Being sick will obviously be a fear from childhood when you knew no better. Maybe as a young kid you thought you were dying or about to die and recoiled from the experience
Its funny how these early experiences become inground into our psyche
The best answer is not to recoil but to welcome the experience of vomiting so that it isn't a fearful experience for you anymore.
Some young women with eating disorders make themselves sick after each meal not a good thing to do with such frequency but it shows that their fear of gaining weight outweighs their fear of being sick
Pace