The reasons vary person to person, but methylation is one reason. There are metabolic pathways that remove these chemicals from your body. Some people have pa

The reasons vary person to person, but methylation is one reason. There are metabolic pathways that remove these chemicals from your body. Some people have pathways that don't work as well as others. MTHFR is one mutation I know of that can cause this. This is kind of an emerging field, so there's no shortage of quackery, but the underlying metabolic pathway seems clear to me.