Vitamin D dosage recommendations can vary depending on several factors, including your age, skin color, medical history, and where you live.

Vitamin D is commonly known as the “sunshine vitamin.”

That’s because your skin makes vitamin D when it is exposed to sunlight.

Getting enough vitamin D is important for optimal health. It helps maintain strong and healthy bones, aids your immune system, and may help protect against many harmful conditions.

Despite its importance, roughly 41% of people in the United States have a vitamin D insufficiency. Rates of vitamin D deficiency are higher for women, non-Hispanic Black people, and individuals ages 20–29.

There are several other groups of people that have higher vitamin D needs because of their age, where they live, and certain medical conditions.

This article will help you discover how much vitamin D you need daily.

Vitamin D belongs to the family of fat-soluble vitamins, which include vitamins A, D, E, and K. These vitamins are absorbed well with fat and are stored in the liver and fatty tissues.

There are two main forms of vitamin D in the diet:

  • Vitamin D2 (ergocalciferol): found in plant foods like mushrooms
  • Vitamin D3 (cholecalciferol): found in animal foods like salmon, cod, and egg yolks

However, sunlight is the best natural method of obtaining vitamin D3. The ultraviolet (UV) rays from sunlight convert cholesterol in your skin into vitamin D3.

Before your body can use dietary vitamin D, it must be “activated” through a series of steps.

First, the liver converts dietary vitamin D into the storage form of vitamin D. This is the form that is measured in blood tests. Later, the storage form is converted by the kidneys to the active form of vitamin D that’s used by the body.

Though both vitamin D2 and vitamin D3 can increase blood levels of vitamin D, some research suggests that vitamin D3 is more effective.

The main role of vitamin D in the body is to manage blood levels of calcium and phosphorus. These minerals are important for healthy bones.

Research also shows that vitamin D aids your immune system and may reduce your risk of heart disease and certain cancers.

A low blood level of vitamin D is linked to a greater risk of fractures and falls, heart disease, multiple sclerosis, several cancers, and even deathTrusted Source.

In the United States, current guidelines suggest that consuming 400–800Trusted Source International Units (IU), or 10–20 micrograms (mcg), of vitamin D should meet the needs of 97%–98% of all healthy people.

However, many experts believe the guidelines are far too low and point out that there may have been a statistical error in the data originally used to estimate the recommended dietary allowance (RDA).

Your vitamin D needs depend on a variety of factors. These include your age, skin color, current blood vitamin D levels, location, sun exposure, and more.

To reach blood levels linked to better health outcomes, many studies have shown that you need to consume more vitamin D than the guidelines recommend.

For instance, one review of 17 studies found that vitamin D deficiency was associated with a significantly higher risk of developing colorectal cancer.

Another study found that taking people who have obesity have a greater risk of having vitamin D deficiency, so the dose should be adjusted according to size.

What’s more, a recent analysisTrusted Source found that having lower blood levels of vitamin D was associated with an increased risk of heart disease.

Keep in mind that it’s important not to consume more than 4,000 IU of vitamin D without a doctor’s permission, as it exceeds the safe upper limits of intake and is not linked to additional health benefits.

How Much Vitamin D Do You Need and Where Does it Come from?
Watch this video to learn the benefits of vitamin D, plus information about downsides, how much you need, and foods that are rich in vitamin D.
0 seconds of 3 minutes, 19 secondsVolume 0%
Press shift question mark to access a list of keyboard shortcuts
Keyboard Shortcuts
Shortcuts Open/Close/ or ?
Play/PauseSPACE
Increase Volume
Decrease Volume
Seek Forward
Seek Backward
Captions On/Offc
Fullscreen/Exit Fullscreenf
Mute/Unmutem
Decrease Caption Size-
Increase Caption Size+ or =
Seek %0-9
00:00
03:19
03:19
 

A vitamin D deficiency can only be discovered through blood tests that measure levels of storage vitamin D, known as 25(OH)D.

According to the Institute of Medicine (IOM), the following values determine your vitamin D status:

  • Deficient: levels less than 12 nanograms per milliliter (ng/mL), or 30 nanomoles per liter (nmol/L)
  • Insufficient: levels between 12–20 ng/mL (30–50 nmol/L)
  • Sufficient: levels between 20–50 ng/mL (50–125 nmol/L)
  • High: levels greater than 50 ng/mL (125 nmol/L)

However, severalTrusted Source olderTrusted Source studiesTrusted Source have found that a blood level of 30 ng/mL (75 nmol/L) could be even better for preventing fractures, falls, and certain cancers.

Additionally, some other organizations, such as the Endocrine Society, define blood levels of vitamin D lower than 30 ng/mLTrusted Source (75 nmol/L) as a vitamin D deficiency.

Getting plenty of sunlight is the best way to increase your blood vitamin D levels.

That’s because your body makes dietary vitamin D3 out of the cholesterol in the skin when it is exposed to the sun’s UV rays.

However, people who don’t live in sunny countries need to consume more vitamin D through foods and supplements.

Generally speaking, very few foods are great sources of vitamin D. However, the following foods are exceptions:

Mushrooms also produce a significant amount of vitamin D2 when exposed to sunlight or UV light.

In fact, 1 cup (70 g) of raw white mushrooms provides less than 1%Trusted Source of the DV for vitamin D. Meanwhile, the same amount of UV-exposed raw white mushrooms contains nearly 92%Trusted Source of the DV.

If you’re choosing a vitamin D supplement, be sure to find one that contains D3 (cholecalciferol), as it may be more effective at raising your blood levels of vitamin D.

There are certain groups of people who need more dietary vitamin D than others.

These include older people, those with darker skin, people who live far from the equator and those with certain medical conditions.

Older adults

There are many reasons why people need to consume more vitamin D with age.

For starters, your skin gets thinner as you grow older. This makes it harder for your skin to make vitamin D3 when it is exposed to sunlight.

Older people also often spend more time indoors. This means they get less exposure to sunlight, which is the best way to naturally boost vitamin D levels.

Additionally, your bones become more fragile with age. Maintaining adequate blood levels of vitamin D can help preserve bone mass with age and may protect against fractures.

People with darker skin

Research shows that people with darker skin are more prone to vitamin D deficiency.

This is because they have more melanin in their skin — a pigment that helps determine skin color. Melanin helps protect the skin from the sun’s UV rays.

However, it also reduces the body’s ability to make vitamin D3 from the skin, which can make you prone to deficiency.

If you have a vitamin D deficiency, a doctor can recommend an appropriate dosage for supplementation based on your vitamin D blood levels.

Those who live farther away from the equator

Countries close to the equator get plenty of sunlight all year round. Conversely, countries farther away from the equator get less sunlight all year round.

This can cause low blood vitamin D levels, especially during winter months when there is even less sunlight.

For instance, a 2007 studyTrusted Source of Norwegians discovered that they don’t produce much vitamin D3 from their skin during the winter months of October to March.

If you live far from the equator, then you need to get more vitamin D from your diet and supplements. According to one older review, many experts agree that at least 1,000 IU (25 mcg) of vitamin D3 daily is needed in situations where there is no exposure to sunlight.

People with medical conditions that reduce fat absorption

Because vitamin D is fat-soluble, it relies on the gut’s ability to absorb fat from the diet.

Thus, people who have medical conditions that reduce fat absorption are prone to vitamin D deficiencies. These include inflammatory bowel disease (Crohn’s disease and ulcerative colitis), liver disease, and people who have had bariatric surgery.

People with the above conditions are often advised to take vitamin D supplements in an amount prescribed by a doctor.

While it is possible to take too much vitamin D, toxicity is very rare.

In fact, you would need to take extremely high doses of 50,000 IU (1,250 mcg) or more for a long period of time.

It’s also worth noting that it is impossibleTrusted Source to overdose on vitamin D from sunlight.

However, it’s best to consult with a doctor or dietitian for personalized recommendations on how much vitamin D you should take, depending on your needs.

How much vitamin D do we need?

Males and females need the same amount of vitamin D, around 15 mcg (600 IU)Trusted Source daily. However, it can be hard to know how much your body is taking in or creating, as both food and sunlight contribute.

What’s better: Vitamin D2 or D3?

Vitamin D3 appears to be more effective than vitamin D2 at helping the body reach its necessary vitamin D levels. For this reason, if you’re taking supplements, vitamin D3 may be your best choice.

What dose of vitamin D3 supplements do I need?

If you’re taking supplements, how much you need to take will depend on your individual requirements. A doctor can advise you on this.

How much vitamin D is too much?

If you are taking supplements, you should not take more than 50 ng/mLTrusted Source per day. Levels of vitamin D in the blood are too high when they are over 125 nmol / L.

How do I take vitamin D correctly?

First, you will need to discuss your specific needs with a doctor. They will advise on whether or not you need supplements and how much to take. If you are using supplements, always follow the instructions on the package.

Getting enough vitamin D from sunlight and foods is necessary for optimal health.

It helps maintain healthy bones, aids your immune system, and may reduce the risk of many harmful diseases. Yet despite its importance, many people don’t get enough vitamin D.

In addition, older people, people with darker skin, those who live farther away from the equator, and people who can’t absorb fat properly have higher dietary vitamin D needs.

The current recommendations suggest consuming 400–800 IU (10–20 mcg) of vitamin D per day.

However, people who need more vitamin D can safely consume 1,000–4,000 IU (25–100 mcg) daily. Consuming more than this is not advised unless prescribed by a healthcare professional.