What Is the Difference Between Vitamin D and Vitamin D3? | Exercise.com Learn: Your Fitness Business Resource

What Is the Difference Between Vitamin D and Vitamin D3?

Tyler Spraul is the director of UX and the head trainer for Exercise.com. He has his Bachelor of Science degree in pre-medicine and is an NSCA-certified strength and conditioning specialist. He is a former All-American soccer player and still coaches soccer today. In his free time, he enjoys reading, learning, and living the dad life. He has been featured in Shape, Healthline, HuffPost, Women's...

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UPDATED: Aug 25, 2020

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  • There is absolutely no difference between vitamin D and vitamin D3.
  • It is vitamin D3 that is absorbed from the sun and aids in the process of calcium being absorbed into the body.
  • Vitamin D is a fat-soluble essential vitamin. It cannot be produced in the body on its own.

There is absolutely no difference between vitamin D and vitamin D3. When the term vitamin D is used, it is meant to describe any D vitamin, D1, D2, or D3.

Vitamin D3 is the vitamin that most people are referring to when they talk about vitamin D.

It is vitamin D3 that is absorbed from the sun and aids in the process of calcium being absorbed into the body.

Vitamin D is a fat-soluble essential vitamin. It cannot be produced in the body on its own. You can get vitamin D through supplements, foods, and, of course, from the sun. It takes about 10 minutes of direct sunlight exposure each day to provide the body with enough vitamin D.

A regular supplement program is only part of a healthy lifestyle. Get more out of your workouts by going PRO today for access to certified personal trainers, workout plans, and more.

What Specifically Is Vitamin D3?

Vitamin D3 is also called cholecalciferol and is not a real vitamin. Vitamin D3 is a secosteroid.

A secosteroid is actually a steroid. The four rings that combine to complete a steroid are broken in a secosteroid, so you don’t get any of the benefits or pitfalls associated with steroids.

While vitamin D3 is stored in the fat of the human body, it is metabolized by the liver. Essentially, when the body needs vitamin D, the liver metabolizes it and ensures it gets where it needs to go.

Truthfully, the body needs vitamin D3 all of the time so the metabolizing action is continual. Vitamin D3 ensures that the body can absorb calcium. Regardless, the body can store up to 60 days worth of vitamin D in the body.

Vitamin D3 is more potent than any of its vitamin counterparts according to the Harvard School of Public Health. It is for this reason that vitamin D3 is typically used for supplementation, although vitamin D3 is sometimes combined with the D2 for a more potent dose.

What Is Vitamin D2?

Vitamin D2, just like D3, is not a vitamin but rather a secosteroid. The scientific name for vitamin D2 is ergocalciferol and it is a synthetic calcium regulator. Vitamin D3 is a natural calcium regulator.

WebMD states that both vitamin D2 and vitamin D3 are the same vitamin. However, vitamin D2 is not absorbed from the sun; it is either taken via supplements or obtained through foods, mainly milk and vegetables.

According to the National Library of Medicine’s Medical Publication website, vitamin D2 and vitamin D3 are not interchangeable. Both have had adequate success for the treatment and prevention of rickets, but that is the extent of its use.

In fact, the articles at the NLM website recommend that nobody should supplement with vitamin D2. This is because it doesn’t provide adequate benefits; vitamin D3 provides everything that vitamin D2 does and more.

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Is It Okay to Take a Supplement That Has Both Vitamins D2 and D3?

Yes, just because vitamin D3 is a more potent version of vitamin D doesn’t mean that vitamin D2 is bad for you. What you do want to think twice about is whether or not you choose a vitamin that only contains vitamin D2. While it won’t hurt you, it is not as potent as vitamin D3.

What Is Better, Taking Vitamin D Supplements or Getting Vitamin D From Natural Sources?

Getting vitamin D naturally is far better for you than taking supplements and it isn’t because supplements don’t work. In the case of vitamin D, it is possible to take too much, which can lead to certain toxicities.

However, when vitamin D is absorbed in the body from through the skin, it is not possible for you to overdose. You see, the skin simply stops absorbing the vitamins when there is enough stored in the body. After that, you are just getting exposure to the sun.

When it comes to supplementation, vitamin D supplements are effective. However, the body doesn’t absorb as many nutrients from the supplement as it does from the sun.

Are There Foods That Contain Vitamin D?

There are certainly plenty of foods that contain vitamin D. Some of the most prolific levels occur in fish. When it comes to grains, you want to look for cereals and breads that are fortified with vitamin D.

Some other foods that contain vitamin D include:

  • Vegetables
  • Fruits
  • Legumes
  • Shellfish
  • Beef liver and kidneys
  • Sausage
  • Fortified milk products

As always, talk to your doctor about your diet and your supplement regimen. You don’t want to increase your dose of vitamin D if it isn’t appropriate and don’t forget that taking supplements of any sort is only one part of an overall healthy lifestyle.

Frequently Asked Questions (FAQ)

Do I have to take vitamin D supplements?

Not unless your doctor has instructed you to take supplements to increase your vitamin D levels.

Are vitamin D supplements safe?

Whether or not vitamin D supplements are safe to take depends on a number of factors. Learn more about the safety of supplements here.

How much vitamin D do I need to take?

No one can answer that aside from your doctor. To learn more about the optimal levels of vitamin D, check out this article.

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