By Ken Worsley -- Self-sufficiency based on a point system? Japan is the world’s largest net importer of food. Nearly 90 percent of wheat consumed in Japan is imported, and about 18 million tons of corn is purchased each year from the United States alone. When global food prices rise—whether due to speculation, unfavorable weather conditions or higher oil prices—Japanese firms and consumers find themselves at the mercy of external forces as price increases pinch budgets.