. Most production in north america is for livestock feed corn, not food.

Many city kids on their first gravel run have stolen and ate field corn cobs that sucked. They were for cows not people. Corn comes in many varieties and hybrids.

I found these stats today:

2005-2006 U.S. Corn Use By Segment (bushels)

Feed/Residual 6.1 billion (54.5%)
Exports 2.1 billion (18.8%)
Ethanol (fuel) 1.6 billion (14.3%)
High Fructose Corn Syrup 530 million (4.7%)
Corn Starch 275 million (2.5%)
Corn Sweeteners 225 million (2.0%)
Cereal/Other 190 million (1.7%)
Beverage Alcohol 135 million (1.2%)
Total 11.2 billion bushels

How is Our Corn Crop Used?
(2005/06 Statistics)

Animal Feed
6.1 billion bushels of corn went to feed animals. Your bacon and egg breakfast, glass of milk at lunch, or hamburger for supper were produced with U.S. corn.

* Livestock in Iowa consumed about 550 million bushels of Iowa’s crop. Of that, about 53% went to hogs, 29% to beef cattle, 12% to poultry and 5% to dairy cattle.

Exports
More than 2.1 billion bushels of corn fed people and animals in other countries.
The 10 biggest customers for U.S. corn are: Japan, Mexico, Taiwan, South Korea, Egypt, Colombia, Algeria, Canada, Israel and the Dominican Republic.

* 750 million bushels from Iowa’s crop left the state. More than 55% went to foreign markets. The rest was used in other parts of the United States.

Corn Sweeteners
755 million bushels were refined into corn sweeteners. Read the labels on beverages and foods to find corn sweeteners in colas, candies, cakes and cookies, lunch meats, jams and jellies, snack foods, salad dressings, and ice cream.

* Processing of all kinds (sweeteners, starches, and ethanol) consumed more of the Iowa crop than any other use – over 870 million bushels.

Ethanol
1.6 billionbushels of corn were fermented into fuel alcohol. Fuel alcohol makes gasoline burn cleaner, reducing air pollution, and it doesn’t pollute the water. Using corn, a renewable resource, to replace gasoline helps reduce our need for petroleum, which can’t be renewed.

* Iowa's growing ethanol industry uses about 450 million bushels alone.

Other Uses
275 million bushels were processed into starch for food and industrial uses: paper, textiles, adhesives, plastics, baked goods, condiments, candies, soups and mixes.

190 million bushels became breakfast cereals, snack chips, tortillas and other corn foods.

135 million bushels of corn were fermented into alcoholic beverages.

Because sweetener, starch and alcohol production doesn't use all of the corn kernel, the 2 billion bushels that went into those products also provided 24.2 million tons of animal feed and 3.3 billion pounds of corn oil.

Source: USDA, industry statistics.
2005-2006 U.S. Corn Use By Segment (bushels)
http://www.iowacorn.org/cornuse/cornuse_3.html

and this:

What can you get from one bushel of corn?

1.6 Pounds of Corn Oil
Cooking Oil, Margarine, Mayonnaise, Salad Dressing, Shortening, Soups, Printing Ink, Soap, Leather Tanning
AND

13.5 Pounds of 21% Protein Gluten Feed
Livestock & Poultry Feed, Pet Food

AND

2.6 Pounds of 60% Gluten Meal
Amino Acids, Fur Cleaner, Poultry Feed
AND 32 Pounds of Starch
Adhesives, Batteries, Cardboard, Crayons, Degradable Plastics, Dyes, Plywood, Paper, Antibiotics, Chewing Gum
OR

33 Pounds of Sweetener
Shoe Polish, Soft Drinks & Juices, Jams and Jellies, Canned Fruit, Cereal, Licorice, Peanut Butter, Pickles, Catsup, Marshmallows
OR

2.7 Gallons of Ethanol/Alcohol
Motor Fuel Additive, Alcoholic Beverages, Industrial Alcohol

http://www.iowacorn.org/cornuse/cornuse_10.html