Vitamin C injections and cancer: perceptions vs reality


(Note : This is a translation of the original article that was published on my main website in 2018. At the time, it was only available in French; I translated it afterwards so that my anglophone colleagues could read it. Robyn Penney made edits to the translation)


In May 2018, a petition signed by more than 70,000 people was submitted to the National Assembly of Quebec, with the goal of « authorizing » Vitamin C injection therapy for cancer patients. When asked about the petition, the Minister of Health at the time then said that, according to oncologists, this type of intervention « had no added clinical value« .

A second petition, started in January 2019, collected more than 120,000 signatures, and went even further to ask that  Vitamin C injections be added to the list of medications covered by the Public Prescription Drug Insurance Plan. It received a lot of positive media coverage and was advocated by many influential public figures.


People living with cancer go through extremely difficult times and need a lot of courage. Some have received Vitamin C injections before, and they believe it helps them better tolerate chemotherapy. I sincerely hope that these people will be able to keep receiving their injections.

However, there’s a much bigger issue at stake here.

The problem isn’t that a few people are receiving injections. The problem is that all the buzz surrounding this petition makes it seem as though Vitamin C injections should become a prevalent, readily accessible treatment for cancer patients. That’s simply not a good idea.

Unfortunately, from the online comments on the petition and the news articles covering it, it is obvious that many people don’t understand the real issues at play. And I can’t blame them; it’s actually quite hard to grasp the facts here, especially if you rely on social networks and the media for information.

This article thus aims to show where popular perceptions of Vitamin C injections diverge from reality.

(Note: The comments presented below are real and quoted verbatim)








Vitamin C injections are not a cure for cancer.

The suggested indication is to reduce the side effects of chemotherapy, to improve patients’ quality of life. And unfortunately, to date, the data are not conclusive for this use either.

(In other words, there are some positive trials, and some negative ones… but these trials do not have an adequate placebo group that would tell whether the effect is actually due to Vitamin C; or their design does not allow researchers to draw real conclusions about the effectiveness of the treatment. So overall, the efficacy is not clear and remains hypothetical: see here, here, here and here among others).


The belief that Vitamin C cures all kinds of diseases dates back to the 1970s, but it proved to be wrong when assessed scientifically.

As far as we know, the only thing that is cured with Vitamin C injections is scurvy – a concern in Jacques Cartier’s era, but relatively uncommon nowadays.


vitamin c scurvy







It is not « illegal » to inject Vitamin C in Quebec, even for cancer.

The issue is not legality, but the fact that it is not ethical, rational or justifiable to do so in the absence of solid scientific evidence.

Importantly, it’s no more acceptable in Ontario than in Quebec. The media mentioned an Ontarian clinic offering these injections which wasn’t, in fact, a medical clinic, but a center for « integrative medicine » (i.e., the new name given to complementary and alternative therapies). Its founder and executive director is a naturopath. According to its website, it seems that only one physician practices there, and she is not an oncologist.

In short, the fact that Vitamin C injections are offered by clinics in Ontario, the rest of Canada, and the United States (where there are many), that doesn’t prove their efficacy. 






A lot of comments try to make a link between Vitamin C and the legalization of cannabis. But again, there‘s no question of « legalizing » anything, so this comparison doesn’t hold water.






Vitamin C injections typically don’t seem to cause many side effects – that much is true.

But here’s the real problem: preliminary data suggest that Vitamin C could interfere with the effectiveness of chemotherapy.

[When chemo is administered for incurable cancers (e.g., palliative care), it’s not to treat the cancer, but to reduce pain and prolong life expectancy. So we should take seriously the possibility that Vitamin C decreases the effectiveness of chemo in these cases.]

Clinics offering such injections even say so in their references:



Trials with oral Vitamin C had to be stopped prematurely because of the toxic effects that appeared to be caused by vitamin itself.

Actually, this isn’t surprising. Vitamin C is an antioxidant, but some have suggested based on in vitro data that it may also have the opposite effect (i.e., pro-oxidant). In the human body, these reactions are subject to a very delicate balance, and the ultimate effects they could have on our health are still not known and therefore largely unpredictable.

In short, it’s a mistake to see these injections as harmless. And at any rate, administering megadoses of vitamins is always dangerous.

Meanwhile, we know that people with cancer who use alternative / complementary / integrative therapies are at higher risk of dying from the illness. We’re talking about a 2- to 6-times higher risk of mortality (see here, here and here).

If we ‘re going to accept preliminary data suggesting efficacy, we should also accept preliminary data suggesting potential hazards.







Chantal Lacroix is a TV host and public figure known for her involvement in social and humanitarian causes. For that, I applaud her.

But her comments regarding the petition – for which she’s been a major advocate – are somewhat… peculiar.

The professional oath taken by doctors requires them to « [practice] medicine according to the rules of science ». And that’s exactly what they’re trying to do.
Prescribing an unproven and potentially risky treatment – wouldn’t that be “flouting the Hippocratic Oath »? Is that somehow ironic too? (At this point I’m a little confused as to what constitutes irony…).

In short, it’s unfortunate that someone as influential as Ms. Lacroix is choosing to promote a cause by discrediting the medical community through unsubstantiated claims.

Others bring this idea even further:






Ok, let’s try to unpack this one using logic.



In fact, one Quebec woman who is currently receiving Vitamin C injections explained on a radio show that these treatments have allowed her to stay longer on chemotherapy.

In other words, if Vitamin C injections work, they should ultimately be profitable for Big Pharma.







Actually, natural health products are a multi-billion dollar industry. There’s a lot of money to be made, despite extremely poor regulation.

According to the information I was able to collect:



That’s pricey, and not accessible for everyone.

OK, it’s a drop in the bucket compared to the billions of dollars generated by the industry, but for a therapist or a clinic with many patients, there are tens or even hundreds of thousands of dollars to be made each year.

(To be clear, I’m not accusing these therapists and clinics of administering Vitamin C to make money, but simply pointing out that yes, it can generate significant profits).







That’s what the United States just decided.

The Right to Try Act, signed by Trump in May 2018, grants terminally ill patients access to any experimental treatment, regardless of its efficacy or safety.




At first glance, it may seem like a good idea …

What it obscures is that terminally ill patients, both in the US and Canada, already have special access to experimental treatments. But only those that seem to work.

When they go through Right to Try, patients essentially become guinea pigs for scientifically unsupported therapies, with no basic rights in case of complications. They can easily become targets for charlatans ready to sell a miracle therapy (it’s already happened elsewhere). And nobody can be held responsible.

For the protection of patients and the public at large, I hope we will not go this route in Canada.







(excuse my cheesy title design… just couldn’t help myself!)


I completely understand those who are committed to this cause. In fact, everything relating to the topic of cancer is enormously important to me.

I realize that in talking about this subject in such a matter-of-fact way – while also making jokes to lighten the tone – I probably sound (to some people) closed-minded or even insensitive.

But one of the essential messages I am trying to convey through The Pharmafist / Le Pharmachien is that applying the scientific approach to our health choices is one of the most helpful things we can do as a society, especially for those in a vulnerable position.

What I find most unfortunate here is that many people will continue to find the situation unfair. I understand why it may seem that way. But when we choose to support a cause, we have a responsibility to fully understand what’s at stake, and to not simply select the facts that do or don’t fit our story.

If Vitamin C injections really had « proven » benefits, they would be prescribed regularly in oncology, because everyone – the patients, doctors, and industry – would be a winner.

Yes, some people may derive benefits from them (whether real or a placebo effect). But to this day, Vitamin C remains a treatment with potential risks and unclear benefits, so it makes sense to use it rarely or not at all.  At the moment, it’s in the best interest of cancer patients.


P.S. I did a mini-investigation and found an oncologist in Montreal who’s prescribing Vitamin C injections for cancer. Despite all my efforts to get his name, he wants to remain anonymous…which is really strange, considering that he is allegedly heading an oncology research center (not locatable on Google) that is about to start a clinical trial (not found on any registry) on Vitamin C injections. I found the phone number of the center and I spoke to his coordinator, a very kind woman who said to me: « I know who you are, and I know you don’t really believe in this kind of thing… » Well, I won’t need to « believe » once the results of the clinical trial are published and available to be analyzed. In the meantime, I think we should remain skeptical and cautious.




*** UPDATE – JANUARY 21, 2019 ***

A new version of the petition is in circulation. Once again, it’s asking to « authorize doctors to prescribe Vitamin C », but also to include it on the list of covered medications, as well as proposing « to set up a Vitamin C injection registry in Quebec.” The petition was promoted on national TV, on the popular show « Tout le monde en parle« , on January 20, 2019.

Some further thoughts and info on this topic:




*** UPDATE – JANUARY 30, 2019 ***

The Chief Scientist of Quebec also commented with a similar view on the topic.





*** UPDATE – FEBRUARY 5, 2019 ***

Some people are promoting a news item stating that Sherbrooke University has received a $2.8 million grant to study Vitamin C injections.

That’s true … but it’s for a totally different indication, namely, septic shock (a serious complication of certain infections). It involves studying a completely different mechanism of action and cannot lead to any links with cancer at this stage.




*** UPDATE – FEBRUARY 11, 2019 ***

Science journalist Jean-François Cliche inquired with the Ontario Ministry of Health regarding their position on the use of Vitamin C injections for cancer patients. Unsurprisingly, but contrary to what is stated in the petition, this practice is not considered scientifically nor ethically acceptable in Ontario, either.





*** UPDATE – FEBRUARY 15, 2019 ***

Proponents of the petition are now citing a new article to support their claims. However, contrary to what its title suggests, it refers to an in vitro experiment on cells, the results of which are important for encouraging future research, but cannot be extrapolated to humans. The article also alludes to a phase I trial with 11 participants that aimed to assess the safety of Vitamin C injections (also called a « safety trial »). This study is never referenced in the article, which is very bizarre…I presume that it was never published, and therefore it is impossible to analyze or interpret it (I wrote to the editors of the site for more information). But regardless, this type of study cannot assess 1) the effectiveness of treatment, nor 2) the risk of reducing the effects of chemotherapy (because the duration of the study was too short, i.e., 2 months).

When asked about the above, the author of the article in question objected to her text being used in support of the petition, stating:

« I and Cancer Commons have never endorsed [this] position / petition and asked [the organizer] to remove the post from Facebook. While there are some data to support high-dose Vitamin C, they are not conclusive. Cancer Commons’ name has been used without permission. »






*** UPDATE – FEBRUARY 20, 2019 ***

Proponents of the petition have adopted a new (and visibly effective) strategy over the past few days, presumably in the final sprint before filing to the Quebec National Assembly on February 28, 2019. Yesterday, Ms. Chantal Lacroix published a video summarizing the group’s current arguments. It’s worth analyzing to illustrate how useful critical thinking principles can be in this type of debate. The video in question…

  1. Continues to spread the idea that Vitamin C injections are « illegal, » and that the petition is intended to « legalize » them. This fallacious argument is called ambiguity of language; legalizing, or even authorizing anything, in not an issue here, as explained in my article.
  1. Implies that if Vitamin C injections are not « legalized, » people with cancer may need to turn to physician-assisted suicide, which is legal. On the one hand, this comparison is tasteless, inappropriate and indelicate towards the terminally ill. On the other hand, it is a false dilemma, giving the impression that a person may have to choose between these two options, which is not the case. Above all, this is a bad analogy because both interventions are considered in very different contexts.
  1. Adds that dozens of public figures from the artistic world have signed the petition in the last few days, which – according to them – demonstrates the validity of the requests. This is an appeal to popularity; the fact that many people or celebrities sign the petition doesn’t guarantee anything.
  1. States that « leading experts » in the field of cancer have signed the petition. First, no such expert has endorsed the petition publicly, to my knowledge. But above all, it is an appeal to authority; even if some « leading experts » had signed the petition, this would not guarantee its validity.
  1. States that even if scientific data on Vitamin C injections are lacking, « everyone wins » by signing the petition, as it will allow more data to be collected through the creation of a clinical registry. This statement is false because creating a registry is no substitute for clinical research, which is necessary in this case. Clinical registries in Canada are a series of anecdotes collected in uncontrolled environments, from which we cannot draw conclusions about the effectiveness of an intervention. Drug registries identify certain side effects that appear to occur more frequently, which may result in increased government and manufacturer vigilance, and may lead to the development of additional clinical studies. In short, creating a registry for Vitamin C injections would only be relevant if this intervention was already supported by convincing data and therefore was considered scientifically and ethically acceptable by oncologists.

This is not the first time that Ms. Lacroix has ignored criticism coming from scientists or that she is promoting questionable health practices. She is obviously well-intentions, and I do not doubt her sincerity in this process. But again, I would like to invite her to be more cautious and restrained when it comes to health topics, given her vast popularity and influence.




*** UPDATE – FEBRUARY 28, 2019 ***

Youri Chassin, the local deputy supporting the petition, is now calling for a special parliamentary committee on Vitamin C injections. So I contacted him directly on his Facebook page: 

(the following is an image modified in order to include the translation in French)


I did not get an answer, even when following up with his office by email. However, Mr Chassin answered this to another user:


Mr Chassin later deleted his post from Facebook.





*** UPDATE – MARCH 1, 2019 ***

I explained above why, in my opinion, the creation of a clinical registry for Vitamin C injections is not appropriate, but I realize that I did not explain why I think the same about a parliamentary committee.

According to the National Assembly of Quebec, « Parliamentary committees are the perfect forum to examine bills or other current issues in detail. The deputies also play a role in controlling government activity and in public consultation on various current social issues.

I have no doubt that these committees are relevant for issues of public interest that are subject to a debate of opinion. But in this case, there is a lack of evidence to support the use of Vitamin C injections for people with cancer. In other words, the issue is not a matter of opinion, but of science.

A committee will not generate new data on the effectiveness and safety of the treatment. And even if the goal was to discuss funding for a possible clinical study on Vitamin C injections, how could one justify awarding research funds, so hard to obtain, on the basis of the popularity of a petition? It is not up to a parliamentary committee to decide on the funding of clinical research, but rather to organizations specialized in this field, such as the Quebec Health Research Fund (FRSQ), or the Canadian Institutes of Health Research (CIHR).

It should be noted that, to this day, NO experts have publicly endorsed this treatment.

Also note that during a parliamentary committee on Lyme disease in March 2018, the National Assembly of Quebec summoned as key expert a French doctor who attributes the spread of Lyme disease to an exiled Nazi researcher genetically modifying ticks for the US military. This gives you an idea of how this type of committee sets its standards regarding « key experts » …

In summary, creating a parliamentary committee to discuss such a niche medical issue, which above all requires critical analysis of the evidence, is in my opinion a political lobbying strategy that bypasses the scientific process, thereby creating significant risks for the healthcare system and the field of medicine. It is also, in my opinion, a poor investment of public money, considering that very little scientifically and clinically relevant information can be obtained from such a committee.

Note: I’m far from being a political expert, so if I’m wrong regarding the above, I would welcome specific arguments to make me reconsider my position. To date, I haven’t received any.






*** UPDATE – MARCH 4, 2019 ***

So here’s what’s happening right now


And as promised, here is the entirety of my conversation with the creator of the petition in 2018.





*** UPDATE – MARCH 21, 2019 ***

At last! Experts have decided to come forward on the science behind Vitamin C injections, in light of what’s going on right now:


I also want to tell you how touched I’ve been by all the support I have received in recent days. It would be impossible for me to answer everyone, but I want you to know that I have read your messages and that I am deeply grateful.

I also want to say a huge thank you to my broadcaster and to the Quebec Order of Pharmacists, who understand the situation and offered me their support. I consider myself very lucky.

I also thank all the scientists, healthcare professionals and scientific and medical associations who have decided to come forward. Such complex subjects deserve a joint effort of communication.

You will understand that given the gravity of the situation, I cannot / do not want to comment on it.

But putting aside my case, as many have guessed, it’s not so much « me » that needs to be defended: it’s the scientific process. Discussing science publicly is now harder than ever, and we should not let things devolve to the point where it’s no longer possible at all.

On a more cheerful note, this case has inspired serious reflection about the involvement of scientists in public debates and how to support them in the current climate. A few projects are already germinating, and I hope they will come to fruition soon; stay tuned for updates below.

Thank you again, everyone, I appreciate your support so much!





*** UPDATE – APRIL 4, 2019 ***


Click here to read about the decision of the Government of Quebec in detail.

More media coverage can be read here.




*** UPDATE – MAY 1, 2019 ***

I can now confirm that some positive outcomes have emerged from this case:

  • A government task force (which I am fortunate enough to be involved in) was created in order to protect scientists who speak publicly about sensitive topics.

  • Also, an inter-professional advisory committee was created by several professional Orders to support healthcare professionals such as myself when they speak publicly, so they can do so without fear of disciplinary action.


It is comforting to know that despite the negative events in this case, there are some positive repercussions. I hope these initiatives will help others avoid situations like the one I experienced.




*** UPDATE – JUNE 13, 2019 ***

Back in March 2019, in response to the public controversy surrounding Vitamin C injections, several professional associations submitted a joint request to mandate the National Institute of Excellence in Health and Social Services (INESSS) to write an official report on their clinical relevance. This is now official and will be carried out. An INESSS mandate is precisely what I was hoping for from the start, so I see this as the best possible outcome.




*** UPDATE – NOV. 12, 2019 ***

It is with great surprise, gratitude and emotion that I have received last week, in London, the John Maddox Prize for my work on the topic of Vitamin C injections in Quebec.




*** UPDATE – MAY. 31, 2022 ***

The National Institute of Excellence in Health and Social Services (INESSS) published their report today on high-dose vitamin C injections for cancer patients in Quebec. It is an extremely thorough evaluation, in the form of a systematic review. The main conclusion is :

« In light of all the information available and in the absence of a demonstration of clinical efficacy, INESSS is of the opinion that high-dose vitamin C should not be offered to people with cancer, regardless of the therapeutic goal sought. This treatment modality should only be offered in the context of a clinical trial. »






Many thanks to all of you for your interest in this topic!


To read about the original version of this story in French (which includes about a hundred comments and my answers), see here.


Joindre la conversation

  1. I just read that you were awarded the « prestigious John Maddox prize » for enduring a barrage of harassment over this issue, and according to wikipedia: IVC enthusiasts leaked private details about you to the public (aka « doxing ») making you the subject of even greater harassment. I am very saddened to hear that happened.

    I’ve taught probably 100 doctors or more, at my own expense, about the right way to encourage « quality IVC research ». Bullying people like you undoes a large amount of goodwill that I’ve been working to establish for many years. Although we differ in our IVC opinions *nobody* should ever be harassed or attacked like that. I’m very sorry.

    I know that we can agree that IVC is perhaps complementary-medicine’s most passionately championed therapy, the brunt of that which you’ve experienced first hand. From the scale of that passion … and consider all the people getting IVC for deadly conditions, can you grasp just how much money is wasted, and lives lost?

    Maybe we need a *proper* study, that would produce quality data … you know RDBPC, best-advocate protocols, large study population, tight controls. Quality work.

    Currently there are over 200 studies published in NIH indexed peer-reviewed articles on cancer-IVC, and I’ve read them all. About 80% look favorable for IVC, but are comprised of what is called low-quality data. That’s fair. Your anti-IVC position is based exclusively on the other 20% of cancer-IVC studies, most which demonstrate no benefit, and very few (many which look problematic when you dig into them, like drinking soda’s during IVC, or using very low doses, using fully oxidized IVC, etc) seem to demonstrate some risk (although relatively small compared to most cancer drugs). Also that 20% of studies is comprised of the same low-quality data used in the other 80% favorable studies. Quality is expensive. About $80M. And IVC researchers are relatively poor.

    Further to your credit most of your favored studies are comprehensive reviews which state (and all of them state this) that IVC is not recommended due to the paucity of « quality » data, which is another way of saying no studies were done to the gold standard of RDBPC with very large populations and very tight controls.

    Again, this is fair. I’m not advocating for a gold stamp on something that isn’t tested to a gold standard, nor am I even petitioning for coverage … not yet. The gold-standard data is not there because it hasn’t been tested.

    Given how much is spent on an unproven treatment (esp. if it’s risky) does it not then stand to reason that public health funding should put the issue to rest? By funding a *proper* study? Isn’t that the responsible thing to do? For the public. Have the data to make it justifiably illegal. To save them from their own selves. If you’re right about IVC, then that’s exactly what we should do. A *proper* study.

    *Properly* test their best-practice (Hunninghake/Levy) protocol! Prove them wrong, *properly*, not just quoting comprehensive reviews that says we don’t really know if it’s good so don’t do it. Shut the advocates up once and for all. I’m trying to appeal to your sense of reason, of course (as a researcher I’m sure a *proper* study will strongly contradict your opinions on IVC).

    Really if you don’t then you’re on thin ice, intellectually. As it is, by the admission of QW and SBM their position (which is yours) is supported only by non-quality data (data of the same non-gold caliber used by IVC-favorable studies). Only by funding a *proper* study will you improve your position.

    Let’s put this issue to rest, either vindicated, or dead. Use your influence to fund a study to know what’s really happening, and not be satisfied with simply rejecting something out of willful ignorance. It will cost a lot of money but if as many people are wasting $ on this, and loosing lives over this, as you say then it would be unconscionable to not get the data necessary to make it an illegal practice.

    Now I hope that isn’t more bullying, or harassing, and I honestly mean that. I want to strengthen your position in the event that you’re right (or weaken it in the event you’re wrong). Only by helping fund a proper $80M study will that get done. It’s done for every pharmaceutical substance to protect the public, even though they are not available. IVC however is *ALREADY* used, the darling of alternative medicine, and it’s legal, an according to you killing people faster and making the poor even poorer. If you’re right then you can change that and you should.

    • Hi David!

      Thanks so much for your insightful comment & nice words!

      As you say, my position on IVC is that of the medical associations in the field, namely that there is a lack is quality evidence to recommend this type of therapy for people with cancer. So to answer your question, yes, I am absolutely looking forward to better research and data on the topic, upon which the scientific community could reassess its position.

      Now the part where I don’t completely agree is the idea that should prioritize funding for a proper IVC trial. There are tons of issues in healthcare which require better data, and researchers are struggling to acquire funding. For this reason, it would not be acceptable or ethical, in my opinion, to fund a trial based on whether a topic is popular or not, or whether there is public pressure to do it (ex. the petition). Here in Canada, we have bodies which are responsible for allocating research funding, like the Canadian Institutes of Health Research, and I am sure that there are a lot of factors to consider.

      It turns out that there are uses of IVC that seem promising and that are being studied/funded, like this 2018 research project at Sherbrooke University on septic shock:

      Again, I hope we’ll get better trials, and I’m actually hopeful we will. I’ll be following up on this topic as it’s become dear to me throughout this story.

      Take care,


      P.S. You’ll notice that I’ve moved your comment to my English website! Discussions will be easier this way 😀

  2. We had an issue in Saskatchewan a number of years back with respect to the unproven Zamboni treatment for Multiple Sclerosis. Health Canada stated the treatment wasn’t proven to be effective for anything, but our provincial government approved money for ‘treatment trials’ because it was apparently politically popular. At the end of it all, it did prove to have no effectiveness. It wasted provincial money, disrespected the work of qualified researchers, and worst of all, I think raised false hope among those suffering from the disease. It is truly sad that the scientific method as a process has taken such a beating and that you got caught up in it.

    • Hi Richard!

      This is a tremendously relevant example: because of popular pressure, the Zamboni protocol was adopted by many healthcare professionals before it could be properly tested. And when the results finally came in, it was a devastating blow to hopeful patients, and it looked pretty bad for doctors who believed Zamboni without the evidence. This should be a cautionary tale.

      Thanks so much for your comment!


  3. I have a friend who has had cancer for 10 years, has refused conventional treatments and was treating herself with only IV high dose vitamin C. She had to move to British Columbia to be treated because you cannot get IV vitamin C in Quebec (unless an oncologist prescribes it). Doctors are allowed to try plasma injections when they get covid so why can’t cancer patients try IV high dose vitamin C in Quebec.

Laissez un commentaire

Laisser un commentaire

Ton commentaire n'apparaîtra pas immédiatement, je dois les approuver manuellement!

Back to top