It was mind-blowing for me too! Especially when I realized the connection between eating certain plants and getting rid of my Vitiligo once I stopped eating them. Also I realized that keto and low carb low plant diets might be beneficial exactly because we eliminate all the plant toxins and poisons, although being in ketosis for sure is beneficial too. Also just confirmed to myself once more that eating low protein diet is also essential for health and longevity — thats where most people fail following low carb and ketogenic diets, too much protein is not good, although better than eating lots of grains, given the protein is of good quality.
As for kale and spinach — you can totally overdose on them juicing them. That’s probably the only way, unless you eat them every single day in huge amounts, that is just physically very difficult to do! :)