It is my general understanding that unless you are severely deficient, Vitamin D supplementation generally takes weeks to bring levels up. It's unlikely that taking it for a few days is going to have any measurable impact on your recovery from illness unless you are severely deficient and/or taking MASSIVE doses, which may or may not be recommended depending on your prior levels and BMI.
It is my general understanding that unless you are severely deficient, Vitamin D supplementation generally takes weeks to bring levels up. It's unlikely that taking it for a few days is going to have any measurable impact on your recovery from illness unless you are severely deficient and/or taking MASSIVE doses, which may or may not be recommended depending on your prior levels and BMI.
See more here: https://www.ccjm.org/content/89/3/154
e: fixed broken URL