Over the last year, I have had many people obtain blood tests through their doctor or specialist for vitamin D levels. This test is often not easy to obtain with some doctors refusing outright to order the test, or charging the patient extra to get it done which is outrageous.
What I can tell you is every test result - without exception - has come back as either clinically deficient, or not far off. Nobody, including me, has produced a result anywhere near optimum. If a person is suffering ill health such as depression, low energy, viral infection, heart disease, osteoporosis, diabetes, muscle and joint pain and so on and so on, then nothing less than optimum is acceptable as far as vitamin D is concerned.
Whenever you are addressing a health issue: "Normal" is not necessarily "Healthy". Always find out what is "Optimal" and go for that and settle for nothing less
When interpreting Lab test results for Vitamin D:
Optimal 25-hydroxy vitamin D values are:
45-50 ng/ml or 115-128 nmol/l
Normal 25-hydroxy vitamin D lab values are:
20-56 ng/ml 50-140 nmol/l
Your vitamin D levels should NEVER be below 32 ng/ml, or the equivalent in nmol/l. Any levels below 20 ng/ml are considered serious defiency states and will increase your risk of breast and prostate cancer, osteoporosis and autoimmune diseases like MS and rheumatoid arthritis - to name a few.
(Reference: Holick MF. Calcium and Vitamin D. Diagnostics and Therapeutics. Clin Lab Med. 2000 Sep;20(3):569-90)