Calcifediol (25-hydroxyvitamin D = 25OHD) raises blood vitamin D (25OHD) within a few hours, rather than the days or week or so it takes vitamin D3 cholecalciferol to raise these levels. 

All people suffering from COVID-19, sepsis, ARDS, Kawasaki disease, MIS etc. urgently need their levels raised and only calcifediol can do this.

Calcifediol is now available, in the USA, Canada and Australia, without prescription, at affordable prices, in quantities needed for emergency vitamin D repletion:  DSM's d.velop and Fortaro

No apologies for the triple headings - this is big news! 

../ To the main page of this site.

Robin Whittle  17 May 2021    Twitter:
(First established 2021-05-02.)


You are reading the best efforts of an electronic technician and computer programmer.   What I write will hopefully help you understand the research, but should not be mistaken for medical advice.  Medical advice is what you get after a doctor has examined you.  Even if I was a doctor, I haven't examined you!

Please read the research carefully and make your own decisions.  If you don't clearly understand it, please consult with someone who does.  Doctors are perfectly capable of understanding all this, but they are very busy, and are generally discouraged from thinking of vitamin D as being important to the immune system.

Jump over  he short version and background sections and go straight to the section describing Rayaldee, Hidroferol, Noediro, Fortaro and d.velop, which is the most accessible form of pharma grade calcifediol in the USA and Canada.  #mb .

Jump straight to the d.velop section, which is followed by my suggestion for how much calcifediol to use per kg bodyweight for this single oral dose emergency vitamin D repletion purpose: #dv .


Short version

COVID-19 patients urgently need their blood vitamin D levels boosted to 50ng/ml (125nmol/L) or more, within hours - not days, weeks or months.  Only calcifediol - the pharmaceutical name for 25-hydroxyvitamin D can do this.  This level is needed for their immune system cells to function properly - to directly combat the virus and to limit self-harming, cytokine storm, overly inflammatory responses which cause severe COVID-19.

For average weight adults (70kg, 154lb) a single oral dose 1.0 milligram calcifediol will do this within 4 hours.   (Actually, half this will do it too - 1mg is to allow for some people absorbing it poorly.)

Ordinary, healthy, vitamin D3 intakes such as 0.125mg (5000 IU) per day (for a 70kg = 154lb adult) will achieve these levels in the long term, but it takes months.

Bolus D3, such as 3.75mg 150,000IU over three days, as recommended by Dr Lindsey Berkson would raise levels over 50ng/ml within several days to a week. 

This is good, but 1 milligram of oral calcifediol will do it in 4 hours and so enable the person, in general, to overcome the infection - and generally to reverse any over-inflammatory responses - much faster.

Calcifediol boosts vitamin D levels fast - hours rather than days (bolus vitamin D3) or months (ordinary 0.125mg 5000 IU / day D3).

Most doctors cannot imagine that vitamin D is so important to the immune system.  They have never heard of vitamin D based autocrine and paracrine signaling, which was first discovered in the mid-2000s and is not widely enough understood.  These needs of the immune system have nothing to do with the one hormonal function of the vitamin D compounds - a very low level of circulating 1,25OHD (calcitriol), produced from circulating 25OHD by the kidneys, which regulates calcium-bone metabolism.

Calcifediol has been very hard to obtain, but since May 2021, it is available, without prescription, as a packet of 60 x 0.02mg tablets = 1.2mg total, for USD$30 including shipping, to customers in the USA and Canada: .

25-hydroxyvitamin D calcifediol now non-prescription and available in Australia, Canada and the USA

Background: Why rapid repletion of circulating 25-hydroxyvitamin D is a crucial step in preventing or reversing the progression of severe COVID-19 etc. and why calcifediol tablets or capsules (or potentially injections or IV drips) are the only way of achieving this

In order to understand the crucial importance of easily available calcifediol, in the current COVID-19 crisis, and for other deadly health conditions, there are a number of things you should read, if you have not already done so. 

Sidebar on using some other nutrients and Ivermectin as well:

Here we concentrate on vitamin D, but in the emergency situations described below in which there is an active viral infection, and/or hyper-inflammatory immune responses, Ivermectin is likely to be highly effective too.  These two interventions - rapid repletion of circulating 25-hydroxyvitamin D with calcifediol and anti-viral anti-inflammatory Ivermectin - operate by completely separate mechanisms, and so should complement each other.  Please see: and

Other nutrients including zinc, magnesium, boron, vitamin C and B vitamins should be considered too.  Omega 3 fatty acids are important for immune system functioning, but would take months to build up in the body.

There is very little vitamin D3 (cholecalciferol) in food.  There is no such thing as a vitamin D rich food.  Unless a person takes supplemental D3, the D3 they need must be supplied by UV-B (short-wavelength ultraviolet) light converting 7-dehydrocholesterol in the skin to D3.   This naturally occurs with high elevation (no more than 45% from the vertical) sunlight, but glass, sunscreen and clothing cut out the UV-B.  There are good reasons to avoid UV-B skin exposure since it damages DNA and so raises the risk of skin cancer.  Melanin-rich skin greatly reduces the amount of incident UV-B which reaches deep enough into the skin.  So people with black or brown skin have generally low vitamin D levels unless they take proper quantities of supplemental D3, such as, for a 70kg person, 0.125mg (5000IU) D3 a day, on average.  This is especially so if they are far from the equator and it is winter, or even in summer if they don't get a lot of direct sun exposure. 

Please see the UK white and BAME vitamin D levels by month graph at: for how low the average levels are in the UK, even for people with low-melanin skin, in summer.   For those with melanin-rich skin, in summer it is much worse, and marginally worse still - to the point of being disastrously low - in winter.   I wrote "40ng/ml" on that chart as being adequate, but this was before I discovered the Quraishi et al. research into hospital acquired infections and wound site infections from the surgery patients in Massachusetts, which shows the real figure is 50 to 55ng/ml, at least for these patients, who were all morbidly obese.   Here is the graph.  The article link and summary is at: .

At least 50ng/ml 125nmol/L blood vitamin D levels are required for all immune system cells to function properly

Here is another graph, in case anyone needs convincing of how important good vitamin D levels are to immune function and so to reducing the chances of severe COVID19.  Links to the articles cited are at .

There is some vitamin D2 is in some mushrooms and fortified milk and other foods.  These are at low levels and D3 is better in every respect.

D3 circulates in the bloodstream and over a period of days to a week or so, newly ingested or UV-B produced D3 is converted by an enzyme there to 25-hydroxyvitamin D.   This is also known as calcifediol and occasionally as "calcidiol".   Hereafter I refer to it as 25OHD in the body, and as calcifediol if it is a pharmaceutical.  These are different names for same molecule.   Every microgram of D3 which enters circulation (the bloodstream) is converted to, very approximately, about 1/3 microgram of 25OHD which goes into circulation.  There is no consensus on the ratio of how many micrograms of D3 are required for the liver to produce a microgram of circulating 25OHD.  3:1 is a reasonable estimate, but values of 2 to 6 might be true, depending on all the circumstances.

Circulating 25OHD has a half-life of a month or so at healthy levels, such as 50ng/ml (125 nmol/L)   This is 50 billionths of a gram of 25OHD per gram of blood.   At higher levels another enzyme, found in many parts of the body, is more active and breaks the 25OHD down in a self-limiting system, so the half-life is shorter.   Almost everyone in the world is not taking good quantities of supplemental D3 and so have levels in the 8 to 22ng/ml range most of the year. At these lower levels circulating 25OHD's half life is, very approximately, two months or so.

Circulating (meaning in the blood, specifically in the liquid part of the blood, rather than the cells - the plasma) 25OHD is what is measured in vitamin D blood tests.

Circulating 25OHD diffuses into the tissues and into cells, through their plasma membrane.  There is no active transporter system.

This 25OHD which diffuses from the blood into cells is required by many types of cells for their autocrine and paracrine signaling systems, where it is consumed, and turned into 1,25OHD inside the cell.

Neither D3 nor 25OHD is a hormone.   A hormone is a substance which is produced in one  location in the body and travels through the bloodstream and by diffusion in the tissues to cells in distant parts of the body.  The level (the chemical concentration, such as in trillionths of a gram per gram of blood) affects those distant cells by controlling some aspects of the cell's behaviour in proportion to the concentration of the hormone molecules.   Hormones are long distance cell-to-cell signaling molecules of endocrine (hormonal) signaling system. 

Circulating 25OHD has two roles.  The first one is known by most people and all doctors.  The second role is hardly known at all.  Most doctors have a vague idea of "vitamin D" affecting immune cells and cells of other types, which is true.  However, very few doctors understand the mechanisms - autocrine and paracrine signaling - since these have mainly been discovered since the mid-2000s.

The first role of circulating 25OHD is to provide the kidneys with a small amount of 25OHD which they convert (in a process controlled by the parathyroid hormone, the level of which is controlled by various aspects of the body's calcium handling system) into 1,25OHD (calcitriol) which goes into circulation.   This circulating 1,25OHD acts as a hormone.  The exact level of circulating, hormonal, 1,25OHD is precisely controlled by the kidneys.  This level is sensed by multiple types of cells in various parts of the body and controls both the absorption of calcium from the intestines into the bloodstream and the actions of osteoblasts, osteoclasts and other cells which are involved in the constant remodeling necessary for bone health.

Unfortunately it is common for even the most experienced vitamin D researchers to state that "vitamin D" (here meaning the three compounds collectively - D3, 25OHD and 1,25OHD) "is a hormone", or "is a secosteriold hormone" which sounds even more impressive.   The vitamin D compounds are extraordinarily important, but the only one of them which acts as a hormone is the very low level of circulating 1,25OHD, as just described.

Sidebar on 1,25OHD:

1,25OHD is the only one of the three compounds which strongly activates vitamin D receptor (VDR) molecules.  When activated (the 1,25OHD binds to the VDR and together they form a bound complex), they alter the patterns of gene expression (copying of gene data in the DNA to messenger RNA) and so the rates at which the cell produces various proteins.  (You may see 1,25OHD referred to as "activated vitamin D".  Vitamin D terminology is confused and confusing.)  The changes to gene expression depend entirely on the cell type.  

In any given cell type, VDR molecules can be "activated" (bind a 1,25OHD molecule, and so change their shape and behavior) when either:
In all cases the bound complexes of 1,25OHD and VDR "migrate" to the nucleus. (I have not found a good description of this.  Perhaps they simply diffuse.  I haven't read of an active transporter system to push them into the nucleus, and as far as I know, the bound complexes don't have a GPS and propellers so they actually move themselves towards and into the nucleus.)

Once in the nucleus, the activated VDRs bind to some other molecules and the resulting complex alters various DNA management arrangements, including how parts of particular chromosomes are unwound from their normally tightly wound (not the spiral structure, see histones) state to expose particular genes to the enzymes which copy their data to new messenger RNA molecules, which go to the cytoplasm and direct ribosomes [WP] to make a particular protein.

So the presence of 1,25OHD-VDR complexes in the nucleus alters the cell's behavior by altering its protein production by altering its transcription of genes.  Exactly which genes are upregulated and downregulated differs from one cell type to the next.

This circulating, hormonal, 1,25OHD is at a very low level: such as 1000  times less concentrated than the (ideally) 50 parts per billion of 25OHD.  Its half-life is a day or less.  The kidneys can maintain the required level pretty well with circulating 25OHD levels of 20ng/ml or so - though, unfortunately, many people don't even have this.  Some people have 25OHD levels below 10ng ml, and so have poor bone health.   Doctors generally think of deficiency being below 20ng/ml - but this is just for bone health.

The second role of circulating 25OHD is the one everyone needs to understand, since it concerns all aspects of the immune system, as well as a large number of other cell types which have not yet been so well researched.   Very few MDs understand this, since it was discovered in the mid-2000s.

In this role, circulating 25OHD is used by numerous cell types, all over the body, to be converted inside the cell to 1,25OHD, for the purpose of activating vitamin D receptors inside the cell, to alter gene expression and so protein synthesis and the whole operation of that particular cell.  This is autocrine signaling - a form of signaling which occurs entirely within the cell.  

Other types of molecules are involved in other autocrine signaling arrangements and here we are only interested in 25OHD being converted to 1,25OHD.  This autocrine signaling is not to maintain a steady state, such as with calcium- bone or some other bodily system.   The autocrine signaling conversion to 1,25OHD is only turned on in particular circumstances.  So vitamin D based autocrine signaling is a crucial part of how most immune cell types, and many other cell types, respond to their changing circumstances.  This has nothing to do with hormonal signaling.  The levels of 1,25OHD produced inside the cell are much higher than the very low levels of hormonal circulating 1,25OHD.  The half-life of 1,25OHD inside the cell is short - probably hours or less - since enzymes there degrade it.

Paracrine signaling is a closely related signaling system in which 1,25OHD, produced in a cell from 25OHD - as for, or as part of, autocrine signaling - diffuses out of the cell and to nearby (millimetres) cells, which sense its level and alter their behavior accordingly.

Since I couldn't find a good, illustrated, tutorial on autocrine and paracrine signaling, I made this page:

adapting illustrations from a 2011 article by Martin Hewison and colleagues, in which they report their discoveries.   If you have time, please read this page and at least some parts of the research articles it cites.   If you have understood the current page so far, you know more about vitamin D autocrine and paracrine signaling than the great majority of doctors.  By  reading and understanding the 02-autocrine page, you will attain a still better understanding of these processes.   It includes references to research which:
Once you understand vitamin D autocrine / paracrine signaling, the need for 50ng/ml or more circulating 25OHD for it to work properly, how many types of immune cell need such levels to work properly (those cell types which directly attack pathogens, develop antibodies and correctly regulate potentially self-destructive inflammatory immune responses), then it is clear why low vitamin D drives the development of severe COVID-19 and why a tiny quantity of calcifediol is so extraordinarily effective at preventing hospitalised COVID-19 patients from progressing to full-blown severe, cytokine storm, endothelial cell destruction, hypercoagulative blood, micro-embolism and larger blood clot, severe COVID-19.

If you are keen, you will find links to and summaries of dozens of research article here at and at its more extensive and less well organised companion .  Please also see and the meta-analysis of the latest vitamin D intervention and observational studies concerning COVID-19:

Those with the most inquiring minds will want to know why humans, domestic animals and agricultural animals suffer, generally and according to  considerable genetic variation, from such a large number of overly-inflammatory conditions.  The answer is that we have no longer are infested by helminths (intestinal worms): .

There are a plethora of reasons why everyone should supplement vitamin D3 to aim for 25OHD levels of 50ng/ml or so.   For suggestions for how much D3 to take, on average (it is generally regarded as OK to have larger intakes up to a week apart), depending on body weight and morphology (obese people need more D3 per kg bodyweight), please see:

Long-term supplementation along these lines raises circulating 25OHD over a week or two, and then over a few months, to a final healthy steady state, all year round.  

For most people, this is fine and there is no need for them to think about calcifediol = 25OHD.

However, if a person is suffering from, or at significant risk of developing,any one of these conditions:
then it is likely that their circulating 25OHD levels are dangerously low and have been for weeks or months.  (Also, these infections can marginally reduce these levels, presumably due to 25OHD being consumed by immune cells' autocrine and paracrine signaling systems.)

Without rapid repletion of their 25OHD, they will be at high risk of serious harm and death - depending on the success of any anti-inflammatory drugs, which all MDs and nurses use at present to tackle these emergencies.  MDs and nurses also tackle other problems such as high or low blood pressure.   (Anti-inflammatory drugs such as the corticosteroids prednisolone [WP] and dexamethasone [WP] carry significant risks, including of psychosis and raising blood glucose.  Their use for COVID-19 in India for people suffering from type 1 diabetes has lead to some people developing "black fungus" mucormycosis infections, including of the eye, which is frequently fatal: .)

Bolus (stoss) D3 supplementation usually helps - such as a single 5mg 200,000IU dose or several such doses over a few days.  But these people need their 25OHD levels raised now, not in days or a week or so.

Such brief, higher than normal, D3 intakes, or the ~1mg single dose oral calcifediol discussed below - are unlikely to cause any harm, even if someone has been supplementing higher than ideal D3 levels for months.  So there's no need for a 25OHD blood test, unless perhaps the results can be known in a few minutes.  Time is of the essence and the sooner their 25OHD level is raised the better chance the person has of overcoming any pathogens and what might otherwise be a progression to self-harming hyper-inflammatory immune system dysregulation.


Calcifediol is a magic bullet, but until early 2021, has been extremely difficult to obtain

Magic bullet is a strong term in medicine.   I am just an electronic technician, and you should make up your own minds about all this, after reading the research yourself, rather than rely on my opinions.  However, I think it is reasonable to regard a milligram or so of calcifediol, as a one-off oral dose (with continuing support with D3 in the days which follow), as a magic bullet when tackling the conditions listed above, all of which are made very much worse by low circulating 25OHD levels.  Most likely if the person had good vitamin D levels of 50ng/ml or so, they would not have become ill in the first place.

0.532mg of oral calcifediol (in oil-filled capsules, which improves absorption from the intestine into the bloodstream) provided dramatic benefits to the hospitalised COVID-19 patients in Cordoba (Castillo et al., above).

The purpose of the rest of this page is to discuss how such single dose calcifediol treatments can do much the same magic bullet work as in Cordoba, in the abovementioned emergency medical conditions, where the primary, correctable, problem is low vitamin D: low circulating (blood) levels of 25OHD 25-hydroxyvitamin D.

Assuming the person is conscious and can ingest liquids, all we need to do is give them 0.5 mg to perhaps 2mg (for obese adults) oral calcifediol, ideally with some oil to aid absorption, and we will have their 25OHD levels high enough to meet the needs of all their immune cells, within a few hours.  (In principle injections or IV drips could be used as well, but this page concerns solely oral calcifediol.)

Rayaldee from the USA

When I started advocating one-off, 1 milligram or so, calcifediol oral intervention in the middle of 2020, calcifediol was very hard to obtain.  As far as I know, the only option in the USA (and perhaps Canada) was the prescription capsules "Rayaldee".   As detailed at  a packet of Rayaldee contains 30 capsules, each containing 30 micrograms = 0.03mg of calcifediol.  Since each packet costs USD$1,206.88, this is USD$1,340.98 per milligram.

(Lab grade calcifediol is also available but MDs would probably have to break regulations and so threaten their career of they did not use pharma grade - though with these tiny quantities, the lab grade calcifediol would be just as effective and with no possibly significant quantity of impurities.  Likewise, almost certainly, the much cheaper agricultural feed products I researched at: where a bucket of poultry water feed powder costs about USD$100 and contains 1.875 grams of calcifediol. This is USD$0.0533 per miligram.

Hidroferol from Spain and Neodiro from Italy

Until early 2021, to the best of my knowledge, the only other source of pharma-grade calcifediol ready for oral use in patients was the oil-filled capsules and glass ampoule forms of Hidroferol, the awkward trade name of long-established Spanish company Faes Farma.   More details at: .

However, in May 2021, I was told of Italian Neodiro, which are very similar or perhaps identical capsules, also prescription only, which are available for €10 for 10 capsules of 0.266mg each.  This is about USD$12.14 and so USD$5.64 per milligram.  More details at: .  

The 15 capsules, each containing 0.266mg calcifediol, were used in the Cordoba trial, so we know these are good.  The patients recieved two such capsules at the earliest opportunity, and then one capsule on days 3, 7, 14, 21 etc.   It is the first two capsules which made all the difference.  The subsequent smaller doses would have maintained the newly boosted circulating 25OHD levels perfectly well, but regular vitamin D3 capsules, averaging (for 70kg adults) 0.125mg 5000 IU per day (, would have maintained these levels just as well.

As far as I know these are available within Spain.  They seem to be available from pharmacies in Georgia (the country, not the US state).  The  43.71 Gel price for ten capsules equates to about USD$14.

If we assume a price of USD$15, for 10 x 0.266 = 2.66mg, then this is USD$5.64 per milligram.  This is the best price I know of for pharma grade calcifediol.  The challenges are having a prescription for it, finding a seller who will export it to the country of interest, and getting it through customs.

Here is my infographic showing the rise in circulating 25OHD in health volunteers after ingesting two Hidroferol capsules - the same as the initial dose in the Cordoba trail:

The original version of this graph is from the end of the PDF version of this patent by Faes Farma:

Calcifediol soft capsules
Josep María SUÑÉ NEGRE,
Ignacio Ortega Azpitarte, Pepa Del Arenal Barrios, Gonzalo HERNÁNDEZ HERRERO
WIPO WO 2016/124724 A
l   2016-08-11

DSM's Fortaro, for customers in Australia

In late February 2021, leading Dutch human and animal feed supplement manufacturer DSM ( , WP)  launched Fortaro with online sales, no prescription required, for customers in Australia.  I bought some and you can read all about it at:

Each bottle costs about USD$20 and contains 60 small (150mg) tablets, each with 10ug 0.01mg calcifediol per tablet.  So a bottle contains 0.6mg calcifediol, making this USD$33.33 per milligram.


DSM's d.velop for customers in Canada and the USA

In late April 2021 DSM launched a similar product d.velop for online sales, with no prescription required, for customers in the USA and Canada:

  1. There are numerous packet forwarding companies in the USA - such as the one I use: - who can either purchase items from sellers or ship packages to you in other countries if you buy them directly with delivery to their warehouse.

  2. The product is labeled as "Vitamin D", is presumably made in the USA and is non-prescription in the USA, so I expect there would be few difficulties getting these into countries such as Australia.
I believe that this product is available, in practical terms, to anyone who wants it, no matter which country they live in.

Each packet contains 60 tablets each with 20ug 0.02mg calcifediol.  This is 1.2mg calcifediol for USD$30 including shipping within the USA.   So this is USD$25 per milligram.

I ordered 3 packets, which were sent to in California and they have posted the package to me using USPS.  (Their cheapest shipping option uses AusPost, who apparently won't handle packages containing nutritional supplements.)   I will post some photos and other details here when they arrive.


How much calcifediol to use, as a ratio of bodyweight?

In this emergency vitamin D repletion scenario, we would be using these products quite differently to the daily (or twice daily for d.velop) use the manufacturer recommends.   So we would be taking full responsibility for our actions.

Assuming plenty of calcifediol is available, I tried to arrive at a micrograms per kg bodyweight ratio, which would be helpful for everyone, from babies to sumo wrestlers.  I consulted with Prof. Sunil Wimalawansa MD, of New Jersey (long-time vitamin D researcher CV, Google Scholar) he advised that 14 micograms per kg bodyweight would be a good ratio to use. 

This is about double the micograms / kg bodyweight which was so successful in the Cordoba trial and is 1mg for a 70kg person.   Doubling the amount per kg gives some allowance for poor absorption and people suffering from obesity, for whom it is more difficult to raise their circulating 25OHD levels due to excessive fat absorption.  

1mg of calcifediol is very approximately as effective, in long-term use, for raising circulating 25OHD levels as as 3 times this amount of D3.  On this basis, 1mg is roughly equivalent to 3mg 120,000 IU vitamin D3 cholecalciferol.   This is would be a small bolus D3 dose, and the Cordoba patients did well with half this.

Since this is a single dose, there is no risk of toxicity unless perhaps the person had been excessively supplementing D3 for months.  If so, their circulating 25OHD levels would be very high and they are unlikely to be in hospital with COVID-19, sepsis, Kawasaki disease etc.

Due to the urgency of the situation, with the person's life perhaps hanging in the balance, it makes sense to do a proper job of repleting circulating 25OHD levels in a way which will still be effective if obesity and/or marginally poor absorption are problems.

So a 70kg person would get 1.0 mg = 50 d.velop tablets at a cost of USD$25.  This is a good deal considering how serious all the above conditions could be.  Even if it made only a barely perceptible difference of a few percent to the outcomes, it would be a good deal.  In Cordoba, with presumably some or many of the patients suffering from obesity, and so with bodyweights well over 70kg, 0.532mg (27 d.velop tablets costing USD$13.30) lead to a huge reduction in symptoms, suffering and need for intensive care.  This would have been around 6 micograms per kg bodyweight.

If the calcifediol was available on only limited quantities, I suggest distributing it evenly over multiple people according to their bodyweight and probably risk of serious harm.   Any amount will help. 

0.014mg calcifediol per kg bodyweight is an approximate recommendation, not some critical ratio to be adhered to closely.  It would be fine to remember:

55 to 85kg: 1mg calcifediol

which covers most adults and older adolescents.  For babies and children, the frail, overweight and obese adults outside this range, 0.014mg / kg is good guidance.

Another way of thinking about it, with d.velop 0.02mg tablets is:

Multiply the bodyweight in kg by 0.7 to get the number of tablets.

For Fortaro 0.01mg tablets, multiply the bodyweight in kg by 1.4.

Please see this section, which I wrote  before these two DSM product releases.  I suggest a single calcifediol dose followed by robust D3 supplementation in the days, weeks and years which follow:

I suggest taking D3 and calcifediol with some oil, such as fish oil, or at least towards the end of a substantial meal which contains fat, to activate the fat absorptoin mechanisms in the upper intestines.   Don't wash it down with a lot of water or any other drink.  

Please remember that you are reading the best efforts of an electronic technician - not a doctor!   My interest in these Fortaro and d.velop tablets is to use several dozen of them at once, which is completely different to how these products are intended to be used.   If you do this, it your decision.   Don't complain to me or DSM if something bad seems to have occurred due to using this product in ways other than they intend.

There are a few things to remember about these excellent DSM products - and of Hidroferol and Neodiro:
  1. Despite the claims of DSM that Fortaro and d.velop have advantages over D3 for long-term supplementation, I see no reason to believe this - unless it could somehow be shown that particular individuals had significant absorption problems for D3 and or liver conversion problems, with no such absorption problems for calcifediol.

  2. While these calcifediol tablets and capsules would work for long-term supplementation, they are a lot more expensive than alternatives such as 100 1.25mg 50,000 IU capsules for USD$30: .  (Tina and I take one a week - so 0.179mg 7143IU a day.)   USD$30 buys 125mg D3.  For the same price, 60 d.velop tablets provide a total of 1.2mg calcifediol.  Assuming we accept the 3:1 ratio suggested by DSM, this is equivalent to only 3.6mg D3, making d.velop 35 times more expensive than these BioTech Pharmacal D3 capsules.

  3. The only reason I am interested in these products is for one-off emergency vitamin D repletion.  This means they must be purchased ahead of time in anticipation of someone becoming ill with one of the abovementioned conditions.   At a pinch, one might use D3 to start with, order the calcifediol product and use it as soon as it arrives.  

  4. Most doctors know little or nothing about all the research mentioned on this page, so they might be opposed to the suggestions here.  Please have them read this page and hopefully at least look a the research articles cited here.

© 2021 Robin Whittle   Daylesford, Victoria, Australia