Moderation is key - I am German, and love it over there - especially the food and beer. A bite or two of things, to taste and savor, will not sabotage or ruin your success. And you will most likely be walking alot, since that's what they do over there.
Enjoy your trip (I'm jealous), the breads, the sausages, the cheese, the beer - that's all just a bonus. Make sure to take time out to savor things!