Health Regening Slowly
Solution 1:
If you are somewhere safe, lay down (X on PC) and eat food (no raw or spoiled meat).
If you have the materials, make health potion (HealthSoup if you're going to spawn these in via command line) ahead of time, but check the expiration time before you take them out on an adventure.
Official and vanilla servers as well as most other unofficial servers let you make a recipe when you put a Note in the Cooking Pot (the same cooking pot you can make dye in). Cooked food lasts longer and raises health, stamina, and food (or water if you craft a drink).
The benefit of cooking food is stated directly in one of the tips you might see while loading ARK. I find that food cooked in the pot has a longer spoil time than meat cooked on a fire.
Personal note: I played ARK for a year before getting around to trying the Make Recipe feature, and it made lower-stat and vanilla servers much less dreary to get started on for me.
Experiment and have fun -- be sure to read the stats on the food you make; I once put all my stimberries instead of just the number per serving into the pot before making a recipe and got stuck having to dash down to the water in a dehydrated panic when I had meant to be watching my stats go back up in the stress-free comfort of my keep. :) Good luck!
Solution 2:
Eating food will regen your health faster.