Vitamin D is completely different than most other vitamins. In fact, it’s a steroid hormone produced from cholesterol when your skin is exposed to the sun. For this reason, vitamin D is often referred ...

What Is Vitamin D Deficiency? A vitamin D deficiency means you don't have enough of this vitamin in your body. You need vitamin D to grow and maintain your bones. You could be at risk for deficiency ...

Certain foods contain more vitamin D. These may include fish, egg yolks, and mushrooms. Modifying your eating can may help reduce or prevent vitamin D deficiency. While supplements and sunshine ...

The sun is one of the best sources of vitamin D for the human body. How much sun a person needs per day depends on factors such as skin type, the season, and cloud coverage. Vitamin D is an essential ...

A D-dimer test checks for certain proteins in the blood to rule out certain clotting disorders. (Photo credit: Science Photo Library/Getty Images) A D-dimer test is a blood test that can be used to ...

Lauren Oster is a contributing writer based in New York City. She covers health and wellness, science and sustainability, lifestyle and culture, and travel. Her work appears in many publications ...

It's that time of year when your body produces less vitamin D. Sunshine is the main source of vitamin D, and we need it to keep our bones and muscles strong. Many people take supplements to meet the ...

You probably already know that vitamin D helps build and maintain strong bones. You may even know that it's produced in your body when the sun’s ultraviolet B (UVB) rays shine on your skin, as the ...

Vitamin D isn’t just about bone health—its other benefits include supporting your immune system, mood, metabolism, and more. Despite its incredible importance, most people still don’t get enough.