#aFactADay2024 #1461: the FINALE part 1! see the master post or the Neocities landing page. the following post is best read on the Neocities website.
Musings from someone new to the concept of long hair
In numerous distinct but overlapping experiments, data was recorded on time spent brushing hair and washing hair, and other miscellaneous occurrences like compliments. These were cross-referenced and regressions were calculated to numerically evaluate various pros and cons of using conditioner on my hair, and thus evaluated all these pros and cons to find that it is not "worth it" to use conditioner as an additional product in my hair.
I've been growing my hair out for around two and a half years now. It was short before, and it's long now. I only cut it once in that period, just a short amount this July to treat some split ends (it did not help). However, this is all a relatively new thing to me, and I've been using a very similar haircare routine before and after: a bog-standard 172-in-1 shampoo, and nothing else. In April 2024, as it was reaching a certain length, I considered that perhaps I ought to take more specific care of my hair now that it was a bit more conspicuous and lengthy. I wrote a small report to mathematically estimating the optimum frequency for using conditioner, optimising for quality per time invested (as there comes a point of diminishing return, surely). It concluded that, with the given information, that optimum frequency was zero - but I decided that I had factored in too few factors and a more in-depth analysis would be required.
Before we go on, here's some not-very-factual facts on hair conditioner. This is "A Fact A Day", after all. The Handbook of Cosmetic Science chapter 67 states that the primary purpose of hair conditioner is to reduce the friction when you brush/comb it. This is achieved by a long hydrocarbon that deposits on the hair to lubricate it. Beyond that, everything henceon is either poorly backed up or out of reach of my understanding.
Hair consists of a cortex and then 8-10 layers of keratinous cuticle cells that give it its most perceptible properties, such as shine and combability. When the hair is wet, these are at their most fragile and their most resistant, so they receive the most damage. Cells can get torn away, peeled up or chipped, contributing to high friction and thus further damage or lots of time needed to brush it. Here are two SEMs (scanning electron micrograph) of hairs that've been brushed 700 times while wet - guess which had conditioner on.
The core tenet of conditioner is that it reduces friction, particularly when wet, and this has knock-on effects that reduce damage to the hair (particularly important with long hair because the stuff at the end is virtually three years old) like split ends and so on. It gets a lot more complicated...
The following section on how conditioner purpotedly works is pretty much just a passage from Wikipedia that's riddled with "citation needed". I found some sources that back it up and some that don't, but it all sounds a bit dubious and a bit confusing either way. The hair follicle, where keratinous cells form, has a layer rich in cisteine groups that are mildly acidic. This deprotonates (loses protons, leaving it a negative charge) when you wash it, which attracts positive quaternary ammonia by standard "opposites attract" rule. These have long hydrocarbon chains pointing in all sorts of directions, helping to patch over sub-cellular chips and smoothing out the surface of the hair. Apparently it also means the hairs repel one another, reducing clumping, and reduce static buildup, reducing frizzing - but that all seems poorly backed up.
If you ask me, there's a lot of truth to what's been said, but when it comes down to it, it's mostly a cultural ploy - something something beauty standards, cosmetics industry, you know the usual sceptic leftist waffle. But to be honest, if you lean into that too far then you just shave your hair off because it's easiest. If I want to present myself as someone with long hair, I may as well present myself as someone with smooth long hair. Well, we'll get into that in a minute actually.
Before we go on, I'll just define specifically what I mean by a couple of terms: "short-term" is specifically about a day, "medium-term" is between a day and a week and "long-term" is, well, long-term. These periods do overlap and are used with vagueness, but these are the ballparks we're working with. Gotta be in the same "Language Game", as I once read in a letter.
A log of when I washed my hair, when I conditioned my hair, and when I received compliments was made beginning in April 2024, shortly after the initialising report. I asked a friend to specifically increase the rate of compliments (proportionally, so as not to skew any daya), although this had limited success, as more compliments were obtained from others than from this friend. Each datum was simply a date; a time of day (morning/afternoon/etc) was also collected but not used. Where applicable, notes were collected: whom a compliment was from, how long it took to condition my hair, and similar.
Shampoo was used on a regular basis, almost always the same shampoo. Two different conditioner brands were used - one consistently up to roughly October and then a different one for the last couple of months (although no difference between the two was noticed, remarked upon anecdotally, or measured). The assumption when I condition my hair is that I've immediately just washed it with shampoo, and that was always the case in the logs, with the sole exception of once when I washed it with a bar of soap then conditioned it (this had no discernible change).
During the period of study leave in May-June 2024 for exams, a special intensive experiment was carried out. For 52 days between 2024-05-10 and the end of June, every time I brushed my hair was recorded, with a timestamp, a duration, stroke-number (how many brushes to brush the hair) and a note (eg, "just had a shower" or "tying my hair up rn", although these are obviously conformed to a finite list of options). It is to be considered that the fact of having to fill out a spreadsheet every time I brushed my hair may have disincentivised me from brushing my hair at some times, and thus the data seen through an absolute lens may not be properly representative. Anyhoosles.
Other factors that were more trivial to numerically evaluate included financial cost of conditioning and how long it takes to condition (time cost).
Beginning with the easiest to put a finger on, how long does it take to condition my hair? 300 seconds (to one sig.fig.). Five minutes. This includes everything that would be done (Standard deviation = 90 seconds: so pretty widely distributed; that is to say that it often takes a lot less or a lot more.) This didn't seem to vary significantly with frequency (i.e. conditioning one day didn't ease conditioning on another ay shortly thereafter) to a measurable degree; the greater effects lie in how much I can be bothered to focus on what I'm doing. For future reference, the minimum time it took was 180 seconds (2 sig.fig.s).
Secondly, let's evaluate the "aesthetic" benefit of conditioner. 15 compliments over the 8-month period were received. Compliments were cross-referenced with how long it'd been since I last conditioned my hair, and surprisingly the results show very little correlation. The mean time since the last condition on days where I received a compliments was greater than the mean time since the last condition on all days. That is to say, although the correlation was weak, it was negative. In other words, conditioning appears to make my hair uglier. This is a surprising result, but it did feel anecdotally as if most of the compliments I received occurred during the longer periods of no-conditioner. We can say that the effects of conditioner are small enough to be ignored after a certain point, and thus all "time since the last condition" values can be capped at that point (which is actually what I initially did) but no matter how you cut the mustard, the same answer is given. My hair looks better when it's less smooth. Or, it would actually be more precise to say that my hair elicits fewer compliments when it hasn't been conditioned in a while.
To grapple with the host of data collected during study leave, brushing data were split into "wet brushes" (after a shower, hairwash, rinse, etc) and "dry brushes" (all others). From the information gleaned in the introduction, we can expect wet brushes to yield the most distinction when conditioner is used.
However, this shows no immediately clear regression. There is one visible pattern, however: that the brushing immediately after using conditioner was invariably lower than the average. It seems to trend upwards for a few days before becoming more random than helpful. Capping it at a certain point as we did previously finally lets us put a number on this: if we cap at 5 days, we get a statistically significant least-squares linear regression! This has a gradient of 2, i.e. every day after a condition takes two seconds longer to brush than the previous, up to 5 days. The real case is likely more complicated than this linear model (it was originally modelled exponentially in the April report), but that matters little: based on this model, the maximum time that a hairbrush could save is 30 seconds spread over five days. Half a minute - a tenth of the average time taken to actually condition the hair, and a sixth of the best-case time.
The first plot immediately above shows the dry-brushes counterpart to the previously-discussed plot. No statistically significant regression, however we cut the mustard, is elicited. Basically, conditioner doesn't make it easier to brush my hair when it's dry. The second plot immediately above shows the time spent total per day brushing; this is quite a different measure, as some days I brushed my hair just once and some days five or more times. Since the time taken to brush once is independent of time since last condition, and the number of times that I brush my hair in a day is usually related to what sort of thing I'm doing and thus is also unrelated, we'd expect no pattern at all. That's what I first saw in the data, but there is apparently a statistically significant negative regression. That is to say, according to the data collected over these two months, using conditioner more frequently seems to decrease the quality of the hair, meaning it takes longer to brush. This is likely an anomaly caused by an underlying bias or similar (even though the R-value is statistically significant, p<0.05), but it does rather significantly quash any idea that investing time into conditioner pays off in the long run.
The two benefits of using conditioner that I thought would exist (aesthetic and mid-term time-savings) turned out to be less than negligible. This is a rather conclusive answer that, no, it is not worth it to condition, by quite a significant margin. However, I collected all this data so I may as well flex about it a little.
Beginning with the easier factors, the financial cost of conditioner was surprisingly low. I have quite a lot of hair (it's thick and long) but I usually used around a teaspoon, occasionally more. The stuff I buy in the quantity I buy it in only costs 9 pence per teaspoon - working at UK minimum wage, that's equivalent to about 28 seconds' work.
Niceness to the touch, fondlability, and similar texture-related factors are difficult to quantify, but from anecdotal evidence this does improve in the short-term with conditioner, but not in the medium-term, as is evidenced by the very weak correlation with brushability discussed. Either way, this effect is so relatively small in comparison to the large time-cost.
Seeing as I have about 200-odd data just lying around, I may as well give you a couple of graphs.
Brushes labelled with "after shower" are the "wet brushes" - this includes after just a hair wash or a bath or whatever. The blue section was the largest "reason" for brushing my hair as this happened guaranteed every single day - the first hairbrush of the day, having just spent eight hours in bed messing it up on my pillow. Before and after tying it up were also common reasons enough to elicit their own segments, and everything else falls into the "top-up" category, which encompasses all the little bits and bobs that accumulate over the span of a day and get annoying by the end.
It may have seemed arbitrary to split brushes by "wet" and "dry", but these two types of "brushing events" have very distinct patterns, as shown in this scatter plot between the number of strokes and the time spent:
Wet brushes weren't inherently slower - there is some overlap between these two clouds, although their centres of mass are very different. You can easily guess which cluster corresponds to the dry brushes. These took on average 21 seconds and their regression has a 1.2s gradient (corresponding to roughly 1.2 seconds per stroke) and a very small intercept of 2s (probably corresponding to moving the hair brush between hands, and tiny little things like that which are constant every time). The wet-brushes cloud had an average duration of 81 seconds and a gradient of 0.64 seconds, meaning each stroke was on average twice as quick when my hair was wet. This seems at first counterintuitive (why are strokes quicker when the hair is trickier to brush?) but instead points towards a significant change in technique when brushing wet hair. This technique (anecdotally speaking) is slightly more energetic, involving lots of short brushes towards the ends of the hairs. There was also a significantly greater offset (~26s), which points towards a constant number of strokes that have a different rate. In other terms, the technique used for dry hair was also used on wet hair, after using this "quick" technique. This is somewhat logical if we look at the graph, and see that following the trend line down, it takes a corner at around 25 strokes, where it changes from the wet-brush gradient to the dry-brush gradient. I sound like a painter.
Since these data point to a more vigorous technique to a non-negligible degree which clearly affects multiple factors, there's an argument to be made that this is the fact that's worth targeting. To improve and optimise everything about my mop, perhaps I ought to focus on how I brush after a shower. As per the introduction, the hair is most fragile yet most resistive when wet, thus must vulnerable. Conditioner does indeed have a medium-term effect on the smoothness of the hair, which is reflected in how long it takes to brush it (as per the previous graphs) but will also reduce damage to the hair. The effect was small in the medium term (not enough to incentivise based on time or aesthetics), lasting around five days, but slightly more marked in the short-term, as is shown in the graph below. The red datapoints are immediately after using conditioner (short-term), and the darker blue points are in the medium-term, specifically 1-4 days (chosen as the period over which conditioner was shown to have a trailing effect).
As can be seen here, the short-term effect of conditioner is much greater than the medium-term effect (even though the products claim to be longer-lasting than is observed here, and a longer-lasting effect is agreed upon by cosmeticians). This is a slightly different story now that we're working to solve a different problem: no longer are we worrying about "is conditioner worth it" in the medium-term (as the title of this article should have read) but rather minimising damage to the hair.
What should be done to minimise damage to the hair in the long-term needs to be investigated in more depth. Conditioner helps in the short-term but less so in the medium-term, although this effect is yet to be conclusively evidenced. The greater question is, how much does this really matter? How much will this aid the health of my hair (e.g. preventing split ends) and thus improve the joy in my life? This is a question that requires a much greater experiment, somehow exceeding the 8-months of this one. It's a very difficult thing to plan, having just one head of hair and no proper control over so many factors, to the point where I'd hazard to say that it's impossible to do this larger-scale investigation. It's with a heavy heart that I end this discussion with almost exactly the same sentiment with which I ended my report all the way back in April: no, but maybe even more science will help!
While I have your attention, if anyone has any idea what to do with all the data that I have, please let me know! I'm sure there's more science to be done on it all, or if you think that there could be some fun other statistic to collect over time, just let me know - I'm sure I'm game! My hair log was unfortunately one I'm planning on stopping in the new year, to focus on other logs, especially because it was started to run this experiment which will reach its conclusion in about 26 words. If you have any ideas or thoughts whatsoever regarding the data or statistics mentioned in this article (or any other!), I'd love to hear them!
To answer a more specific version of the question in the title, no, conditioner is not worth it in the medium-term. This article exposed lots of interesting trends, as well as fun facts about conditioner. (Is that not what this is about, ultimately?) One of the more interesting revelations was the notable ramifications of the different technique used to brush wet hair. The information given in the introduction hints at a major long-term effect (speaking in terms of years!) of this technique, which is more energetic and possibly destructive, but the scale of which is unknown. The effect of conditioner on this is also not known and unestimatable. The only answer to this question that can be given is, we need more data! (As is always the way.) Moving forwards, the number one focus has shifted off conditioner as a product and onto hairbrushing.
I'd love to hear your thoughts on what I can do with all this data that I don't feel has been used to its full extent herein. I'd also love to hear your thoughts on this article in general, or the "fact-of-the-day finale" series, a component of which it forms.
