OK - I think I can offer some insight on to this one. My family took our first cruise just this past August out of Philadelphia heading toward Canada. As luck would have it, Hurricane Irene was sitting off the coast around North Carolina. It had enough of an impact that we had pretty choppy Seas the first full day onboard - which was a full-day at sea. Not Good
Anyway, at breakfast that morning my 8 year-old daughter and I were having some difficulty. She ended up leaving the table briefly with my wife because she thought she would be sick.
She didn't - but she also did not want to eat. So I started to take her back to the cabin. The waiter stopped to ask if everything was OK. When I mentioned our issue - he said the Doctor recommended Green Apples. Later that day I was at the Guest Relations desk and they were telling people the same thing.
Long story short - I got my daughter and apple and some dramamine I had carried onboard, and two hours later she was having a blast on the pool deck. So, you decide which you think worked best.
As for me, neither really made my head feel better. The only thing that seemed to help was when we dropped anchor off of Martha's Vineyard the next day. But each day after that, before we set sail again, I would pop a Dramamine and had no further problems. The key with the Dramamine is, you must take it about 1 Hour BEFORE the anticipated motion.
So maybe the Green Apple really did help my daughter.
If nothing else, you can at least say you had a good food choice item on a cruise. When is the last time you heard someone get off a cruise and complain that they ate too many fruits