Synthetic "Vitamin" D supplements are poisoning your body! - "Dietary magnesium effect on swine coronary atherosclerosis induced by hypervitaminosis D." Ito M, et al. Acta Pathol Jpn. 1987.

Abstract
The effects of magnesium (Mg) supplement on coronary arteries of 61 swine, fed various levels of vitamin D3 (VD3), were studied by light and electron microscopy. High frequencies of smooth muscle cell degeneration were observed in groups of swine fed various levels of excess VD3. Swine fed moderately excessive level of VD3 with a basal level of Mg displayed great incidence and magnitude of intimal thickening, while swine fed the same level of VD3 with supplementary Mg sustained only mild intimal thickening. In groups of swine fed high levels of VD3, the prevention of calcification and smooth muscle cell degeneration was observed as a supplementary Mg effect. Plasma analyses indicated that supplementary Mg with excess VD3 increased cholesterol levels but decreased arterial damage. It is concluded that the dietary Mg supplement prevents coronary atherosclerosis induced by hypervitaminosis D.
http://www.ncbi.nlm.nih.gov/m/pubmed/2820185/

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