Like "re1ndeer: D3 is the supplement needed for heart health. I participate in the Track Your Plaque heart disease reversal program which calls for (among other things) taking enough D3 to maintain a blood level of 60ng/mL. I take 8000iU in the wintertime when I do not get much sunlight and about 6000IU in the summertime to maintain the proper blood level. HH"