Sarah: "...I look ashamed everytime i pass a Pakistani in the street..."
Not to worry, Sarah!
Simply walk over to the Paki, and hand it one of those little gift kits containing one bar of soap, one disposable shaving razor, and a small packet of Kleenex tissues.
If necessary, gesticulate wildly with your arms as if attempting to corral a stray goat, roll your eyes, grimace.
Then, you won't feel guilty!
p.s. - but make sure you have on your running shoes.