If First World countries and affluent peoples in general were to adopt a less meat-eating diet and embrace vegetarianism, it would profoundly alleviate third world hunger. Much hunger in the world happens because land is devoted to cattle grazing, leading to much food going to cattle feed. That food could instead go to feeding people, for example. In addition, cattle, goat and other animal grazing leads to overuse and ultimately the destruction of good farmland.
Families without food can learn to grow it, even in an urban setting with just a window in an apartment. Vegetarianism can fight global famine because crops can be grown anywhere with the right amount of water and soil. There is nothing to stop charities from sending out seed packs and pots in which to grow lettuce, tomatoes and other vegetables that can become decent stocks within a couple of years.