This is, of course, a huge answer with many opinions. Sarvation, I feel, is most caused by poverty and a lack of infrastructure. In James Diamond’s book, Guns, Germs, and Steel, he writes about how Europeans conquored the world because they grew food sooner with healthier options – options that Africa, South America, Asia and Native Americans lacked. Few edible and fewer domasticable foods grow in Africa, likely the greatest suffers of starvation. But even if we could bring them enough food, we would have no way to get it to all the people whether because of lack of roads, unstable or non-existant governments, or natural land impediments (rainforests and deserts, for example). The book End of Poverty: Economic Possibilities for Our Time by Jeffrey Sachs has some excellent ideas and solutions on this topic.