I once heard that people who spend a bit of time cooking don't eat as much. Is this attributed to the fact that cooks tend to taste as they work? Or does their being bombarded by olfactory input cause a sort of pseudo-satiation.
If the latter is true, does that mean that being around the smell of food could help one fast? Or might it instead be too much of a temptation and conducive to the breaking of the fast?
Depends on how good it smells. One of the best ways to kick an addiction is to go through the process of everything you would do, right up until you eat it. Then walk away. But if you think you'll eat it it might be best not to tempt fate..
Smelling food is part of the cephalic phase of digestion and will prime the body to receive food by initisting gastric acid release. So no it won't help fasting and it is why you probably feel like eating when you smell delicious food.