I have the following symptoms - High Cholesterol, intermittent pain in the knees, low immunity leading to throat infection 3-4 times a year and certainly when in contact with an infected person, a feeling of tiredness by end of the day, even a 40 min walk exhausts me, low sexual libido, if in the event of impact to a bone- the pain lasts for weeks and restless sleep. I find myself in a vicious circle. I was asked by my physician to perform a Vitamin D3 check 25 Hydroxy(OH) Vit D test which yielded a value of 12.4. The Vitamin B-12 levels were observed as 669. Reading on the internet i felt my symptoms are matched with the D3 deficeincy. I would like your advise as well as an advise to whether the condition of bone deterioration ( if any) is reversible. I am a 45 years old male.