China does need foreign help to feed itself (Nature 474, 7; 2011) when it comes to other factors related to grain production, such as fertilizers.

The country consumes roughly one-third of the world's commercial fertilizers, and this is set to rise by 2–3% annually as its population increases to almost 1.5 billion.

China has been self-sufficient in nitrogen and phosphorus fertilizers since 1997 and 2006, respectively, but still imports about half of its potassium fertilizer. Its clean phosphate rock resource (almost 700 million tonnes) could run out in 30–40 years as demand continues to rise.

Without importing commercial fertilizers, energy and technology to produce grain more efficiently, China will be unable to meet its future grain needs.