Does anyone know what ingredient is used in hibachi cooking (Benihana, etc. ) that can make you "sick"?

Asked by Vavst (7) August 19th, 2009 from iPhone

If I eat at these kinds of restaurants I get the “rumbles” in my stomach within 30 minutes and need to get to a restroom immediately. Once everything Is said and done, all is well. The “sickness” doesn’t linger. The same thing happens when I have lettuce that has been sprayed with that salad bar prrservative.