The latest Vitamin C scam

True facts about Vitamin C:

  • It is an effective antioxidant, and can donate electrons to free radicals to neutralize them.
  • Topical Vitamin C is helpful in providing photoprotection.
  • It’s also a depigmenting agent — it can decrease melanin formation in the skin.

  • Vitamin C can neutralize the chlorine in chlorinated water.

  • It’s hydrophilic and readily soluble. It can also be absorbed through the skin.

  • Vitamin C inhibits pro-inflammatory cytokines, so you will sometimes see it in creams and patches to treat conditions like acne.

  • It is unstable and degrades rapidly on exposure to light.

  • Vitamin C has some downsides in topical application: it can discolor the skin (the effective molecule (LAA)is transparent, but it breaks down rapidly to DHAA, which is ineffective and yellowish, and it can cause skin dryness.

  • The dose makes the poison: taking over 100 times the recommended daily dose causes cellular apoptosis and is toxic. It’s really, really hard to take that much Vitamin C.

That mostly sounds great, doesn’t it? It is an essential vitamin, it’s good for you, and it has a really good safety profile. It’s easy to get the required dosage from a healthy balanced diet, so, honestly, taking megadoses does nothing, no harm and no advantage, and only, as they say, helps you make more expensive pee.

But you know what’s totally pointless? This new product of selling people Vitamin shower filters. You attach it to your shower head, and then get an extremely dilute solution of Vitamin C topically applied, most of which then runs off into your sewer. If the dose makes the poison, it’s also the case that you need a minimally effective dose to get the benefit, and this mainly looks like a new way to get money to bleed out of your wallet. Have an orange, eat some strawberries or broccoli, all far more effective at getting the vitamins you need.

If you want to remove chlorine, these filters simply can’t do the job — you’d have to reduce the flow rate to a trickle, optimistically. They’re a scam. They take a little bit of truth and amplify it non-quantitatively and with no empirical analysis, and try to sell it to you with phony promises. Don’t fall for it. If you have a condition that would benefit from topical Vitamin C, see a dermatologist.


  1. lotharloo says

    It looks like it makes a great Christmas gift for the silly family members who are into Homeopathy.

  2. woozy says

    From what I read of the reviews and questions it’s mainly being marketed as a dechlorinization device. A few reviews say it works but all say it’s very expensive or need frequent changing or work for maybe one liter’s worth of shower water or something.

  3. nomdeplume says

    Part of the human race seems to spend an inordinate amount of time thinking up scams to defraud the other part. A pity all that energy can’t be put into a search for real achievement.

  4. chrislawson says

    There is one other downside to vitamin C — as kidneys do their best to clear out the excess in urine, vit C will sometimes crystallise and make kidney stones. Fortunately you have to try really hard to achieve this: the only cases I ever saw reported were back when intravenous vit C was at its faddish peak.

  5. Matrim says

    @4, woozy

    work for maybe one liter’s worth of shower water or something.

    A filter that works for about 8 seconds…sounds legit.

  6. nomadiq says

    Ascorbic acid is also effective at precipitating elemental copper powder out of copper sulphate solution and for that matter, elemental silver powder out of silver nitrate. If your water was contaminated with a high enough concentration of silver nitrate these filters could turn a profit for you.

  7. Holms says

    Eating an orange is sort of like a topical application of vitamin C, except you are rubbing it on the skin’s underside.

  8. says

    Sad thing is, even their list of “nice” facts may be wrong. The guy that originally proposed the idea that anti-oxidants could help you… suggested it as a hypothesis, which a certain nut case ran with. The problem is, since then, he has done more research, which says, “Its unknown what the long term effects of having no anti-oxidants at all, including the ones your own body produces, would be. It could be more cellular damage and cancer, but… oddly, at least in short lived animals, which are unlikely to live long enough to develop those sorts of things, disabling an animals production of them by their own bodies, and denying them in their diet, made them live 25% longer.”

    Then there is the problem of taking “any” extra anti-oxidants when you already have cancer. I suppose its an unknown cause, but this seems to make cancer worse. My own hypothesis on this is that cancer, kind of by definition, is an out of control growth, which is bound to produce both a) a lot of byproducts of oxidation, and b) a lot of extra oxidation damage to the cancer cells themselves, so reducing oxidation would 1) reduce the chemical signature your body might otherwise detect, indicating cells that are under high stress/damaged, and need to be destroyed, and/or 2) actually prevent apoptosis that would naturally occur even in some cancer cells, if the right DNA was damaged, and it became non-functional, not just out of control.

    In the end, the only “truthful” thing that can be said about “any” anti-oxidant, and the biggest lie they make in their claims, is, “We don’t actually know what a safe level is, because its been illegal for decades for the FDA to mandate research on it, but the same iffy, possibly outright fraudulent, studies are trotted out as evidence of their benefits, and safety, despite the fact that we are now starting to see other studies, like the ones dealing with taking, specifically, vitamin C (it being one of the most common of the suppliments) and cancer, which utterly contradict the prior, “The industry that sell it may have faked a study on it, which showed it is a good thing to take, even if you are not deficient in it.”, studies.

    And… its never a good thing when all the positive results are coming from people who are “paid” to come up with positive results, and far worse than that when the law actually undermines necessary corroboration by third parties (or negation by them).

  9. woozy says

    @4, woozy

    work for maybe one liter’s worth of shower water or something.

    A filter that works for about 8 seconds…sounds legit.

    “or something”

    I have no idea of efficiency of vitamin C as chlorine filter. Apparently in theory it can and does work and, although I’m skeptical one reviewer claims to “have had it tested”. However most of the other reviewers claim either it conks out immediately, or needs replacements impractically often, or that it simply doesn’t work.

    PZ goes to great length and convincingly about the lack of health benefits but about the efficiency of a chlorine filter … I have no idea. I’m very skeptical. I suspect it is possible to have it successfully pass a test on a “trickle” of water, but…. I don’t know. (Then again my local water district has, I believe, extremely low on national average levels of chlorine in the first place….)

  10. says

    When some immune system cells are activated they produce super oxide iron. I wouldn’t be surprised if antioxidants counteract that response when you need it to fight cancer.