Whole body numbness that comes and goes can be due to a
mini stroke or transient ischemic attack, compression of spinal up high up in cervical spine, Vit B12 deficiency, anemia, vaso-vagal attack, multiple sclerosis, hypothyroidism, diabetes and panic attack. It can also be a type of seizure.
A comprehensive investigation is required keeping all the points in mind.
Hope this helps. Please let me know if there is any thing else and do keep me posted. Take care!