Re: Lack of taste and smell..no appetite
I'd agree with the zinc levels.
Pumpkin seeds, pecans, and Brazil nuts are all foods high in it.
Also worth checking if this is any of the medications' side effects. And requesting a similar med without it (the side effects).
Going for lower caloried but very high nutrient levels by much less refined and/or overprocessed foods might help. Though they might be blander tasting, initially.
Loss of appetite itself could be a part of it.
Certain foods are known to enhance digestive powers.
Limiting meals to what can easily be digested could help make the most of the nutrients needed to bring back sense of taste. I believe it's the sense of smell which is much more important in tasting food anyway.