Japan does have an excellent average life span, right about 80 yrs I believe. The developed countries of the world all have pretty good ranges, mid 70s.

What are the goals of genetically engineered food crops and what are the benefits to world populations?

Crops that are healthier. Crops that yield more product per acre. Crops that are drought and pest resistant.

What do these advances mean? You can produce more food on less acreage. You need less pesticides. You can grow primary food crops in areas where other crops haven't succeeded. You can use less water. You can feed more people.

I think too often arguments against genetic engineering are cloaks for anti-corporation or anti-capitalism arguments. Especially when fear of the "unknown" is one of the mechanisms certain groups attempt to exploit to further their argument.