Epsom salts

I have been on and off this site for 1-2 years. I just read an old flush note because I have printed off alot of things that seemed useful over the past 6-9 months to prepare for a flush. However, I just read a note that said get food grade Epsom Salts that someone said they used that worked better for them than the bathing kind. WHAT!!! They can';t be serious. There is no such difference. Is there? Have I missed this after all this time? Thanks.