My Cart



What is the Difference Between Vitamin D and Vitamin D3?

Posted on May 10 2017

When people think of vitamin D in non-sun-form, they're generally thinking about vitamin D3 specifically.

The D vitamin category is broken into two vitamins: vitamin D2 (aka: ergocalciferol) and vitamin D3 (aka: cholecalciferol).

Both vitamin D2 and D3 is needed by the body in order to grow and develop.

Vitamin D2 generally comes from plants or fungus, but can also come from foods such as milks and cereals.

Vitamin D3 is formed when your body synthesizes sunlight after being exposed to ultraviolet rays. It can also be absorbed through the consumption of animal proteins. Vitamin D3 is then broken down by the body into calcitrol, which is very important for fighting cancer.

Should I take a vitamin D3 supplement?

While many people supplement sun exposure and diet by taking a vitamin D supplement, it's not always necessary; some people have adequate levels of vitamin D3 without the use of a supplement, such as those near the equator who also have a lighter skin tone.

In addition to geography and genetics, the following types of lifestyles might find great benefit from a vitamin D3 supplement:

  • vegetarians or vegans
  • people who work indoors
  • people exposed to cold and dark winters
  • people who have regular skin irritations

Because vitamin D3 is needed in healthy quantities by everyone, it is at least a good idea to consider your lifestyle. It may be that your vitamin D3 levels are actually quite good. Alternatively, a D3 supplement might be a great way to balance out your specific lifestyle if any of the items above apply to you.

Brad Glocke is the Co-Founder of Harmonía, a wellness company. He lives with his wife, Kristina, an ACSM certified personal trainer, and his two children in Milwaukee, Wisconsin. He holds a Masters degree from the University of Wisconsin. More information about Harmonía can be found at Brad also hosts a brand new podcast, called the Mind Vitamin Podcast (MVP), which is available on iTunes and Stitcher.



  • Brad: July 23, 2019

    Hi, Bill. Yes – all of these blog posts are written by me. Harmonia is our own name. The reason for the name is 2-fold: 1) I’ve spent some time in latin and South America – for grad school specifically – and so I have an appreciation for the language and culture, and 2) “harmonía” (“harmony”) is what we’re trying to eventually come to promote; the idea that exercise alone won’t “save” you, diet alone won’t either, and neither will supplementation, or reading books… it’s all about the harmony between these different areas of physical and mental development.

  • Bill: July 23, 2019

    Are these posts written by you, your supplier, a generic source? Wondering the source. Also, do you have a single supplier? Is Harmonia your own name, or part of a distribution supply chain? A friend asked me for these details before ordering.

Leave a comment

All blog comments are checked prior to publishing