Nutritional deficiencies may appear straightforward initially. Replacing vitamins/minerals will help symptoms (and are certainly recommended to overcome the deficiency). Holistic health is much more than just nutritional replacement. It is about finding out the cause of the deficiency.
Is there a gut problem preventing digestion and absorption, or perhaps we need to assess our motivations behind choosing certain foods? It is also possible we are combining foods that should not be combined together or the body is using much more of a particular vitamin/mineral to overcome a problem somewhere else.