Is vitamin D the same as vitamin D3? It’s no secret that maintaining a healthy lifestyle involves exercise, a balanced diet, and getting a daily dose of vitamin D.

Vitamin D is absolutely essential for numerous processes within the body.

It’s associated with keeping bones, teeth, and muscles healthy as it regulates calcium and phosphate levels.

You might have noticed that some vitamin D supplements are labeled as ‘vitamin D2’ whilst others are labeled as ‘vitamin D3.’

This is due to the fact that there are two varieties of vitamin D. These varieties come from different sources, but work in similar ways.

When we talk about vitamin D, we’re usually referring to either vitamin D2 or vitamin D3.

In this quick guide, we’ll be taking a look at both vitamin D and vitamin D3 to investigate their similarities and differences, and ultimately come to a conclusion of whether, or not, they are the same thing.

What Is Vitamin D?

Vitamin D is an umbrella term which covers a family of nutrients that share the same basic chemical structure.

They all have the same number of atoms (carbon, hydrogen, oxygen) but differ in their side chains.

These side chains are responsible for the different biological activities of each vitamin.

For example, vitamin D2 has two hydroxyl groups, while vitamin D3 has three hydroxyl groups.

This difference results in vitamin D3 being more potent than vitamin D2.

As mentioned above, vitamin D2 and D3 come from different sources.

A general rule of thumb is that vitamin D2 is found in plants and fungi, and vitamin D3 is found in animal products such as oily fish.

Vitamin D3 is also created by your skin. When UV rays from the sun hit your skin, these rays interact with a chemical compound known as 7-dehydrocholesterol.

This compound then converts the UV rays into vitamin D3.

This process takes several hours, so you need to spend time outdoors during the summer months to get enough exposure to sunlight.

If you live in an area where the climate doesn’t allow you to go outside for long periods of time, you can supplement your intake of vitamin D through food.

You can also supplement your intake of vitamin D by taking vitamin D supplements that often come in tablet or capsule form.

➡️ When is The Best Time To Take Vitamin D?

Where Can I Get Vitamin D2 and D3 From?

As we’ve covered, the main source of vitamin D3 is derived from sunlight. Vitamin D3 can also be obtained by eating animal-sourced foods.

Vitamin D2, however, can only be obtained from eating plants and fungi (mushrooms for example), and from supplements.

Good Sources Of Vitamin D3

  • Butter/Fat Spreads
  • Eggs (egg yolk in particular)
  • Animal Liver (calf or lamb liver are very rich in Vitamin D3)
  • Oily fish such as mackerel, salmon, and sardines
  • Red meat

Good Sources Of Vitamin D2

  • Fortified foods like most breakfast cereals
  • Dietary supplements
  • Mushrooms and some vegetables

How Much Do I Need To Get Enough Vitamin D?

The recommended dietary allowance (RDA) for vitamin D is 15mcg per day. However, this amount isn’t enough to keep us healthy.

In order to maintain good health, you should aim to consume between 20-30 mcg of vitamin D daily.

That said, if you don’t eat much red meat, you may not require as high a dose of vitamin D.

If you do choose to take a supplement, it’s best to look at the label on the bottle and check how many micrograms of vitamin D are contained within each tablet.

You’ll want to make sure that you’re getting a sufficient amount of vitamin D without taking too much.

As too much vitamin D can be damaging, just as too little vitamin D can.

A study published in the Journal of Clinical Endocrinology & Metabolism showed that people who took 600 mcg of vitamin D had better bone density compared to those who took 300 mcg.

However, even though 600 mcg was considered safe, there were still other factors involved.

It’s important to note that the researchers didn’t find any significant differences in calcium absorption when comparing the two doses.

Five Key Facts About Vitamin D And The Body

1 – It Helps The Body Form Strong Bones

This might come as a surprise, but vitamin D is essential in our body’s production and maintenance of healthy bone matter.

This is because our bodies need vitamin D to absorb calcium from the foods we eat.

So, it is important that your body gets enough vitamin D if you want your bones to remain strong.

2 – It Helps The Body Keep Your Muscles Strong

This applies particularly to elderly people who experience muscle weakness due to atrophy (muscle wasting).

There are a plethora of studies that show that taking vitamin D supplements improves muscle performance and growth.

3 – It Helps The Body Protect Against Gum Disease

Studies conducted by Finnish researchers showed that people with chronic gum disease also had very low levels of vitamin D.

This correlates with a Norwegian study that showed that a lower exposure to sunlight was directly linked with tooth loss.

4 – It Helps Support The Body With Brain Function

There is strong evidence emerging that levels of vitamin D are linked to the development of dementia.

The scientific community is in agreement that larger-scale studies need to be conducted in order to fully investigate this link.

5 – It Might Help The Body With Heart Health

The key word with this one is might – but the evidence from recent studies is compelling.

A recent study conducted to investigate this link concluded that having a vitamin D deficiency is linked to developing heart disease.

Which Is Better At Improving Vitamin D Status?

Whilst both vitamin D2 and D3 are derivatives of the same parent vitamin, Vitamin D3 is much more effective when it comes to raising your vitamin D status.

They’re both similar in the sense that the body absorbs them into the bloodstream, but our livers metabolize them differently.

D3 is converted into 25(OH)D3, which is the form of vitamin D that circulates in the blood.

On the other hand, D2 is converted into 25(OHD2). This is the form of vitamin that gets stored in the fat tissue.

So, whilst D3 is beneficial for improving your vitamin D levels, D2 has its own benefits.

For instance, D2 helps to regulate insulin secretion, and it’s been linked to lower rates of diabetes.

It’s also been shown to help with weight loss, and improve cholesterol levels.

Does The Quality Of The Supplement Affect Their Efficacy?

There is some concern amongst the scientific community that certain D2 supplements are lower quality than most D3 supplements.

As D2 is easier to produce, and is in fact more widely mass-produced, this could lead to quality issues with the supplements.

This lower quality could translate to the supplements being less effective at raising vitamin D status, thus nullifying their effects.

There is some evidence to suggest that D2 supplements are more sensitive to degradation, relevant to how they’re stored.

Too much humidity and changes in temperature have been known to cause them to lose some of their potency.

This is why it’s so important to read the labels carefully before purchasing a supplement.

It’s also worth storing your vitamin D2 supplements in a closed container in a stable environment.

Ultimately, whether this loss of potency directly relates to human health is unknown.

What Are Some Side Effects Associated With Taking Too Much Vitamin D?

There aren’t any immediate side effects associated with consuming too much vitamin D.

However, there have been reports of kidney stones forming due to excessive levels of vitamin D.

There are also concerns about whether vitamin D supplements could increase your risk of cancer.

In fact, according to one study, women who consumed more than 10,000 IU of vitamin D per week had a higher chance of developing breast cancer.

It’s essential to remember that vitamin D is naturally produced by our bodies, but it’s possible to overdose on the nutrient.

It’s always best to speak to your doctor before increasing your intake of vitamin D.

How Can You Tell Whether Your Vitamin D Levels Are Low?

If you think that you might be deficient in vitamin D, then it’s time to get tested.

There are several tests available, including blood testing, urinalysis, and saliva testing.

The most accurate way to test your vitamin D levels is through a blood test.

A simple blood test can tell you if you have adequate levels of vitamin D or if you need to increase your intake.

If you suspect that you’re low on vitamin D, you should talk to your doctor first.

They will be able to advise you on what you should be doing to raise your vitamin D levels.


Vitamin D is an incredibly powerful nutrient for both men and women.

It’s vital for maintaining strong bones, healthy immune systems, and ensuring your body produces enough testosterone.

However, it’s important to remember that not everyone needs to take a vitamin D supplement.

If you don’t live in a region where your exposure to sunlight is limited, then you won’t require extra supplementation.

You should only consider taking a vitamin D supplement if you feel like you may be lacking in nutrients.

Speak to your doctor first to ensure that you know which type of vitamin D supplement would benefit you best.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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