Findings ways to perturb the ionome through a healthy status is a tricky part, where fertilizer trials may become handy. It should be noted that the closest healthy point might not be the easiest to reach, and professional agronomist have a lot of flexibility to constrain the model to local conditions and find a better solution than the closest point.
Now I know what your are thinking: "Hey, this might work for humans too!" Indeed, there is no reason why it won't. And I'm working on it.
All computations done for this article can be found in a R Jupyter notebook on GitLab.