Metals compromise the brain and the immune system. Leaky gut.
Leads to auto-immune disorders.
Some say that all foods except meat can have potential to do so. For those with seriously compromised immune systems/autoimmune, a carnivore diet can heal the gut.
http:// www. paleodiet.com/Voegtlin_1975_The_Stone_Age_Diet.pdf
https:// www. youtube.com/watch?v=eSCMt5F0ldA