Hi Rosemary. I don't know about chelating arteries, but I used to be hypothyroid and so was also on Levothyroxine. I don't like taking drugs and so tried kelp, artichoke extract etc which helped a bit. Then a couple of years ago, I started taking a tablespoon of organic coconut oil daily for another reason altogether. I had been recording my basal body temperature and was amazed to see, after a couple of weeks or so, that it was up from 36.1 to 36.6. Also I noticed I wasn't getting the 4 pm slump and my feet weren't so cold in bed. Coconut oil apparently stimulates the thyroid. The last 3 months I've also been taking between 3 ml to 5ml of Ionic magnesium and my basal temperature has stayed up, even when I didn't take coconut oil. Interestingly, most foods that are quite alkaline seem to have magnesium in them so maybe this is the connection. According to Dr Carolin Dean and others, magnesium is needed for over 300 bodily processes vital for good health. Apparently it affects sex hormones, heart health( hypertension and arrhythmia etc), the thyroid, diabetes, muscle tension and anxiety to mention just a few. I hope you find some helpful remedies .