Global food systems seem to be efficient as they have been meeting up with the demands of the population (I would say both quantitatively and qualitatively). But as is natural with any system there are inefficiencies that crop up. Matters that should be of concern but are accidently ignored until the problem becomes huge enough for human attention and problem resolving. To start off with some of the root problems would be to address the industry based schematics of production which is a whole business of sorts. The whole process is based on non-renewable resources mostly and food processing. This just increases the amount one is feeding and also lessens the labor but along with it effects the environment. Soil Erosion, soil pollution (increased fertilizer use), salinization, effect on water resources (eutrophication) and climate change (greenhouse gases) are some of the physical effects observed in nature. Socially it leads to migration of rural population to urban areas due to loss of employment opportunities leading to overcrowding. Also it raises issues of food safety and health diet that effect human population at a more day to day basis.
What could be the possible solutions? I am still confused about that. In fact I do not know what would be the most efficient. I do not know if we can go back from something that is such huge scale and global to small scale economies. Also residential gardens/backyards for cultivation are again very minute to bring about a huge change. But the ideas of maybe using public policies could be efficient but having seen examples of such zoning, I think the form that gets established are somewhere on the models of an Urban Village. Although urban villages are a great opportunity for farmers getting equal opportunities, the end result is still a distant image from the urban zones of a city and does not necessarily diminish social inequity.