I have friends in their forties and fifties who now say, variously, in tones of voice dripping with superiority, that they:
♦ could not tolerate a seven to eight hour bus ride because to sit for that long would cause them too much pain
♦ could not tolerate a four hour car ride or a twelve hour plane ride for the same reason
♦ have stomachs too delicate to tolerate food in foreign countries
…and more things like that. Is this in any way normal? Why are some of them hinting that I am foolish because I do not have these problems … why would it be desirable to have them? Are these statements actually a form of bragging about luxurious lives at home?
Axé.
coldhearted scientist وداد 
It is just competitive grousing–young people do it too, though about other things. Some people could make it into an olympic sport. And, they are jealous of your travels and perhaps want to point out why they cannot do similarly but without seeminig pathetic (hence the superior tones).
Most USians really do not take care of themselves at all, and so their health deteriorates earlier than one might think. And supposedly some whites do become ill if they eat spicy foods–which I find hard to believe but I should not judge because I have my own foods I have stay a mile away from and no one ever believes that either.
OK, I get it. In this case fear of food is also about fear of food in US restaurants … it is a way of going on about importance of organic slow food, etc. … but in general, I am bad at diagnosing jealousy or envy, it is true!