I honour of my 2nd cold in less than a month, I figured I should review some common cold/flu remedies!
1st we have Vitamin C.
Vitamin C has been propagated as a cold remedy by Alternative Medicine components for some time. A quick stroll through any pharmacies will also reveal an alarming push by the pharmaceutical industry/professionals for this product as well. The most common claim I have encountered is that Vitamin C will “boost your immune system” and “shorten the length and severity of the common cold” (It should be noted here that the “common cold” is not one virus or even one particular strain of viruses, instead it is a catch all phase used to describe a mild viral upper respiratory tract infection).
“Shortens the length/severity of the common cold”…
Strange…
I was never told about this in my training! I wonder why!? You would think that if Vitamin C worked so well on the common cold (the common cold is one of the most often seen/frequently occurring medical complaints, accounting for a large amount of doctor’s office + Emerg Department visits), that I would have been made aware of it’s effectiveness in my training/education. Must be some Big Pharma conspiracy to suppress the truth about the effectiveness of herbal remedies (ignoring the fact that Big Pharma owns most of the herb/supplement companies)! Well…not exactly. The truth is that Vitamin C is simply not an effective treatment modality for the common cold.
A review of the literature reveals that Vitamin C has no therapeutic benefit in the treatment of the common cold. To quote the Cochrane Review, “30 trials involving 11,350 participants suggest that regular ingestion of vitamin C has no effect on common cold incidence in the ordinary population. It reduced the duration and severity of common cold symptoms slightly, although the magnitude of the effect was so small its clinical usefulness is doubtful”. Depending on which study you look at, the effectiveness of Vitamin C ranges from: No effect to potentially decreasing cold symptoms by approximately several hours.
So best case scenario, consuming Vitamin C can decrease the length of your cold symptoms by several hours. Taking into consideration that most colds last 7-10 days; a reduction of only several hours in the length of cold symptoms is not all that impressive, especially for a product that is advertised as preventing/fighting off the flu. It should also be noted that the studies that do identify Vitamin C as potentially capable of decreasing cold symptoms (again, best case scenario, by several hours), state that this evidence could be statistical noise/the result of subjective reporting. There is some soft prelimary evidence that seems to demonstrate the beneficial use of prophylactic Vitamin C (to prevent the onset of the common cold), but the evidence currently available is far from conclusive.
For a more thorough review of the current medical literature pertaining to the efficacy of Vitamin C in the treatment of the common cold, please have a listen to Dr. Mark Crislip’s Quackcast (Dr. Crislip is an infectious disease physician who makes a living battling bacteria, viruses and other microscopic bad guys)
http://www.quackcast.com/page2/page2.html (Quack Cast # 28)
Secondly we have Echinacea.
As with Vitamin C, Echinacea is propagated by Alternative Medicine proponents, as a means of fighting the common cold. The most common claim that I have heard is that ingesting Echinacea helps to decrease the length and severity of cold symptoms. Hmmm…Sounds like a testable claim! Let us have a look at the medical literature shall we!
To quote the Cochrane Review: “Preparations of the plant Echinacea are widely used in some European countries and in North America for common colds. Echinacea preparations available on the market differ greatly as different types (species) and parts (herb, root, or both) of the plant are used, different manufacturing methods (drying, alcoholic extraction, or pressing out the juice from fresh plants) are used, and sometimes also other herbs are added. We reviewed 16 controlled clinical trials investigating the effectiveness of several different Echinacea preparations for preventing and treating common colds. Two trials investigated whether taking Echinacea preparations for 8 to 12 weeks prevents colds but found no clear effect. The majority of trials investigated whether taking Echinacea preparations after the onset of cold symptoms shortens the duration or decreases the severity of symptoms, compared with placebo. It seems that some preparations based on the herb of Echinacea purpurea might be effective for this purpose in adults, while there is no clear evidence that other preparations are effective or that children benefit. Side effects were infrequent but rashes were reported in one trial in children”.
Might be effective!? That is certainly not what I have seen plastered all over Echinacea bottles at my local pharmacy! According to the individuals pushing this stuff…IT WORKS…PERIOD! Strange, you would think that the clinical trials would demonstrate a positive effect, if Echinacea actually worked as well as it is marketed to work. Further review in the literature reveals that, similar to Vitamin C, use of Echinacea may have a mild therapeutic effect, again decreasing your cold symptoms by only several hours (and again, this effect could simply be the result of statistical noise and/or subjective reporting). As pointed out with Vitamin C, for a product that is supposed to prevent/fight off a cold, decreasing your symptoms by a few hours over the course of a 7-10 day cold is not all that impressive (again, best case scenario it does this, worst case scenario it does nothing).
It should be noted at this point that there was a recent Lancet (one of the best peer reviewed medical journals) indicating that Echinacea is effective for treatment of the comment cold. I must admit that I was rather surprised when I came across this article. However, review of the Lancet article proves that even the Lancet can get it wrong. For a more thorough review of the Lancet article, please read Dr. Steven Novella’s (Dr. Novella is a clinical neurologist and host of the Skeptic’s Guide to the Universe) blog on the subject (he does a better job on dissecting the Lancet article that I could ever hope to):
Steve’s blog: http://www.theness.com/neurologicablog/?p=641
For additional information + a review of the current medical literature pertaining to Echinacea, please have a listen to the following podcasts (again done by Dr. Mark Crislip)
On Echinacea: http://www.quackcast.com/page2/page2.html (Quack Cast # 18 and # 2)
So when it comes to the common cold, the old adage is true…
You can stay at home, gets lots of rest; drink lots of fluids and be better in 7-10 days
OR
You can head out to the pharmacy spend your hard earned cash on Vitamin C and/or Echinacea and be better in a week to a week and a half
This has been the skeptical samurai…
Working to serve through the process of inquiry
The Skeptical Samurai 