There are two forms of vitamin D in the blood: 25-hydroxy vitamin D, or calcidiol, and 1,25-dihydroxy vitamin D, or calcitriol. Tests will measure the amount of 25-hydroxy vitamin D in the blood. This ...

At-home vitamin deficiency tests are available from online retailers, including LetsGetChecked, Everlywell, MyLab Box, and more. Popular test kits can measure a person’s vitamin D, B12, or iron levels ...

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 ...

It’s Wellness Wednesday, and this week’s focus is on vitamin D and its role in overall health. Many people assume they’re getting enough during the summer months, but that’s not always the case. We ...

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