Common cold treatments – what works, what is just plain nonsense

common cold treatments

It’s that time of year when dozens of common cold treatments are all over the place. On TV advertisements. On displays in your pharmacy. Once again, it’s time to take a look at these lotions and potions to determine which work and which are complete pseudoscientific nonsense.

There are literally a dozen or more homeopathic, herbal, and other unproven concoctions to prevent or treat the common cold, caused by rhinovirus. These common cold treatments are a significant part of the estimated global US$278 billion supplement and nutraceutical industry.

These alternative medicine – so named because there is no scientific evidence supporting their efficacy, let alone safety – products make claims that are so wonderful, many people take them. Then they themselves tell their friends how fast they got rid of their cold. Or that their cold wasn’t as bad after taking the supplement.

Essentially, the whole industry is mostly based on anecdotes, untested claims and the placebo effect. Colds are self-limiting infections, meaning an infection generally lasts some random amount of time, with most people recovering within 7-10 days.

We’re going to review some of the most well-known common cold treatments (there isn’t enough time to review them all), along with what real science says about them in high quality systematic reviews in peer-reviewed, high impact medical journals. This article will review all of the common cold treatments that seem to be out there. Spoiler alert – most don’t work.

One major problem is that the determination of the length and severity of the course of the common cold is entirely subjective. Since the disease is rather mild with few serious complications, it’s hard to determine when it exactly stopped and started, and how bad it was. So, positive results, if they exist, should be treated with a high degree of skepticism. Continue reading “Common cold treatments – what works, what is just plain nonsense”

Supplements to treat the common cold–myth vs science

cold-cureIt’s getting colder outside, and if you go into any pharmacy, grocery store, chemist, or superstore, you will find literally a dozen or more homeopathic, herbal, or other unproven lotions and potions to prevent or treat the common cold, or rhinovirus. These supplements are a significant part of the annual US$108 billion dollar supplement/nutraceutical industry. 

These alternative medicine (so named because there is no scientific evidence supporting their efficacy, let alone safety) products make claims that are so wonderful, many people take them. Then they themselves tell their friends how fast they got rid of their cold. Or that their cold wasn’t as bad after taking the supplement.

The problem is that determine the length and severity of the course of the common cold is entirely subjective. Since the disease is rather mild with few serious complications, it’s hard to determine when it exactly stopped and started, and how bad it was.  The common cold tends to resolve itself without external help, but there really isn’t much you can do to make your immune system attack that cold faster.

 

Continue reading “Supplements to treat the common cold–myth vs science”

Echinacea and the common cold–Myth vs. Science

It’s getting close to winter once again, so people always recommend their various lotions and potions to either prevent the common cold or, at least, to reduce the course of the disease. Alternative medicine’s favorite disease to treat is the common cold, mainly because it’s an easy disease to handle without too many serious problems. Also, from the patient’s perspective, the length and seriousness of the cold is usually very subjective, since the patient has a difficult time making an accurate determination when the cold started or ended, and making a quantitative assessment of the seriousness of the disease. Moreover,  confirmation bias is usually the reason one hears that something worked for the cold–the person who reports some product works forgets all the times it doesn’t. Or completely misjudges the actual effects of any treatment.

The list of products that you might run across in your local pharmacy that claim to have an effect on the common cold are many. Zinc, oscillococcinum, garlic, and vitamin C. I wrote about these products last winter, and they mostly don’t work. The strangest cold remedy you might find is oscillococcinum, which is a homeopathic preparation derived from duck liver and heart, diluted to 200C, or 200 1:100 dilutions.  In other words, in a liter of water there are precisely no molecules of duck guts. And there isn’t any logical explanation of a possible mechanism that would allow one to conclude that duck offal has an effect on cold viruses. Though Oscillococcinum is supposed to be used for flus, many use it for colds, but it doesn’t matter, why would a diluted potion of duck guts cure any virus? Well, Cochrane Reviews concluded that ”current evidence does not support a preventative effect of Oscillococcinum-like homeopathic medicines in influenza and influenza-like syndromes.Continue reading “Echinacea and the common cold–Myth vs. Science”

How pseudoscience makes its case-Part 2. Revised and repost.

Recently, we discussed how science works. It’s not a belief. It’s not a random set of rules. It is a rational and logical process to determine cause and effect in the natural world. Pseudoscience, by its very nature, ignores the scientific process; instead, it claims to come to conclusions through science, usually by using scientific sounding words, but actually avoids the scientific process.  They tend to use logical fallacies to make their case.  Just to be clear, logical fallacy is essentially an error of reasoning. When a pseudoscientist  makes a claim, or attempts to persuade the public of this claim, and it is based on a bad piece of reasoning, they commit a fallacy. Continue reading “How pseudoscience makes its case-Part 2. Revised and repost.”

Preventing and treating the common cold

It’s cold season, so everyone tries various lotions and potions to either prevent the common cold or, at least, to reduce the course of the disease.  Alternative medicine’s favorite disease to treat is the common cold, mainly because it’s an easy disease with not too many consequences.  Also, it’s very subjective, since the patient has a difficult time making an accurate determination of the length and severity of the attack.  Confirmation bias is usually the reason one hears that something works for the cold.  They forget all the times it doesn’t.  Or completely misjudge the actual effects of any treatment. Continue reading “Preventing and treating the common cold”

How pseudoscience makes its case. Part 4.

This is my continuing multi-part discussion about how pseudoscience uses logical fallacies, strawman arguments, and other rhetoric to make its case, rather than real science.  Just click on the links to read Part 1, Part 2, and Part 3.

The other day I engaged in a discussion with a well-meaning pharmacist who claimed that vitamin C could treat colds and prevent other diseases like  “cancer” (I always get annoyed  by people who lump all cancers together, when there are over 200 different cancers, all of which have different histologies, genetics, and causes).  Of course, there are a number of well-controlled clinical trials that show that vitamin C has no effect on the common cold and has no effect on cancers so far studied (see this, this, this and this).

During our discussion, she said “science should be neutral,” with the implication that I wasn’t neutral.  I happen to agree, science should be neutral and it should balanced.  But science should be based upon the scientific method not rhetoric and not using science-y words, at which the writers of Star Trek were well-versed.

So, when I say that I am (or any evidence-based real scientist), “scientifically neutral”, that means I’m willing to weigh the evidence and publications on real scientific issues.  I am not a geologist nor a paleontologist, but I was studying biochemistry when the earliest theories on what caused the Cretaceous-Tertiary extinction event 65.5 million years ago, where all the dinosaurs (well, not all, since technically modern birds are surviving dinosaurs from a cladistic point of view) and some 75% of all extant genera died out or were killed.  In 1980, Luis Alvarez, a brilliant theoretical physicist whose career was extraordinary, along with his son, Walter Alvarez (a geologist), and Frank Asaro, published an article that describe a sedimentary layer across the world that included a rare element, iridium, usually found in extraterrestrial objects like meteors and comets.  The layer fell right at the geological boundary layer that defines the extinction event, so they proposed that the dinosaurs were wiped out by a huge comet or asteroid.

Today, this accepted as a scientific theory with tons of confirming evidence (although some scientists aren’t fully convinced, though they still propose some natural event).  But at the time, it was ridiculed, and scientific meetings were quite energetic in discussions.  The point is that the impact theory displaced the prevailing scientific theory of the extinction event (well, there were several).  One theory replaced another not by rhetoric or appeals to antiquity (that one theory was around forever) or anything else.  In fact, one scientific hypothesis was replaced by another and eventually developed into a solid theory.

We should be neutral in science, reviewing the evidence, then coming to conclusions.  The Alvarez father-son team provided that, and eventually there was overwhelming evidence with the finding and dating of the Chicxulub impact crater in the Yucatan Peninsula of Mexico.

Using scientific neutrality, vitamin C doesn’t work, not because I have an opinion, but because there is no science supporting its efficacy.  There are some articles that support its use in preventing or treating colds, or megadoses for curing cancer, but those articles are in low-impact (meaning obscure) journals or with poorly designed, or non-blinded trials.  My friendly neighborhood pharmacist was stating that I should be neutral between real science and well, nothing at all.  That’s not balance, that’s a close-mindedness to science and the scientific method.  That’s using opinion as the balance to scientific knowledge.  The only thing that should balance scientific knowledge is more scientific knowledge.

Don’t fall for the trap that you should be “open-minded” or neutral to anti-science or pseudoscience.  Open-mindedness and neutrality are expectations that you will balance real scientific evidence, not treat the rhetoric as if it has equal weight to scientific method.

How pseudoscience makes its case. Part 2.

Recently, I discussed how science works. It’s not a belief. It’s not a random set of rules. It is a rational and logical process to determine cause and effect in the natural world. Pseudoscience, by its very nature, ignores the scientific process; instead, it claims to come to conclusions through science, usually by using scientific sounding words, but actually avoids the scientific process.  They tend to use logical fallacies to make their case.  Just to be clear, logical fallacy is essentially an error of reasoning. When a pseudoscientist  makes a claim, or attempts to persuade the public of this claim, and it is based on a bad piece of reasoning, they commit a fallacy.

There are several types of logical fallacies that they employ.  My favorites are Appeals to Antiquity, or old ideas are somehow better than new ideas; Appeals to Authority, or someone who should know better supports the claim even if everyone else does not; Appeals to Popularity, or everyone does it, so it must be useful; and the Genetic Fallacy, where the source is more matter than the merits of the evidence.  Logical fallacies are so prevalent in skeptical community, there are websites devoted to describing them.

The typical pseudoscientist will use logical fallacies to state very definitively that “it’s proven.” It’s the same whether it’s creationism (the belief that some magical being created the world some small number of years ago), alternative medicine (homeopathy, which is nothing but water, has magical properties to cure everything from cancer to male pattern baldness), or vaccine denialists (I’ve discussed this topic before, no need to belabor).  The worst problem is that in the world of the internet, if you google these beliefs, the number of websites and hits that seem to state that they are THE TRUTH overwhelm those that are more skeptical or critical.

So how can you tell the difference between science and pseudoscience in medicine? In medicine, we gather and analyze evidence in one of two ways.

Almost any medical product, device, drug or procedure must, by law, must studied in a Randomized Controlled Trial, which is sometimes called a clinical trial. Essentially, it is a scientific experiment, designed to test the hypothesis of whether the safety and efficacy of a particular medical product is better than a placebo. That is, does the medical product produce results better than doing nothing at all. This is the “gold standard” of investigation, and if the study does confirm the hypothesis, you can be assured it has a benefit to your life (although the degree may be subject to argument). Alternative medicine just doesn’t do this (most of their reasoning is that their beliefs just doesn’t fit into the clinical trial model), so their is no proof that their products work. A clinical trial usually has thousands of participants, and is done in a manner that the patient and the physician do not know who is and who is not receiving the treatment. The results are analyzed statistically and published in peer-reviewed journals. Furthermore, the results are reviewed and investigated by the FDA (and legal bodies in other countries), before a drug or device can be used by a physician. This is an expensive and time-consuming process, in which alternative medicine hardly ever participates.

Now it’s not ethical to test every medical hypothesis with a clinical trial. For example, we know that smoking is bad for your health. Yet, tobacco manufacturers love to insist that there has never been a clinical trial that makes this conclusion. The reason that is true is that it would be unethical to give one group of adults cigarettes for 20 years and another group nothing to see if one would die at a higher rate. So we use epidemiological studies to determine if we can see in a population whether a cause has an effect. We can review records of thousands of smokers to see what the effect will be. Once again, pushers of alternative medicine therapies have not published a study of all the patients who might have used their therapy and see the result. Epidemiology is a scientific process that is critical to preventative medicine–without it, we cannot know if some behavior or public health issue has a causal effect on health.

Remember, anecdotes (“my mother’s friend’s cousin’s daughter was cured by eating this leaf”) are not reasons to accept alternative medicine. Even anecdotes that try to sound like science (“90 out of 100 people think this leaf does work”) aren’t a reason to “believe” in a pseudoscience.

You might have heard that taking lots of Vitamin C helps prevent colds. It doesn’t. And that conclusions is supported by large clinical trials, so unless you are afflicted by scurvy, there’s no reason to take large doses of the vitamin. And that’s the difference between real science and pseudoscience.