I don't think the question is settled, but unless you really hate oranges, the cost of adding them to your diet on occasion is negligible, and the reward is eit

I don't think the question is settled, but unless you really hate oranges, the cost of adding them to your diet on occasion is negligible, and the reward is either small (if they don't boost cold resistance) or large (if they do). The payoff matrix is such that I'll eat them anyway. It's probably good for me one way or another, and getting sick or having a sick family member is enough motivation to push me to eat fresh fruit when I'm usually too lazy. Anecdotally, since I started asking for orange juice on flights, I've gotten sick less often after flying. I always used to. But that coincides with other precautions I've started taking, like wearing a face mask.