Xu Lai, chief editor of Guokr, or Nutshell, a popular social networking website for scientists.

Why do we need GM food? Well, take protein for example; the demand for protein is growing, but we don't have an endless supply of soybeans, which are a major source of forage. With regard to protein from animals, the meat, milk and eggs that humans consume require a huge amount of forage to feed all the pigs, chickens and cows.

The protein conversion rate in animals is very low, but chickens have the highest. If a chicken eats 0.9 kg of feed, it can produce 0.5 kg of meat, but a cow needs to consume 5 kg of feed to produce 0.5 kg of meat. As economic conditions have improved, the amount of animal protein in our diet has risen.