vitamin D

noun

1. any of the several fat-soluble, antirachitic vitamins D 1 , D 2 , D 3 , occurring in milk and fish-liver oils, especially cod and halibut, or obtained by irradiating provitamin D with ultraviolet light, essential for the formation of normal bones and teeth.

vitamin D

noun

1. any of the fat-soluble vitamins, including calciferol and cholecalciferol, occurring in fish-liver oils (esp cod-liver oil), milk, butter, and eggs: used in the treatment of rickets and osteomalacia

vitamin D

1. Any of a group of fat-soluble sterols necessary for normal bone growth, especially vitamin D 2 ( ergocalciferol ) and vitamin D 3 ( cholecalciferol ). Vitamin D is found in milk, fish, and eggs and can be produced in the skin on exposure to sunlight. A deficiency of vitamin D in the diet causes rickets in children.

Word History and Origins

Origin of vitamin D¹

First recorded in 1920–25

Example Sentences

Despite its bad reputation, cholesterol is important, as from cholesterol the body produces steroid hormones like cortisol and testosterone or makes vitamin D in the skin.

From Popular-Science

If going from the already-high level of 86 to 100 gives you a benefit, that makes vitamin D sound like a more-is-better performance-booster as opposed to something you just need to get enough of, like food and water.

From Outside Online

For comparison, the current recommended daily allowance of vitamin D is 600 IU for adults, or 4,200 IU per week.

From Outside Online

The case for vitamin D as a sports performance booster got a minor bump from a couple of recent studies.

From Outside Online

There have been a bunch of meta-analyses aggregating the results of vitamin D studies in athletes—but still no consensus.

From Outside Online

I take calcium and vitamin D supplements, but prescription medications are generally only for women in menopause.

From The Daily Beast

The irony in it all is that our bodies need, if not crave, Vitamin D—and more than a chewable tablet.

From The Daily Beast

Spring is starting to arrive, and we plan to soak up as much sun as our vitamin-D-deficient bodies can handle.

From The Daily Beast

Vitamin D3—Most of you reading this are probably vitamin D deficient if you wear clothes and work indoors.

From The Daily Beast

One more thing, take it in the morning otherwise it can disrupt your sleep since vitamin D and melatonin are inversely related.

From The Daily Beast