depending on the recipe or the brand, some have olive oil or canola oil - both neutral. some have cumin - a neutral spice.
i never dissected it like this, how interesting that all ingredients are listed as neutral according to dr. d'adamo...
hooray for us hummous-loving blood-typers!
bon appetit!
p.s. i take "neutral" to mean its not going to do anything amazing or terrible. simply a food which does not cause lectin reactions, which in itself is good, according to the research in the book.