Vitamin D Vs. D3: Top Differences and Similarities

Often, there is confusion between the two forms of vitamin D, namely vitamin D and vitamin D3. While both are essential for a healthy functioning body, they have their own characteristics: some aspects they share while others they don’t. Here, we will look at the top differences and similarities between these two forms of vitamin D so you can make an informed decision on which one is right for you!

What is Vitamin D?

For many people, the first thing that comes to mind when you hear the word vitamin is “D”. Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and phosphorus. It also works with your parathyroid hormone to make sure that your intestines absorb enough of these minerals.

Vitamin D is produced in the skin when exposed to sunlight, so it's often referred to as "the sunshine vitamin." Even if you live in a place where it's cold most of the year, you can still get your daily dose by eating certain foods (like fatty fish) or taking supplements.

What is vitamin D3?

Vitamin D3 is a form of vitamin D that is produced in the skin, but it also can be found in some foods. This is the most bioavailable form of vitamin D and the one used to treat deficiency.

Vitamin D vs. D3


Vitamin D3 is the more active form of vitamin D, meaning it’s better at doing what it’s supposed to do in your body. It also has a higher bioavailability than other forms of vitamin D. This means that when you take it, more gets absorbed into your bloodstream and works its magic on your body.

Unlike other forms such as vitamin D2 or ergocalciferol (vitamin D2), which are synthesised by plants and fungi respectively, vitamin D3 is made from sunlight exposure or produced by the body itself (more about this below). The only food sources for naturally occurring vitamins would be fatty fish like salmon or tuna fish. 

However, there are many other foods that contain either less vitamins or very small amounts including milk products such as cheese and yogurt. Fortified cereals; orange juice without added calcium lactate along with many others, if consumed regularly over long-term periods, may cause their own health problems due to toxic build-up over time inside our bodies.

Similarities between vitamin D and D3

Vitamin D and D3 are both crucial for your body to function properly, but they have several striking differences. However, there are also many similarities between these two vitamins that should not be overlooked.

  • Both help with bone health: Vitamin D is essential for the body to absorb calcium and phosphorus from food and to build strong bones. It also helps prevent rickets in children who do not receive enough sunlight exposure during infancy or childhood. On the other hand, vitamin D3 is one of the best sources of vitamin D because it's able to increase calcium absorption efficiency in adults by up to 26%.
  • Both can help with muscle health: Vitamin D affects muscle growth through its role in keeping your muscles healthy by regulating calcium levels; this makes you more likely to perform better at sports or exercise without getting tired so easily! Meanwhile, studies show that taking 3-6 mg daily helps reduce the risk of injury while participating in sports activities such as running marathons!

Vitamin D and vitamin D3 are both essential for a healthy functioning body

Despite their similar names, vitamin D and vitamin D3 are two very different supplements. Both are essential for a healthy functioning body and play many roles in the human body.

Vitamin D is a fat-soluble nutrient that’s synthesized in the skin when exposed to sunlight. Once produced, it binds to a protein called DBP (25-hydroxyvitamin D). This molecule helps you absorb calcium from your diet as well as retain it within your bones. It also helps maintain healthy bones and muscles, regulates blood pressure levels and immune function, and supports mental health and development throughout childhood into adulthood.


The bottom line is if you want to supplement with vitamin D, start with a low dose and work your way up. 

If you’re not sure whether you need it or not, or if your doctor recommends it after testing your blood levels, then take a daily vitamin D3 supplement. It’s also important that you eat foods rich in vitamin D3 such as salmon (which contains both D2 and D3).

Disclaimer: The content in this article is solely for informational purposes and is not intended to be medical advice. You should speak with your Physician or other qualified healthcare service provider before use of any medication. Always read and follow the labels.