I read a book shared with me by a friend who already practiced a whole food plant based vegan lifestyle that helped me tremendously when I first started my vegan journey right after my ER visit. Professor Arnold Ehret's Mucusless Diet Healing System - Annotated, Revised, and Edited by Prof. Spira. It was initially written in the 30s or 40s and this guy brought it more up to date with out current food supply and such.
I thought it was bat shit crazy at first, after having lived the Southern food meat/dairy/egg/sugar/salt/caffeine/"convenient" lifestyle for decades, but practicing what they suggested helped me a lot. Enemas are a part of it, which totally turn some folks off from wanting to read anymore, but I benefited from the knowledge they shared even if I didn't practice it hardcore.
It was the first book I read once I chose to drastically change my habits. I also read the Spira Speaks book that has essays and dialogues from folks who were actively practicing it and receiving one-on-one guidance, and that helped even more. He has a lot of you tube vids, too.
Ever since reading them, I make it a point to eat a salad of some sort with many greens/microgreens/sprouts with the more mucus forming foods to work as sort of an intestinal broom, so to speak. I definitely notice a difference if I don't.