I think keeping him away from obvious things like deep fried anything, raw veggies, soda and caffeine would be a good idea. Maybe put him on some sort of multi-vitamin too.
Have you looked into books? "The First Year: IBS" and "Eating for IBS" are both great.
But, like blue mentioned, you may want to consult his doc before you make any drastic diet changes.
Good luck! And please keep us posted.
Co-Moderator for the IBS Forum
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