Blood tests are not reliable, many reasons.
Zinc is a metal ion, cannot 'dissolve' in fluids, very little is needed in blood fluids.
Storage of zinc is more important, Zinc is stored in carbon based molecules:
- proteins
- hormones
- fats / lipids
The amount of zinc is extremely small and not evenly distributed.
Zinc is very important when proteins are being made yet there is no zinc in the finished product.
Testing is invasive and has side effects:
- liver biopsy
- brain biopsy
- kidney biopsy
- muscle biopsy
- cartilage biopsy
- bone marrow biopsy
Zinc is low when you have:
- fatty liver
- cholesterol
- Alzheimer's.
- low hemoglobin.
- hyper- or hypo- thyroid
- autism spectrum disorders
No need to test, go with symptoms, and take zinc-glycinate (never zinc-gluconate)