I don't know wether genetically I don't process vitamin D well.
I've tried to learn muscle testing using Brad Nelson´s book The emotion code, but either it is not easy or I don't respond to it.
I'll think of going to a kinesiology specialist.
A few days ago I went to a doctor who made me a blood test (getting a drop from my finger). He saw signals of heavy metals, adrenal fatigue, aminoacids imbalance, excessive oxidation, loss of methyl groups of nuclear DNA, low levels of silica...
He prescribed me Cellfood, VK Vitalfaifa, Bloodroot... among other things.