the truth is that your body produces a different scent when you eat meat then when you dont . The difference in scent is caused by bacteria
I can testify to having experienced this with different people groups. I have spent some time in asia and there is a popular dish there which is essentialy fermented cabage. It is boiled and then buried (traditionaly) in the ground for a few days until it' s putred (literaly).... and this is eaten every meal of the day! The entire population smelled like this food, and I don' t mean there breath. I mean it came out of their pores (that' s what we used to say anyway).