I had my vit d3 tested three years ago by a new doctor. My test resultscame back as NONE! Although it is by far one of the most important vitamins to you being healthy, with out it you will be open to many serious illness. NONE of my many doctors had checked it for whatever reason.
I started back then and still am on 10,000 units a day of vit d3. That is 70,000 a week. Im not recomending this for you ar all,just that most people get the wrong test and it sounds up fine. The doctor rechecked me each three months for a year. I feel better,my nails are better. I have more energy, my hair is thicker.
I suggest that everyone ask their primary care doctor to check this along with magnium level once a year.
agnium is what I had extremly low leverls in when all of a sudden I was taken by ambulance to the E.R at hospital. They gave me magnuium as I went into Afib.
I now take what Cleveland heart suggests on a u tube video, that is 400 mg a day to stay healthy for your heart and many other illnesses we get for lack of it. The blood test to chack this is RBC
You have to be careful ,as you need to get GLY-Cinate (might be spelled wrong) The GLY is because this is buffered as magnuium is know to cause loose bowels, cramping and upset stomach. But it has helped me a lot.
Some of this does not relate to your information above but I find it is very common to be low in both. Good Luck