According to the National Corn Growers Association, about eighty percent of all corn grown in the U.S. is consumed by domestic and overseas livestock, poultry, and fish production

Environmental_effects_of_meat_production [Wikipedia]
Raising animals for human consumption accounts for approximately 40% of the total amount of agricultural output in industrialized countries. Grazing occupies 26% of the earth's ice-free terrestrial surface, and feed crop production uses about one third of all arable land.‏⁶

... cattle require 28 times more land, 11 times more irrigation water, five times more greenhouse gas emissions and six times more nitrogen fertilizer — per calorie consumed — than the four other animal food sources.

While energy use intensities for fruit production vary significantly depending on location and production methods, fruits, on average, have the highest energy index score, primarily because they have low-Calorie densities relative to other foods.

http://link.springer.com/article/10.1007/s10669-015-...