Feeding a population of 9 billion in 2050 will require much more food than previously calculated, as people on average become taller and heavier. An average adult in 2014 was 14% heavier, about 1.3% taller and needed 6.1% more energy than in 1975. Human consumption increased by 129% over this time.

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Feeding a population of 9 billion in 2050 will require much more food than previously calculated, as people on average become taller and heavier. An average adult in 2014 was 14% heavier, about 1.3% taller and needed 6.1% more energy than in 1975. Human consumption increased by 129% over this time.