I experienced internal shaking. I could never determine a correlation to any event like eating or anything else. The worse times were when I was pregnant and attended outdoor baseball games, my babies would shake inside of me as if they were terribly cold. I recently had an Electrophoresis and found that I have a Persistence of Fetal Heme. This makes me wonder if having less oxygen in my blood has anything to do with it. I have tried to donate blood on several occassions and was always told at 10.5 heme that I don't have enough to share. I was recently hospitalized and a brilliant doctor checked my magnesium levels. I'm 65 and to my knowlege no one has ever checked my Mg. It was found to be depleted. I was given a shot which felt like stars of energy going throughout my body and felt immediately better! Apparently, it's an iron and is not usually tested for, even though it's next to potassium, salt and calcium on the chart of elements. Perhaps it's essential because ever since having this shot, I have not experienced a tachycardia which I had experienced nightly for years or internal shaking or what I described as "burning blood." Electrophoresis costs $3-$60 and only takes a couple of days. I believe more people should have this to see if they also have heme that is different. Mine has a Gamma Globulin. I have noticed that Mosquitos don't bite me. Maybe they don't like my heme.
I also feel more energized in high elevations. Maybe this heme is good for that.