We have seen that raising beef requires more resources than growing corn. Let’s look at some of the actual numbers.
On farms in the midwestern United States, a hectare of land yields roughly 370 bushels of corn (equivalent to 150 bushels per acre). A bushel consists of 1,250 ears of corn, and each ear typically contains 80 kilocalories. Assume that a person eats only corn and requires 2,000 kilocalories per day. Although this assumption is not very realistic, it allows an approximation of how much land it would take to feed that person.
The person’s food requirement is
2,000 kilocalories⁄day × 365 days⁄year = 730,000 kilocalories⁄year
A hectare of corn produces
370 bushels⁄hectare × 1,250 ears⁄bushel × 80 kilocalories⁄year= 37,000,000 kilocalories⁄hectare
730,000 kilocalories/year ÷ 37,000,000 kilocalories/hectare = 0.02 ha (0.05 acres) of land to feed one person for a year
Thus, one person eating only corn can obtain sufficient calories in a year from 0.02 ha (0.05 acres) of land. What if that person ate only beef? We have seen that it takes 20 kg of grain to produce 1 kg of beef. So it would take 20 times as much land, or 0.4 ha (1 acre), to feed a person who ate only beef.
What happens if we extend this analysis to a global scale? If Earth has about 1.5 billion ha (3.7 billion acres) of land suitable for growing food, is there sufficient land to feed all 6.8 billion inhabitants of the planet if they all eat a diet of only beef?
6.8 billion people × 0.4 ha⁄person = 2,720,000,000 ha
So 2.72 billion ha (6.72 billion acres) would be needed, and the answer is no.
Your Turn How many people eating a beef-