We'll say that you can take flavorless vitamin pills to prevent you from dying if your favorite food doesn't provide all the nutrients needed to survive.

When you eventually become sick of your current favourite food and it's no longer your favourite food any longer, are you then only allowed to eat your new favourite food from that point on? That should be fine.

@ Bryan: No.

Aw.

meh, ill just eat my 2nd, 3rd, 4th, 5th (etc) favourite food.