A vitamin D test measures your blood's vitamin D levels to see if they are too high or too low. Low vitamin D levels can ...

Vitamin D tests certified by the U.S. Centers for Disease Control and Prevention (CDC) Clinical Standardization Programs (CSP) are well calibrated overall, according to a new study presented Sunday at ...

Historically, 400 IU (10 ug) of vitamin D was recommended for better health because it closely approximated the amount of vitamin D in a teaspoonful of cod liver oil. However, 800 to 1,000 IU is the ...

Some vitamin D tests may give misleading results despite progress made in recent years to improve the quality of these assays, according to the US Centers for Disease Control and Prevention (CDC).

There are no official winter health screening tests, but some experts may recommend certain tests for older adults or those ...

A vitamin D deficiency is common, but can be hard to notice. Experts say there are some unexpected symptoms linked to low ...

In a small but revealing study, scientists discovered that tears strongly mirror blood glucose and saliva may reflect vitamin D status. This could lead to less invasive ways to monitor chronic health.

Sometimes it may feel like almost every visit to the doctor includes a dreaded blood draw. Blood tests can reveal a lot about the state of your health. But whether you should get a specific test (and ...

Possible Reasons, and The Best Labs for Fatigue Key Takeaways: Fatigue describes more than just feeling sleepy — it’s a ...

When Mayo Clinic researchers began studying vitamin D’s effects on older adults’ blood pressure, they didn’t anticipate the fascinating results that would emerge. Their discoveries about this common ...