When a crisis hits, things are going to head south quick. In a matter of days your friendly neighbors are now competing with you for the scarce resources in your local area, and once their family's start to starve there's no telling what they will do.
In my opinion it's our duty to ensure we've taken the necessary measures to protect our loved ones no matter what. With riots in the streets, looters on the lookout, and society crumbling to chaos, an investment into body armor could be your ticket to staying alive. To answer the question, I definitely recommend every survivalist invest in body armor.
Just remember. In your local state, you may not legally be able to wear or own body armor. Unless you work in law enforcement or are a member of the military. My advice here would be to move. It's not worth breaking the law over, but in my opinion you want to give yourself the best possible chance to survive, and body armor will help you.
The mistakes preppers make with body armor
Before we get into it though, there's a whole lot of bad information out there when it comes to body armor. I want to clear the air, and ensure we're all on the same page. Unless there has been a complete collapse of society, you will probably never need a full plate set of body armor. It's too impractical. You also run the risk of breaching your own OPSEC when you're wearing what's obviously military-level gear. It may get a neighbor wondering, just what else you have in your stockpile, because it's pretty obvious that someone who has invested in body armor is going to have a whole range of other "goodies" at home.
The best plate body armor
In my opinion you can't get better protection than SAPI plates. SAPI stands for Small Arms Protective Insert. They're ceramic body armor plates used by the United States military, and remain both light and tough as nails. They work by absorbing the impact of the bullet, so the plates will crack if you are hit. This disperses the force of the bullet, allowing you to continue fighting. You will need to replace these once they've taken a round, which is a downside to their steel counterparts, though this is the only one. SAPI plates are light, and you can comfortably wear this body armor all day. What you will need to get it a set of soft armors to wear under the plates. It adds one more layer of protection, and using a Kevlar vest can give you a backup if you are being targeted with armor piercing rounds.
How to actually wear body armor
To wear body armor what you need is known as a plate carry, and it functions exactly as you can imagine. It's a rugged vest that allows you to strap the plates to yourself. My advice is to spend a little more buying a high-quality vest, as you will wear out the cheap ones rather quickly if you're actually using this in the field. Look for a vest that has straps and the ability to add in side plates, so you can give yourself as much protection as possible. The downside is this will get heavy fast, so ensure you're taking the time to practice walking long distances with your armor on, and also test it at the shooting range. The bulk will change your stance slightly when you're shooting, so you need to learn how to adjust.
Do you also need a helmet?
One thing that too many survivalists forget is the importance of a helmet. When the SHTF you've got to remember head protection, because your head is one of the most fragile parts of your body. A blow from a blunt object will take you down. Get a mid-cut ballistic helmet. It's a good balance between protection while staying light weight, and you can always attach additional accessories like flashlights.
What about gloves?
If you're in a combat situation, it's important to protect your hands. The barrel of your gun will get extremely hot, and if you mistakenly grab it you don't want to burn yourself. Find a pair of tactical gloves that aren't too expensive. Like these. You will thank me if you're ever in a real fight for your life. Look for a pair with a protective over your knuckles to guard your hands from any shrapnel or other injuries.
Do I really need everything?
Once you start buying body armor, it becomes an expensive endeavor. I fully believe it's worth every cent you spend, but there are a few items that aren't really worth it. Too much makes you look ridiculous, and you'll also be weighing yourself down with too much gear. Which is critical if you've got a decent trek to your bug out location, any unnecessary weight is going to be a killer. So, forget silly items like knee and elbow pads, or the extended Kevlar protection for your groin and neck. The key is to find the right balance between protection and usability. In addition to the body armor, I'd recommend ensuring you've got adequate eye and ear protection. You just need a pair of cheap earplugs, and put your money into ballistic glasses that will stop any shrapnel getting to your eyes.
Finally, I want to make one last point clear. Body armor is important for preppers, but it is an expensive endeavor. I'd only recommend you purchase this when you've got most of your other preps sorted. It should be one of the last things on your list. In a full collapse of society, you're going to be grateful you invested in body armor. It could just be what keeps you alive.