When eating out my wife and i have a line regarding food hygiene that once crossed cannot be uncrossed so unfortunately over the last 2 months 3 eating places that we frequently use crossed the line which is a hair found in the food. The 3 places were Gerrys on the boulevard, Finbar in Daun and D&C sourdough bakeshop in Valencia.
If that's the case, I think you may run out of places to eat pretty soon. On one occasion while in Cebu, I was having breakfast in a open fronted cafe with family, when my young niece said "look Uncle, there is a mouse" I turned to see the biggest rat I've ever seen, scurry past the table and chairs, just a hair's breadth away! But it's more fun in the Philippines. BTW, Michael Palin is doing a documentary series on Philippines at present, on UK TV, channel 5, Monday's normally at 9pm GMT, or available on You-tube
Thankfully the health risk from ingesting a single human hair is low. Hair is just keratin. Could there be something on it, a bacteria, sure it's possible but unlikely. I'm more concerned with what I can't see. Unwashed hands preparing the food. Vegetables and the like being washed with tap water. Besides, if I drew a line at an occasional hair in my food I wouldn't be able to eat at home either. Cough cough, hairball.
Yes a hair is not really the issue it's as you say above, what we can't see, if they are inattentive enough not to notice a hair in the food they are serving then what else could be in there Anyway not to worry plenty more eating places to choose from.
A hair in your food when eating out in a resstaurant will not improve my appetite. It depends on acceptibility you remove the hair and contineue to eat or send it back to the kitchen. The absolute line for me no longer to visit any restaurant when next morning I have diarrhoea. That's crossing a line I will definitely never return to that place. In the past 20 years it happened a few times. Restaurants in question are still open so maybe other customers never had such an experience or just take it for what it is.