Well marbled steak is a symbol of our modern culture.

The total number of cattle being raised in the whole world is 1.306 billion head. India has the most at 195 million head, followed by Brazil with 156 million head, the U.S. with 103 million head and China with 100 million head each.

Today, well marbled steak is not only a synonym for delicious food, it is at the same time very likely a symbol of modern culture. In Japan 2.86 million head of cattle are kept for their meat, including both beef and dairy cattle. Of these, wagyu (beef cattle) come to 1.74 million head. And 86% of these wagyu are the black wagyu, the main variety. Well marbled beef is produced from these black wagyu.

Consumption of beef in Japan increased seven times in the past forty years.

The United States, which is a major exporter of beef, produces 24% of the world's total. 100 million head of cattle are raised on vast ranches totaling six times the whole area of Japan. Imported beef now comes to 61% of Japan's total beef consumption, which has climbed from 1.2 kg per person per year in 1955 to 8.3 kg per person per year in 1995. The Japanese diet is by now completely westernized.

So now let's compare the amount of feed or energy it takes to keep one head of cattle for twenty months, as between the U.S. and Japan.
Imported meat from the U.S. or other countries which mainly raise cattle methodically on natural grasses on vast ranches uses 550 eu. This is roughly the amount of food that would be eaten by one human being in twenty months.

By contrast, wagyu consume 2650 eu so that five times the amount of energy used in the U.S. is involved. So you see how much labor is put into raising well marbled beef.

One steak represents 28 eu. That equals 28 days worth of food.
One 200 gram well marbled wagyu sirloin steak provides the diner with 0.35 eu (about 700 calories). The energy consumed in order to create this steak is a whopping 28 eu. One steak has used the equivalent of 28 days worth of human food.

Besides beef, yellowtail fish and shrimp raised on farms and hothouse tomatoes and grapes use a great deal of energy to produce the food. We should be very careful how we eat them.

Reference:

Japan Livestock Industry Association http://cali.lin.go.jp/

Kazuhiko Takeuchi and Manabu Tanaka, Seibutsu Shigen no Jizokuteki Riyo. (Iwanami Koza Chikyu Kankyogaku 6) (Continuing Use of Living Resources (Iwanami Lectures, Earth Environment 6)).

Manabu Tanaka, Chikyu kara Mita Norinsuisangyo. (Agriculture, Forestry and Fisheries as Seen from the Earth's Perspective)

World Resources Institute et al, Sekai no Shigen to Kankyo 1998-99. (World Resources 1998-99)