Overfeeding and underfeeding a snake

I know most snakes don't digest very fast. Most of them don't even need to eat every week, and they can be overfed easily.
What are some of the bad things might happen to the snake if it is constantly overfed?


Can snakes be underfed too? Well, I know it is a dumb question, of course they can be starving if without food for a very long time. However, lets say if it is normal for a particular snake species to eat every 14 days. How long can this snake species go without food before it considered as underfed?

Between overfeeding and underfeeding, which one is worse for a snake?