If you've ever had asthma for any period of time or you get respiratory allergies in spring when the pollen counts in the air are high, then bee pollen or royal jelly (which a couple of BB at my gym swear by) prolly isnt a good idea.
They reckon since they have been taking the royal jelly and bee pollen they have had no colds or flu. That it builds up their resistance somehow. They do take hand fulls of supplements though so who knows.