Scenario (pick one):

* You accidentally travel through time
* Your time machine runs out of fuel or breaks
* Your time machine gets stolen
* A vengeful wizard banishes you to another time/dimension
* You accidentally travel to a parallel Earth
* You intentionally travel to a parallel Earth and get stuck

Let's say you end up stuck in a friendly medieval-tech-level community that is willing to let you stay and help get you on your feet. So even though you'll miss high-tech society, you're going to be able to survive.

However, medieval-level communities don't know much about nutrition, vitamins, minerals, etc, and you'd rather not get [scurvy](https://en.wikipedia.org/wiki/Scurvy) or any other of the nasty diseases caused by nutrient deficiencies. As a bonus, helping your community to become healthier will improve your standing with them, which certainly wouldn't hurt.

How would you go about making sure that you will be getting enough of all of the necessary nutrients?