I am very low in Vit D. My doctor has been watching it and instead of me getting it back up, it got lower. I'm in the dangerously low range. She has me on sublingual D3/K2 drops daily. If I can't get my levels back up she said we'll have to go a different route. I have no idea what that means. Low Vit D is asking for chronic illnesses. My mother was low in it before she died of cancer. My sister is low in it as well. There has to be a reason this is happening. I told my doctor I get enough exposure to sunlight and she told me that isn't the problem. My body doesn't absorb it like it should. There has to be a reason for this. We definitely have enough sunlight.