Medically reviewed by Soma Mandal, MD A vitamin D test is a blood test that measures the level of vitamin D (calciferol) in ...

Low concentrations of 25-OH vitamin D causes secondary hyperparathyroidism (high levels of parathyroid hormone or PTH). This means a person loses more calcium from his/her bones when PTH is ...

Research shows that vitamin D levels are significantly lower in people with psoriasis when compared with healthy control subjects, but it’s not clear why. Are the low levels the result of having ...

indicated by serum 25(OH)D3 levels, categorizes individuals into deficient, insufficient, or sufficient groups. Vitamin D responsiveness varies among people due to genetic and epigenetic factors ...

Studies have linked low vitamin D with a higher risk of Alzheimer’s disease. However, it’s not clear whether vitamin D supplementation lowers Alzheimer’s risk. You can get vitamin D through ...

Vitamin D supplements might lower blood pressure in seniors who are obese, reducing their heart health risk, a new study says ...

Over the past few decades, the "normal" blood level of vitamin D (25-OH vitamin D) was based on the amount needed to keep PTH from becoming abnormally high. Again, PTH at high levels can cause ...