To a certain degree, yes, to a certain degree, no. Most kids here in the West are not going to understand about people starving, they just won't, but it is not that you can't help them try to understand. You can introduce them to documentary shows, or books that geography people in poor countries. If possible take them on a trip to a poorer country. Thailand is safer than others as a first introduction. Take them to villages, show them people who are poor.
It's not that you can't try to express things to little children, it's simply more difficult to teach them understanding of life when they are young. Some of them will understand.
Teach them how to give. Teaching them how to give makes them understand that other people don't have as much as they do. Then it's easier to tell them that people also don't have enough food. So there are little ways but it also depends on doing it in a gentle way that you don't scare the kid into a depressed state of mind.
It depends on the child themselves, depends on how much you spoil them in other ways. If a child is very spoiled then food is an area where the child will only want, want, want. They scream and they yell when they don't get what they want. It also depends on you being an example for them, to actually show to them that you will eat anything, even if it doesn't taste pleasant. That you won't complain. If you selectively choose, "Oh, this is yummy, yummy, yummy!" in front of the kid and express something like that, well, it doesn't show the kid much balance and equanimity. So if you use your food reflection, then it's easier for you being an example for your children.