I recently got my results back from a normal routine blood work, and found out my vitamin d is at 19 ng, and the lower limit is 30 ng. My doctor wants me to take 50,000 iu prescription strength to get it back up.. I have heard fat soluble vitamins are toxic when taken too much.. Is this safe?? I also think it's ergocalciferol and have read that the cholecalciferol absorbs better? Any ideas? Should I just get more sunlight and stay off the supplements? I'm a natural kind of guy and haven't taken a pill in years. I have noticed a slight decrease in energy and oversleeping so I thought this might fix the issue. Any help would be much appreciated! Thanks!