A primary goal of the Beauty Brains is to teach you to recognize marketing hype and nonsense in the beauty business. It is our hope that after being 
part of the Beauty Brains community for a while, you should be able to figure out for yourself what products are worth spending money on and which are complete wastes. You should also be able to filter questionable beauty advice, identify beauty myths, and decide what cosmetics are really safe.
While we’re happy to answer your Beauty Questions, we just don’t have enough time or brain power to get to them all. That’s why we’re going to do a series of posts called Skeptical Beauty 101. (Thanks to the Skeptics Guide to the Universe, Skepchick and Carl Sagan for their inspiration). With this skeptical thinking toolkit, you should be empowered to answer many of your beauty questions yourself.
Beauty Skepticism Series
In this series, we’ll cover the following topics. We will be publishing a new one once a week until we run out of topics. Feel free to suggest other useful topics in the comments section below.
1. The Scientific Method
2. Experimental Design
3. Null Hypothesis
4. Occam’s Razor
5. Anecdotal Evidence
6. Confirmation Bias
7. Correlation & Causation
8. Argument from Authority
9. Extraordinary Claims / Extraordinary Evidence
Beauty and the Scientific Method
The most useful technique for figuring out which beauty products, advertisements, or advice are worthwhile is the Scientific Method.
You probably first heard of the scientific method in grade school and probably think it is something only good for science fair projects. Fortunately, it’s much more useful and can be used to you help get closer to the truth about any subject while filtering out your personal and cultural biases.
It is used every day by doctors, car mechanics, investigators, and even you. When you misplace your cell phone, you use a version of the scientific method to help you find it.
4 Steps of the Scientific Method
The scientific method has four basic steps.
1. Make and observation about the world
2. Generate a hypothesis to explain the observation
3. Make a prediction using the new hypothesis
4. Test (experiment) to see if your hypothesis is correct.
The more experiments your hypothesis correctly predicts, the more likely it is to be true. Of course, the validity of your hypothesis depends greatly on both the quality & reproducibility of your experiments. Which means you need to make every attempt to minimize the amount of error in your experiments. Also, someone else should be able to repeat what you did and get similar results.
Beauty Applications of the Scientific Method
So, how can you apply this to what you know about beauty?
Let’s look at an example.
Step 1 – Observation: You notice acne the day after you eat a chocolate bar.
Step 2 – Hypothesis: “Chocolate bars cause acne.”
Step 3 – Prediction: If you eat chocolate, you will get acne.
Step 4 – Test: Check scientific literature for other experiments that people have done related to chocolate and acne. Create a series of your own tests where you eat chocolate and observe whether you get acne or not.
If you start with no acne, eat a chocolate bar and don’t have a break-out within some amount of time (24 hours?) then you can safely say that your hypothesis is false. Chocolate does not cause your acne.
If however, you do get acne the next day, it does not mean you’ve proven chocolate causes acne. It just means you haven’t proven that it doesn’t cause acne. You’d have to run more tests and continue to get the predicted results before you can confidently make the statement “Chocolate causes acne.”
General Knowledge
Of course, it’s also important to remember that any tests you run on yourself are only applicable to you. They will not necessarily be useful (or true) for anyone else. To figure out what is more generally true, it’s better to look at large, peer reviewed studies. The sheer amount of controlled data they collect is much more reliable than your small experiments. (Although, you’re small experiments may be more predictive of what happens to you).
Limitations of the Scientific Method
While this process can lead you closer to what’s true, it can not ultimately determine whether something is absolutely true. There is always (no matter how remote) a possibility you could run some new experiment proving your hypothesis wrong. There are incredibly few things we know for certain.
Beauty Brains bottom line
People are very good at making observations and creating hypotheses to explain the observations. But if you really want to know whether something you think you know is true, apply the scientific method and find out.
Come up with a hypothesis, make some predictions and test to see whether those predictions come true. Without taking these steps, your hypothesis is no more than a guess. And guesses are usually wrong.
*Incidentally, eating chocolate doesn’t generally cause acne.
Have you used the scientific method to figure out some beauty problem? Leave a comment below and let the Beauty Brains know.
{ 11 comments… read them below or add one }
I imagine subtracting the noise comes in on experimental design — that you have to NOT eat chocolate for a month or so, measure your zits, and then not take that baseline level into account when you make your observation. That’s one of the worst failings of these “jumping to conclusions” sorts of things.
That, and before you test your idea, make sure you know what you’re assuming. It reminds me a bit about the question I asked about why grey hair seems to take dye less well. The thing to ask isn’t just, “Why is that?” but first off, “IS this actually the case?” and then “Why?” Make sure you’re observing things correctly forst off — that comes before ANY experiment, hypothesis, or theory at all.
And make sure you document, so someone else coming up behind you can test it as well — because the more people test things, the more robust the answer will be.
Metaphor for this: You look outside and see a UFO. Step 1 should not be to ask what planet it came from. Step 1 should be to get to the optometrist and sit your ass down in front of an eye chart.
Thanks so much for doing this series. I think it’s a great idea!
What about measurement as a topic? I know it’s a big part of research in my field. How do people measure things like wrinkles and acne? Do most studies use self-report? What kind of objective measurement tools are there?
And while I know that you know this, I think it would be helpful for your readers to clarify that the scientific method is a little more complicated than your example suggests. How do you know what the timeframe is for the chocolate causing the acne – is it 1 day or 1 week? and what if you do get acne the next day – you can’t really know that it’s caused by the chocolate. It might be caused by a lack of sleep, or a really stressful day. As you know, a well-designed study is rare – and being able to prove causality is just about impossible (especially when you can only DISPROVE things with the scientific methods, and never really prove anything).
p.s. sorry if I went overboard. just got back from doing grant reviews.
I love the metaphor Janis!
@QuizziGal – You’re right. We did simplify the system a bit. This is an introductory series and no doubt some things will get glossed over a bit.
Hopefully we will clarify things over the course of the series. Your idea about discussing measurements is a great one and we’ll try to include it in the series.
The hypothesis itself might be completely flawed in any case. It might not be the chocolate that is causing the acne, it might be something that is in the chocolate. Or the chocolate might need some other factor, like say milk or meat. You have to be prepared to not only accept or reject your hypothesis – you might have to completely rethink it.
I’m just pleased that you gave a shoutout to Carl Sagan. The Demon-Haunted World is one of my favorite reads. Unfortunately, I think the understand of science in the U.S. is even worse now than when he died.
A good thing to discuss might be the difference between a theory in layspeak and a theory in the scientific community. It just irks me when people talk about things like evolution as “just a theory” when in science a theory has to have robust evidence supporting it.
I’m starting the process of my own experiment to see whether I can find a (external chemical) trigger for my perioral dermatitis, which I will concede will prove nothing for the general population because even the medical field isn’t able to prove anything for certain.
Looking into the peer reviewed literature on the subject, there are at least two papers written on two isolated cases where a rough cause-and-effect relationship could be drawn between flare-ups of perioral dermatitis and the use of fluoridated toothpaste. In both cases it was a matter of stopping and starting to use the toothpaste over the course of many months, and within a couple of weeks of the change the skin condition would return or disappear.
Neither paper could definitively prove that it was fluoride – these weren’t clinical trials, they were two patients who visited their doctors, and the latter then reported on how their treatments played out. What it does show, at least, is that something happened which is worth investigating.
Is it fluoride? Given its importance in dental care, you’d want to be darn certain before you permanently avoid it. It could very well be something else in the toothpaste that was in one brand but not the other; but if this hypothetical other ingredient is *always* found with conjunction with fluoride, then does it make a difference to what you advise the patient?
Then there’s the fact that there are many other sources of fluoride that have not been eliminated, such as from drinking water and food. They may not have concentrations as high as toothpaste, but they will still be there during the ‘control’ periods.
My apologies if this is rambling, but I hope that this example illustrates the nature of the beast which we face. There has been so much more work done on this topic that I didn’t cover, but I hoped that this example might explain that even with my own hypothesis testing, I would not bet on my results being definitive. And nor should any of you.
Reminds me of how EVERYONE says sugar causes hyperactivity. This was ONE doctors’ observation and the media ran with it. I researched this for a long time and found nothing to prove this.
My kids ate plenty of sugar and never once got hyperactive!
What happens is that kids get excited over the candy/treats, etc…
Anyway, thanks for this one! I really enjoyed it!
buenos dias,
Lynnette
I suggest a definition of the term ‘conventional wisdom’ with a look at how it is popularly used versus what it truly means.
This sounds like a great series. How about a topic on statistics and data presentation? There is no difference between saying “studies show a 100% increase in the occurance of …..” and “studies show there was only an increase for 1 in one million to 2 in one million…..” yet the impression is quite different. And neither say anything if the standard deviation was 5 in one million.
Hi,
The idea of beauty skepticism is great. Congratulations on your series. One suggestion I have is that you identify yourselves and provide us with enough background information about yourselves so we can determine your qualifications.
Also, since you can’t cover all the details in each topic you present, you might consider adding some links to outside sources that do cover the same topics in depth.
Sincerely,
Bob Carroll
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