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?
Well, either can be bad, in extremes. I hate to use my standard answer again here, but it depends on the species. Most species of snake are pretty flexible with regards to the amount they need to eat. They can eat allot and fatten up to them go extended periods without food. Or, they can slow themselves down and become less active if food is in short supply.
Overfeeding is mostly a problem if done consistently. Most snakes are not meant to be overweight, and some species deal with it very badly. It stresses their internal systems, organs, & immune system. Basically, it will shorten their life expectancy considerably. Underfeeding is harder to quantify simply. A healthy, adult snake of most species could go months, maybe many months, without food, if all other things are good, (clean water available proper temps & humidity, etc...) with no ill effects. Sometimes hatchlings can go months before their first meal and be fine. You have to watch for signs of problems, weight loss, emaciation, etc...
