Beef Jerky is a healthy snack at least when eaten in moderation but beef jerky can be unhealthy when consumed too much.
Beef Jerky can cause weight gain as well as potential heart problems when eaten in excess but in moderation such as having a few beef jerky's per day even everyday should pose no health risks.
Beef Jerky is healthier than other foods that are considered Junk Food such as chips and candy but even beef jerky can be unhealthy when eaten in excess.
That goes for other foods as well.
If need be you could live off of just beef jerky and some water if that is all you had to eat.
Having some beef jerky available in a food survival kit in the event of a disaster could help you survive until you can get more food.
Eating just beef jerky the rest of your life though is not healthy as it can be high in fat and raise your cholesterol levels etc.
But eating beef jerky if that is all you had to eat would allow you to survive but it's not best to live off of beef jerky if you have other foods to eat.
You need to eat other fruits, vegetables and many other meats as well.
Beef Jerky is a healthier snack than other snacks but it's not the best healthiest snack available such as apples, oranges, bananas etc.