Your guide to understanding vitamin D – Vitamin D Council Dec 2013

Wonder how I missed seeing this nice 44 page summary for 13 months
It was mentioned in the Vitamin D Council annual report

 Download the PDF in English from Vitamin D Life.

Here is the text extracted from the PDF for those who do not read English.

it is quick extraction - with many error due to the text in the PDF being embedded in graphics

It would take another 4 hours to properly check and format this, but I am the only person working in Vitamin D Life,
and I do not, unfortunately, have the time

What is Vitamin D?

Vitamin D is important for good overall health and strong and healthy bones. It’s also an important factor in making sure your muscles, heart, lungs and brain work well and that your body can fight infection.
Your body can make its own vitamin D when you expose your skin to the sun. You can also get vitamin D from supplements and a very small amount comes from a few foods you eat.
The vitamin D that you make in your skin from sunlight and the vitamin D you get from supplements or food has to be changed by your body a number of times before it can be used. Once it’s ready, your body uses it to manage the amount of calcium in your blood, bones and gut. It’s also used to help cells all over your body to communicate properly.

What does vitamin D do?

Vitamins are chemicals that your body needs for good health. They are vital for everyone and ensure that your body works well, is able to fight illness and heal well.
The link between vitamin D and strong healthy bones was made many years ago. Doctors realized that sunlight, which allows you to produce vitamin D, or taking cod liver oil, which contains vitamin D, helped to pre- is now showing that vitamin D may be important in preventing and treating a number of serious long term health problems.
Vitamin D isn’t like most other vitamins. Your body can make its own vitamin D when you expose your skin to sunlight. But your body can’t make other vitamins. You need to get other vitamins from the foods you eat. For example, you need to get

vitamin d isn’t like most other vitamins. your body can make its own vitamin d when you expose your skin to sunlight
vent a bone condition called rickets in chil- vitamin C from fruits and vegetables. dren. Today, vitamin D is seen as a vital part Also what makes vitamin D unique com-
of good health and it’s important not just for pared to other vitamins, is that when your the health of your bones. Recent research body gets its vitamin D, it turns vitamin D into a hormone. This hormone is sometimes called “activated vitamin D” or “calcitriol.” Getting the right amount of vitamin D doesn’t depend on the foods you eat. To get enough vitamin D you need to expose your skin to sunlight regularly and you may also need to take supplements. This makes getting the right amount a little more complex compared to other vitamins and minerals.

How does vitamin D work?

Vitamin D mainly comes from your skin when it is exposed to sunlight. After that, your body changes the vitamin D so that it can be used.
When your skin is exposed to the sun, it produces vitamin D and sends it to your liver. If you take supplements or eat foods that contain vitamin D, your gut also sends the vitamin D to your liver. From here, your liver changes it to a substance called 25(OH)D. When your doctor talks about your vitamin D levels, he means the amount of 25(OH)D you have in your blood.
This chemical is sent all over your body where different tissues, including your kidney, turn it into activated vitamin D. This activated vitamin D is now ready to perform its duties. From here, it gets a little complicated, but you can think of activated vitamin D working in two ways:
Manages calcium in your blood, bones and gut
As you can see, vitamin D goes a long way from its original form from the skin, supplement or food. But without vitamin D, your body can’t perform at its best.

Are you deficient in vitamin D?

For a number of reasons, many people aren’t getting enough vitamin D to stay healthy. This is called vitamin D deficiency. You may not get enough vitamin D if:

• You don’t get enough sunlight. Your body is usually able to get all the vitamin D it needs if you regularly expose enough bare skin to the sun. However, many people don’t get enough sunlight because they spend a lot of time inside and because they use sunscreen. It’s also difficult for some people to get enough vitamin D from the sun during the winter.
• You don’t take supplements. It’s very difficult to get enough vitamin D from the foods you eat.
• Your body needs more vitamin D than usual, for example if you’re obese or pregnant.

Are certain people more likely to be vitamin D deficient?

There are some groups of people that are more likely to have vitamin D deficiency. The following people are more likely to be lacking in vitamin D:
People with darker skin. The darker your skin the more sun you need to make the same amount of vitamin D as a fair-skinned person. For this reason, if you’re Black, you’re much more likely to have vitamin D deficiency than someone who is White.
People who spend a lot of time indoors during the day. For example, if you’re housebound, work nights or are in a hospital for a long time.
People who cover their skin all of the time. For example, if you wear sunscreen or if your skin is covered with clothes.
People that live far north, like Boston, London or Toronto. This is because there are fewer hours of overhead sunlight the further away you are from the equator.
Older people. They tend to have thinner skin than younger people and this may mean that they can’t produce as much vitamin D.
Infants that are breastfed and aren’t given a vitamin D supplement. If you’re feeding your baby on breast milk alone, and you don’t give your baby a vitamin D supplement or take a supplement yourself, your baby is more likely to be deficient in vitamin D.
Pregnant women.
People who are very overweight (obese).

What are the symptoms of vitamin D deficiency?

The symptoms of vitamin D deficiency are sometimes vague and can include tiredness and general aches and pains. Some people may not have any symptoms at all.
If you have a severe vitamin D deficiency you may have pain in your bones and weakness, which may mean you have difficulty getting around.
You may also have frequent infections. However, not everyone gets these symptoms.
If you think you may have vitamin D deficiency, you should see your physician, or have a blood test to check your vitamin D levels.

How do I know if I’m deficient in vitamin D?

The way doctors measure if you’re deficient in vitamin D is by testing your 25(OH) D level, but most doctors just call this a vitamin D test. Getting this blood test is the only accurate way to know if you’re deficient or not. The level will be presented as a number in units of ng/ml in the United States (in units of nmol/l elsewhere). Here is how different organizations interpret your levels.
25(ohd) guidlines from various organizations

Vitamin D Council
Endocrine
Society
Food and Nutrition Board
Testing
Laboratories

Deficient
0-30 ng/ml
0-20 ng/ml
0-11 ng/ml
0-31 ng/ml

Insufficient
3-39 ng/ml
21-29 ng/ml
12-20 ng/ml

Sufficient
40-80 ng/ml
30-100 ng/ml
>20 ng/ml
32-100 ng/ml

Toxic
>150 ng/ml

Live elsewhere? To convert these into nmol/l, multiply these numbers by 2.5. Now you’re in nmol/l.

How to get the vitamin

The way doctors measure if you’re deficient in vitamin D is by testing your 25(OH) D level, but most doctors just call this a vitamin D test.
Getting this blood test is the only accurate way to know if you’re deficient or not.
The level will be presented as a number in units of ng/ml in the United States (in units of nmol/l elsewhere).
Here is how different organizations interpret your levels.
The two main ways to get vitamin D are by exposing your bare skin to sunlight and by taking vitamin D supplements.
You can’t get the right amount of vitamin D your body needs from food.
the two main ways to get vitamin d are by exposing your bare skin to sunlight and by taking vitamin d supplements. you can’t get the right amount of vitamin d your body needs from food
The most natural way to get vitamin D is by exposing your bare skin to sunlight (ultraviolet B rays).
This can happen very quickly, particularly in the summer.
You don’t need to tan or burn your skin to get vitamin D. You only need to expose your skin for around half the time it takes for your skin to turn pink and begin to burn.
How much vitamin D you produce from sun exposure depends on the time of day, where you live in the world and the color of your skin.
The more skin you expose, the more vitamin D is produced.
You can also get vitamin D by taking supplements. This is a good way to get vitamin D if you can’t get enough sunlight, or if you’re worried about exposing your skin.
Vitamin D3 is the best kind of supplement to take. It comes in a number of different forms, such as tablets and capsules, but it doesn’t matter what form you take, or what time of the day you take it.
Different organizations recommend different amounts of vitamin D supplement to take each day.
The Vitamin D Council recommends taking larger amounts of vitamin D each day than other organizations, because smaller amounts aren’t enough to give you what your body needs.
Most people can take vitamin D supplements with no problems.
However, if you have certain health problems or take certain medicines, you may need to take extra care.
Your body gets most of the vitamins and minerals it needs from the foods that you eat. However, there are only a few foods that naturally contain vitamin D.
Most foods that contain vitamin D only have small amounts, so it’s almost impossible to get what your body needs just from food.
Because there are only small amounts of vitamin D in food there are only two sure ways to get enough vitamin D:

• Exposing your bare skin to sunlight to get ultraviolet B (UVB)
• Taking vitamin D supplements

Exposing your bare skin to sunlight (ultraviolet B )

Your body is designed to get the vitamin D it needs by producing it when your bare skin is exposed to sunlight.
The part of the sun’s rays that is important is ultraviolet B (UVB).
This is the most natural way to get vitamin D.
hours or more for a dark skinned person.
You don’t need to tan or to burn your skin in order to get the vitamin D you need.
Exposing your skin for a short time will make all the vitamin D your body can produce in one day. In fact, your body can produce
human skin can make large amounts of vitamin d when lots of skin is exposed and the sun is high in the sky

Large amounts of vitamin D3 (chole- calciferol) are made in your skin when you expose all of your body to summer sun.
This happens very quickly; around half the time it takes for your skin to turn pink and begin to burn.
This could be just 15 minutes for a very fair skinned person, yet a couple of 10,000 to 25,000 IU of vitamin D in just a little under the time it takes for your skin to turn pink.
You make the most vitamin D when you expose a large area of your skin, such as your back, rather than a small area such as your face or arms.

There are a number of factors that affect how much vitamin D your body produces when your skin is exposed to sunlight.
The amount of vitamin D you get from exposing your bare skin to the sun depends on:

• The time of day- your skin produces more vitamin D if you expose it during the middle of the day
• Where you live- the closer to the equator you live, the easier it is for you to produce vitamin D from sunlight all year round.
• The color of your skin- pale skins make vitamin D more quickly than darker skins
• The amount of skin you expose- the more skin your expose the more vitamin D your body will produce
• the time of year and time of day

When the sun’s rays enter the Earth’s atmosphere at too much of an angle, the atmosphere blocks the UVB part of the rays, so your skin can’t produce vitamin D.
This happens during the early and later parts of the day and during most of the day during the winter season.
The closer to midday you expose your skin, the better this angle and the more vitamin D is produced.
A good rule of thumb is if your shadow is longer than you are tall, you’re not making much vitamin D. In winter, you’ll notice that your shadow is
longer than you for most of the day, while in summer, your shadow is much shorter for a good part of the middle of the day.

where you live

The equator is an imaginary line on the Earth’s surface halfway between the North Pole and South Pole, which divides the Earth into the Northern Hemisphere and Southern Hemisphere.
The further away you are from the equator, the more of an angle the sun will hit the atmosphere at, and the less UVB there will be available for you to produce vitamin D, particularly during the winter time.
In the summer, when the Earth rotates, the angle improves and more UVB reaches the places far away from the equator, allowing you to produce vitamin D outside of winter months.
For example, in the southern United States, in places like Florida, your body can produce vitamin D most of the year, while in more northern places, like New York City or Boston, you can’t produce much vitamin D from November through March. If you

what about the southern hemisphere?

In Buenos Aires, you can’t produce vitamin D in June. In Cape Town, you can’t produce much vitamin D between mid-May and August.
If you live as far south as the bottom tip of Chile and Argentina, you can’t produce vitamin D April through October!
If you’re skin is darker, these windows are even longer by a month or two.
Live in Johannesburg? You can produce vitamin D all year round.
live even further north, like in Edmonton, Canada, you can’t produce vitamin D from October through April.
These times are even longer (by a month or two) if you’re skin type is darker.

your skin type

Melanin is a substance that affects how light or dark your skin color is. The more melanin you have, the darker your skin color.
The amount of melanin you have in your skin affects the amount of vitamin D you can produce.
Melanin protects against skin damage from too much UVB exposure, so darker skins with more melanin allow less UVB to enter the skin.
With less UVB getting through the skin, less vitamin D is produced each minute. This is why if you’re dark skinned, you need more sun exposure to make vitamin D than if you’re fair skinned.
The paler your skin type the more easily your skin can produce vitamin D.
So, if you have skin type I to III, you produce vitamin D more quickly than if you have skin type IV to VI.
For example, if you have skin type I, it might take around 15 minutes of sun exposure to get the vitamin D you need, while if you have skin type V or VI, it might take up to six times longer (even up to 2 hours).
The table below shows the different skin types:
different skin types
Skin Type
Skin color
Skin characteristics

I
White; very fair; red or blond hair; blue eyes; freckles
Always burns, never tans

II
White; fair; red or blond hair; blue, hazel, or green eyes
Usually burns, tans with difficulty

III
Cream white; fair; with any eye or hair color; very common
Sometimes mild burn, gradually tans

IV
Brown; typical Mediterranean Caucasian skin
Rarely burns, tans with ease

V
Dark Brown; mid-eastern skin types
Very rarely burns, tans very easily

VI
Black
Never burns, tans very easily

Because of all these factors - your skin type, where you live and the time of day or season - it can be difficult to work out how much time you need to spend exposing your skin to the sun in order to get the vitamin D you need. A good rule of thumb is to get half the sun exposure it takes for your skin to turn pink to get your vitamin D and expose as much skin as possible.

it can get complicated

Specific recommendations are not easy! Skin types are different and depending on the day of year, place and time of day, recommendations vary.
Let’s see how complicated it can get if we expose a quarter of our body to the sun:

• At noon in Miami, an individual with skin type III would probably need about 6 minutes of exposure to the sun to make 1,000 IU of vitamin D in summer and 15 minutes in winter.
• Someone with skin type V would probably need around 15 minutes in summer and 30 minutes in winter to make 1,000 IU
• At noon in Boston during summer, an individual with skin type III would probably need about 1 hour of sun exposure to make 1,000 IU of D.
• Someone with skin type V would probably need about 2 hours of exposure.
• During the winter months in Boston, it’s not possible for anyone to make vitamin D from the sun, no matter their skin type.

And that’s assuming you’re exposing a quarter of your body.
As you can see, there are lots of things that factor into vitamin D production.
The best recommendation is to get half the sun exposure it takes for your skin to turn pink.

There are other factors which can affect the amount of vitamin D your body

Exposing your skin to UVB and the risk of skin cancer

Exposing your skin to the sun for too long, so that your skin starts to burn can be dangerous.
This is because it can increase your risk of developing skin cancers.
Research to date shows that moderate but frequent sun exposure is healthy but overexposure and intense exposure can increase your risk of skin cancer.
After you have exposed your skin for half the time it takes for you to turn pink, cover up with clothing and go into the shade.
Using sunscreen is not recommended over shade and clothing to protect your skin, because it hasn’t consistently been shown to prevent all types of skin cancers.
But if you do want to use sunscreen, use a sunscreen that blocks both UVA light and UVB light.

protecting the skin

While covering up to prevent too much sun exposure is an important step in protecting yourself from skin cancer, research has not always shown that sunscreen is the safest and most effective method.
Research has shown that sunscreen helps prevent squamous cell carcinoma, but has no effect in preventing basal cell carcinoma.
For melanoma, research has been contradictory.
Some research shows that sunscreen prevents melanoma, while other research shows that it increases your chance of getting melanoma.
For these reasons the Vitamin D Council believes that covering up with clothing and/or going into the shade (after you get a little bit of sun exposure), is a safer way to protect yourself from too much sun exposure.
Infants have delicate skin which burns more easily, so it’s important to use extra care with your baby.
This is why most doctors recommend giving your infant vitamin D supplement and not exposing your baby’s skin to the sun at all.
For older children, the advice is the same as for adults.
You can expose your child’s skin for half the time it takes to burn in order to get the vitamin D they need.
After that, make sure they cover up with clothes, shade and if you wish, sunscreen.
If you have had skin cancer or if you’re worried about exposing your skin to the sun, or that of your child, you can take vitamin D supplements instead.

Vitamin D supplements

how much vitamin d do i need to take?

recommended daily intakes

Vitamin D Council
Endocrine
Society
Food and Nutrition Board

Infants
1,000 IU/day
400-1,000 IU/day
400 IU/day

Children
1,000 IU/day per 25lbs of body weight
600-1,000 IU/day
600 IU/day

Adults
5,000 IU/day
1,500-2,000 IU/day
600 IU/day,
800 IU/day for seniors

can you take more than the recommended amounts?

Yes, you can, but attention and care is needed if you choose to take more supplement than in the recommendations above.
Here are the safe maximums set by the same organizations:

upper limits set by various organizations

Vitamin D Council
Endocrine
Society
Food and Nutrition Board

Infants
2,000 IU/day
2,000 IU/day
1,000-1,500 IU/day

Children
2,000 IU/day per 25lbs of body weight
4,000 IU/day
2,500-3,000 IU/day

Adults
10,000 IU/day
10,000 IU/day
4,000 IU/day

what form of vitamin d should i take and how should i take it?

what if I’m having trouble absorbing vitamin D supplements?
can anyone take vitamin d supplements?
can i get sun exposure and take supplements?
Can I get vitamin my diet?
There are small amounts of vitamin D in a few foods, which makes it nearly impossible to get what you need from food.
However, these foods include:
Fatty fish Beef liver Egg yolks Fortified milk and orange juice Fortified cereals Instant formula
Fatty fish can have 400-1,000 IU per serving. Other foods listed have much smaller quantities, like 100-200 IU per serving.
the vitamin d council believes that trying to get enough vitamin d from your diet is unlikely to give you the vitamin d you need

Testing for vitamin D

How do I get tested?

There are three ways to get tested:

1. ask your doctor for a vitamin d test
   Be specific and ask for a 25(OH)D test. There is another type of blood test for vitamin D, called a 1,25(OH)2D test, but the 25(OH)D test is the only one that will tell you whether you’re getting enough vitamin D. If your health insurance covers a 25(OH)D test, this is a good way to work with your doctor to get tested.
2. order an in-home test
   These tests are sent to your home. You prick your finger and put a drop of blood on to some blotter paper.

You send the paper to a laboratory to be tested. These are an alternative if you don’t want to go to your doctor just for a vitamin D test, or if your insurance doesn’t cover a test.
There are a few companies online that sell these tests.

1. order a test online and get blood work done at a laboratory
   In the United States, there are a few websites that allow you to bypass your doctor and go straight to the testing laboratory.

You can buy a 25(OH)D test from these companies and have the test itself done at your nearest LabCorp.
These tests are a little more expensive than in-home tests.
All three ways of getting tested should give you an accurate result.

What do your results mean?

25(oh)d guidelines from various organizations

Vitamin D Council
Endocrine
Society
Food and Nutrition Board
Testing
Laboratories

Deficient
0-30 ng/ml
0-20 ng/ml
0-11 ng/ml
0-31 ng/ml

Insufficient
31-39 ng/ml
21-29 ng/ml
12-20 ng/ml

Sufficient
40-80 ng/ml
30-100 ng/ml
>20 ng/ml
32-100 ng/ml

Toxic
>150 ng/ml

The Vitamin D Council suggests that a level of 50 ng/ml is the ideal level to aim for.
This is why the Council recommends that adults take 5,000 IU/day of vitamin D supplement in order to reach and stay at this level.
VItamin d council suggests that a level of 50 ng/ml is the ideal level to aim for
The Endocrine Society recommends taking a vitamin D supplement of around 2,000 IU/day to reach and stay above a level of 30 ng/ml.
Lastly, the Food and Nutrition Board recommends 600 IU/day of vitamin D supplement because they believe 20 ng/ml is the ideal level to aim for.

What should you do based on your test results?

If you tested low and want a higher level, you need to get more sun exposure or take a daily supplement with more vitamin D.
If you tested and are right where you want to be, continue your supplement and sun exposure routine.
Keep in mind that your level in the summer is probably higher than in the winter, with more sun and UVB.
So you may need to supplement more in the winter than in the summer to have the same vitamin D level.
If you tested high and want a lower level, you need to take a smaller daily supplement with less vitamin D.
You do not want to have a level over 100 ng/ml, and in fact, anything over 150 ng/ml is considered toxic.
keep in mind that your level in the summer is probably higher than in the winter, with . more sun and uvb. so you may need 0 to supplement more in the winter than in the summer to have the same vitamin d level

Am I getting too much vitamin D?

Although most people take vitamin D supplements without any problems, it’s possible to take too much. This is called vitamin D toxicity. Vitamin D toxicity, where vitamin D can be harmful, usually happens if you take 40,000 IU per day for a couple of months or longer, or take a very large one-time dose.
Vitamin D is fat-soluble, which means your body has a hard time getting rid of it if you take too much. When you take large amounts of vitamin D, your liver produces too much of a chemical called 25(OH)D.
When your 25(OH)D levels are too high, this can cause high levels of calcium to develop in your blood.
High blood calcium is a condition called hypercalcemia.
The symptoms of hypercalcemia include:

• Feeling sick or being sick
• Abdominal pain
• Poor appetite or loss of appetite
• Muscle weakness or pain
• Feeling very thirsty
• Feeling confused
• Passing urine often
• Feeling tired
• Constipation or diarrhea

How do I know if I have taken too much?

A blood test to measure your 25(OH)D levels can tell you whether you have too high of vitamin D levels.
If your 25(OH)D levels are above 150 ng/ml, this is considered potentially toxic and potentially harmful to your health.
You know if your 25(OH)D levels are toxic by a blood test to measure calcium. If calcium is high and 25(OH)D high, then you are getting too much vitamin D.

Very high levels of 25(OH)D can develop if you:
Take more than 10,000 IU/day (but not equal to) everyday for 3 months or more.
However, vitamin D toxicity is more likely to develop if you take 40,000 IU/day everyday for 3 months or more.
Take more than 300,000 IU in a 24 hour period.

If you have taken this much vitamin D, seek medical attention.
Your health care providers will get your calcium and 25(OH) D levels tested.
The current recommended daily allowances for vitamin D set by the Food and Nutrition Board are conservative, so you don’t need to feel worried about toxicity if you take more than their recommended daily allowance.

What should I do if I think I have taken too much vitamin D?

what about children?

The more you weigh, the more vitamin D your body can handle; the less you weigh, the less vitamin D your body can handle.
The cutoffs (listed on page 28) of 300,000 IU in 24 hours or more than 10,000 IU/day for three or more months apply to average adult weight (125-200 lbs).
So, how do you know if your child has gotten too much vitamin D?

• For children that weigh 25 lbs or less, more than 50,000 IU in 24 hours or 2,000 IU/day for over three months is too much and potentially toxic.
• For children that weigh between 25 and 50 lbs, more than 100,000 IU in 24 hours or 4,000 IU/day for over three months is too much and potentially toxic.
• For children that weigh between 50 and 75 lbs, more than 150,000 IU in 24 hours or 6,000 IU/day for over three months is too much and potentially toxic.
• For children that weigh between 75 lbs and 100 lbs, more than 200,000 IU in 24 hours or 8,000 IU/day for over three months is too much and potentially toxic.

If your child has taken too much vitamin D, seek medical attention.

i already tested my 25(OH)d. is my level too high?

If your level is greater than 150 ng/ml, this is considered too high and potentially toxic. Seek medical attention if you have symptoms of hypercalcemia (listed above).
If you do not have symptoms, consider lowering your level.
If your level is not greater than 150 ng/ml, then you are not potentially toxic in vitamin D.

The vitamin D debate

You may have noticed in your reading for almost a hundred years. Before 1997, that recommendations for vitamin D are all over the place.
You might be asking, why does the Food and Nutrition Board recommend 600 IU of vitamin D per day, the Endocrine Society recommend 1,500-2,000 IU of vitamin D per day and the Vitamin D Council recommend 5,000 IU of vitamin D per day?
That’s quite the ' range! What’s safe? What’s too low? Who can I trust?
The reason why recommendations are so different is that right now, there is quite the debate going on in how much vitamin D you need.
This debate probably won’t be resolved for another ten years, until we have a little more research. We’ll explain.
While vitamin D was discovered in the early part of the 20th century, how much you need hasn’t been well understood the recommended daily allowance was set based on what we call “anecdotal evidence,” meaning evidence from small, sometimes personal observations.
When children got rickets, a common treatment was to give cod liver oil, which contains vitamin D.
Most cod liver oil had / 400 IU of vitamin D and since it seemed that cod liver oil both treated and prevented rickets, 400 IU seemed like a good recommendation for children and adults.
In 1997, the Food and Nutrition Board commissioned an organization called the Institute of Medicine to review research on vitamin D and set national recommendations for the United States and Canada.
What they found: we need more research.
So they left the recommendation alone.
Since then, we have seen an explosion in vitamin D research.
Enough new research where there is now a debate on how the research should guide us.
For starters, we now have a very good idea of how much vitamin D humans traditionally got, before we became a more agricultural and urban society.
Scientists looked at the vitamin D levels of hunter gatherers in Africa who were getting year-round full-body sun exposure.
What did they find? They found that these hunter gatherers had average 2 5(OH)D levels of 46 ng/ ml, levels twice that of the average American!
Many organizations (including the Vitamin D Council) believe this tells us how much vitamin D we should be getting.
For whatever reason, the human body was designed to make lots of vitamin D (if given adequate sun exposure), and we say probably for good reason.
To achieve the same vitamin D levels of traditional living hunter-gatherers, it takes most indoor-living adults a supplement of 4,000-5,000 IU/day to achieve the same levels.
That is why you often see recommendations this high, to mimic how much vitamin D humans traditionally got, before we shifted to an indoor society.
However, some public health officials say not so fast.
In medicine, scientists and doctors usually like to see what are called phase III randomized controlled trials before they approve a drug for use.
A phase III randomized controlled trial is a study that involves thousands of people.
The people in these studies either take the drug or take a dummy pill, to see if the drug is better and reasonably safe compared to a dummy pill.
Although vitamin D is no drug, policy makers have decided that we need to put vitamin D to the test, too, before we can start recommending it in larger amounts.
These tests are underway. There are several trials in progress where they are giving thousands of participants either vitamin D or a dummy pill.
They will follow these participants for many years, seeing which ones develop cancers, heart disease and more, to see what the specific benefit of vitamin D is.
Until then, the Food and Nutrition Board says there isn’t enough evidence to publicly recommend higher intakes. In 2010, they set a recommendation of 600 IU/day for adults.
Their reasoning: there is sufficient evidence you need this much for bone health, but there isn’t enough evidence to see if vitamin D helps for a variety of other diseases - diseases like cancers, cardiovascular disease, diabetes, autoimmune disorders and more.
While many organizations disagreed with this recommendation (the Endocrine Society recommends you need at least 1,500-2,000 IU/day for bone health), it looks like public recommendations aren’t going to change anytime soon.
Most trials looking at higher amounts of vitamin D won’t be complete until 2020.
However, some scientists and organiza- * tions - including the Vitamin D Council - say that until research proves that we don’t need as much as hunter gatherers, intakes in the range of 4,000-5,000/
day should be

vitamin d trials underway

Name
Place
Participants
Amount of vitamin D
Outcomes
Year of results

VITAL
USA
20,000
2,000 IU/day
Cancer and heart disease
2017

FIND
Finland
18,000
1,600 IU or 3,200 IU
Cancer, heart disease & diabetes
2020

VIDAL
UK
20,000
60,000 IU/ month
Longevity and others
2020

The trials underway that public health officials are waiting for.

Vitamin D during pregnancy and

breastfeeding
Getting the right nutrients and nutrients that he or she needs to grow eating well when you’re pregnant or and develop, including most vitamins breastfeeding is important for your ba- and minerals. The foods you eat are by’s growth and development. Vitamin important, as the nutrients from these D helps you to develop strong and pass from you to your baby in your healthy bones and it does the same for breast milk. your developing baby.
If you are not getting enough vitamin d yourself, then it’s very important to give your baby a vitamin d supplement
ets. Getting enough vitamin D when a vitamin D supplement. you’re pregnant helps your baby get Please read this section carefully
enough vitamin D too, and also in- so you understand vitamin D nutrition creases your chances of having an during pregnancy and then whether uncomplicated pregnancy. you need to supplement your baby
Breastfeeding helps you to or not with vitamin D, and whether bond with your baby, but it also pro- your breast milk has any vitamin D vides your baby with most food and in it.

How much vitamin D do I need during pregnancy?

recommended daily intake for pregnant women
Vitamin D Council
4,000-6,000 IU/day

Endocrine Society
1,500-2,000 IU/day

Food and Nutrition Board
600 IU/day

How much vitamin D do I need if I breastfeed and how much does my baby need?

SO THE VITAMIN D COUNCIL RECOMMENDS THAT:

• If you take a supplement of 6,000 IU of vitamin D each day you shouldn’t need to give your baby any vitamin D supplement.
  Your breast milk has enough vitamin D for your baby.
• If you aren’t taking a supplement or getting a good amount of sun exposure, or if you’re taking less than 5,000 IU/day of vitamin D,
  you should give your baby a vitamin D supplement.

making sure you, the breastfeeding mother, are getting enough vitamin d

There are two ways to get your vitamin D as a breastfeeding mother; by exposing your bare skin to the sun or by taking supplements.
On days that you get full body sun exposure, you don’t need to take a supplement. However, if you don’t get full body sun exposure on any given day, you need to take 6,000 IU of vitamin D to make sure your breast milk is rich in vitamin D. For most mothers in the 21st century, this means taking a supplement 5-6 days a week.
Be sure not to miss a day of sun exposure or taking your supplement! Breast milk will clear itself of vitamin D very quickly unless you’re regularly getting enough.


Can I take too much vitamin D or can I give my baby too much?

Yes you can. Vitamin D is fat-soluble, which means your body has a hard time getting rid of it if you take too much.
Here are the upper limits set for babies - the safe maximum amounts of daily supplement:
upper limit for daily intake for babies
Vitamin D Council
2,000 IU/day

Endocrine Society
2,000 IU/day

Food and Nutrition Board
1,000-1,5000 IU/day

Here are the upper limits for pregnant or breastfeeding mothers set by the same organizations:
upper limit for daily intake for pregnant women
Vitamin D Council
10,000 IU/day

Endocrine Society
10,000 IU/day

Food and Nutrition Board
4,000 IU/day

Upper limit means the most you can take per day and not expect any problems getting too much.

How much vitamin D is in baby formula?

Depending on the formula milk, there are between 40 and 100 lUs of vitamin D per 100 calories in baby formula. If your baby is 6-months old, depending on how much they weigh, he or she may be getting between 500 to 1,000 calories in a day. What does this come out to? It means a 6-month old baby can be getting anywhere from 200 to 1,000 IU per day, which is quite a range!

It’s best to keep track of how much vitamin D your baby is getting by adding up how much formula he or she has a day and then working out how much vitamin D is in that formula. Based on this result, you can decide if you need to give your baby a vitamin D supplement or not.

Can my baby get vitamin d from the sun?

Exposing your skin to the sun is a great way to get the vitamin D your body needs, providing you’re sensible about how much time you spend in the sun and take care not to burn. However, your baby’s skin is extra-sensitive. For this reason, the American Academy of Pediatrics recommends that babies under six months old should stay out of the sun completely.

References

• American Association for Cancer Research (AACR). Oral vitamin D supplements reduced levels of Ki67 in prostate cancer cells. ScienceDaily, 31 Mar. 2012.
• Cannell JJ, Vieth R, Willett W, Zasloff M, Hathcock J, White JH, Tanumihardjo SA, Larson-Meyer E, Bischoff-Ferrari HA, Lamberg-Allardt CJ, Lappe JM, Norman AW, Zittermann A, Whiting SJ, Grant WB, Hollis BW and Giovannucci E. Cod Liver Oil, Vitamin A Toxicity, Frequent Respiratory, Infections, and the Vitamin D Deficiency Epidemic. Annals of Otology, Rhinology & Laryngology, 2008.
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• Holick MF, Binkley NC, Bischoff-Ferrari HA, Gordon CM, Hanley DA, Heaney RP, Murad MH, Weaver CM; Endocrine Society. Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab, 2011.
• Holick MF. Vitamin D and Health: Evolution, Biologic Functions, and Recommended Dietary Intakes of Vitamin D. In Vitamin D: Physiology, Molecular Biology and Clinical Applications by Holick MF. Humana Press, 2010.
• Hollis BW, Johnson D, Hulsey TC, Ebeling M, Wagner CL. Vitamin D supplementation during pregnancy: double-blind, randomized clinical trial of safety and effectiveness. J Bone Miner Res, 2011.
• Institute of Medicine, Food and Nutrition Board. Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: National Academy Press, 2010.
• Plum LA and Deluca HF. The Functional Metabolism and Molecular Biology of Vitamin D Action. In Vitamin D: Physiology, Molecular Biology and Clinical Applications by Holick MF. Humana Press, 2010.
• Reichrath J and Reichrath S. Hope and challenge: the importance of ultraviolet radiation for cutaneous vitamin D synthesis and skin cancer. Scandinavian Journal of Clinical and Laboratory Investigation, 2012.
• Smolders J, Hupperts R, Barkhof F, Grimaldi LM, Holmoy T, Killestein J, Rieckmann P, Schluep M, Vieth R, Hostalek U, Ghazi-Visser L, Beelke M. Efficacy of vitamin D(3) as add-on therapy in patients with relapsing-remitting multiple sclerosis receiving subcutaneous interferon beta-1a: a Phase II, multicenter, double-blind, randomized, placebo-controlled trial. J Neurol Sci, 2011.
• Tang JY and Epstein Jr, EH. Vitamin D and Skin Cancer. In Vitamin D, Third Edition by Feldman D, Pike JW, and Adams JS. Elsevier Academic Press, 2011.
• Terushkin V, Bender A, Psaty EL, Engelsen O, Wang SQ, Halpern AC Estimated equivalency of vitamin D production from natural sun exposure versus oral vitamin D supplementation across seasons at two US latitudes. J Am Acad Dermatol, 2010.
• Vieth, R. Vitamin D supplementation, 25-hydroxyvitamin D concentrations, and safety. American Journal of Nutrition, 1999.
• Vitamin D, Third Edition by Feldman D, Pike JW, Adams JS. Elsevier Academic Press, 2011.
• Wagner CL, Hulsey TC, Fanning D, Ebeling M, Hollis BW. High-dose vitamin D3 supplementation in a cohort of breastfeeding mothers and their infants: a 6-month follow-up pilot study. Breastfeed Med, 2006.
• Wagner CL, McNeil R, Johnson DD, Ebeling M, Hulsey TC, Hollis BW. Health characteristics and outcomes of NICHD and Thrasher Research Fund (TRF): vitamin D (VITD) supplementation trials during pregnancy. Vitamin D Workshop, presented June, 2012.