Reply To: Hello, I have recently learned that I am deficient in vitamin d. (13) I have never been tested before. I am very concerned as I have been having many medical problems for the last 5 years to the point i am currently on disability. Many of my problems are vague and seemingly unrelated. I have to wonder how much and how long this has been affecting me. What is the recommended dosage for vitamin d3 when trying to elevate my levels? And how long does it typically take to get back on track?