Change my view - Hyaluronic acid vs Glycerin

Perry

When formulating a skin product, from a performance standpoint, glycerin can do everything that Hyaluronic acid can do but at a much lower cost. 

Are there any scientific studies that would show I am wrong?

*Of course, HA has marketing benefits over glycerin but I want to focus on product performance.  

ifamuj

Hi Perry,

Speaking from an experience point of view, I've found hyaluronic acid to be much less non-greasy and much more skin-hydrating in comparison to glycerin. Hyaluronic acid is a natural component of the skin so it blends in better. I think it all comes back to experience. Sure you can use milk all over your face, but using an AHA product seems more convenient. I'm not sure if it's the right analogy to make here but I hope you get the simple point. People just prefer one over the other based on how the ingredient makes them feel when applied topically. And God knows best. 

ngarayeva001

Although it's expensive to use it like that, high molecular weight HA is a great gel maker. It tolerates high amounts of electrolytes, broad pH range and ingredients that will destroy any acrylic acid based rheology modifier. It's also much more elegant than, say, clear grades of xanthan. I use 0.5% oh high molecular weight HA in most of my serums. For emulsions, I don't see a reason to use it. I am not very fond of glycerin due to its tackiness, but a blend of glycols will do the job for less.

MarkBroussard

There are several grades of HA that vary in molecular weight and ability to penetrate the epidermis and dermis ... it is not a singular molecule as is glycerin.  So, the first distinction is which grade of HA are you comparing glycerin to because you will get different answers with different grades of HA.

HA is the major component of the extracellular matrix, part of the skin's NMF and it performs more than the one function in the body of simply being a humectant which is the only function of glycerin.  So, I think the assumption that glycerin "can do everything that Hyaluronic Acid can do" is a bit off the mark to begin with.  

ngarayeva001

I thought none of them penetrates the epidermis. The smallest HA molecule is around 5,000 Dalton, or I am missing something?

MarkBroussard

Yes, you are missing something.  5,000 Dalton is not the smallest HA molecule and, yes, certain grades of HA can penetrate the epidermis.

Perry

@MarkBroussard - I agree it's part of the NMF and certainly within living cells hyaluronic acid does things that glycerin doesn't do. It's a molecule produced by cells and involved in metabolism.

But when delivered topically from a skin care product, what specifically does Hyaluronic acid do that glycerin doesn't do?  Consider whatever grade would do the most different thing.

smok

Perry said:

@MarkBroussard - I agree it's part of the NMF and certainly within living cells hyaluronic acid does things that glycerin doesn't do. It's a molecule produced by cells and involved in metabolism.

But when delivered topically from a skin care product, what specifically does Hyaluronic acid do that glycerin doesn't do?  Consider whatever grade would do the most different thing.

I agree with you not because I have tried or compared

But when the price of the product exceeds the limit I know that it is about marketing

Like that argan oil

  And Aloe Vera

My father, who was born in 1931 and died in 1999

He knew and told me that ,aloe vera had an effect ,on the skin.

How much is the price of aloe vera today ???

ngarayeva001

The prices of glycerin and HA are determined by the cost of manufacturing not marketing. Glycerin is made by the means of a rather simple chemical reaction. HA is made by the means of bacterial fermentation in most cases, which is obviously more expensive.

ngarayeva001

I wonder what is the smallest MW? I searched again but can't find anything smaller than 4,000.

Perry

@ngarayeva001 - certainly HA costs more to make, but since it is perceived as a premium ingredient by consumers & cosmetic marketers, raw material manufacturers can get a much bigger profit despite the extra costs. So production costs figure in only a little bit.

No raw material maker would want to get into the glycerin making business because glycerin is a commodity with razor thin profit margins. Conversely, lots of raw material makers would get into the HA business because you can make more money. 

MarkBroussard

The higher molecular weight grades of HA will form a film on the surface and reduce TEWL.  Combined with a micro weight HA that penetrates the epidermis and you'll get humectancy + TEWL reduction ... I don't think that is something that glycerin is capable of.  Then, simply compare the amount of moisture that can be absorbed/attraced by HA versus glycerin and you 'll see there is a substantial difference.

Whether topically-applied HA that is absorbed into the epidermis functions in a similar fashion to native HA in the extracellular matrix, I don't see any reason why it would not perform the same functions as native HA.

It's like comparing a Toyota Corolla to a Mazeratti ... they're both cars, but they're not the same.

ngarayeva001

That's a perfect comparison. People buy Mazeratti not because of it's unique properties/speed/whatever but due to what I call competitive consumerism. "Look, I have money for an expensive toy! I am better than average Joe". It's a fancy moisturiser with hyaluronic acid, it's fashionable, it's expensive. It's buying a dream, not the product.
I don't say that glycerin is the way to go, but I think the point Perry is trying to make is that you can achieve the same result with cheaper materials. And I would actually say it's not glycerin on its own but a mix of butylene glycol, sodium lactate, betaine and maybe a drop of glycerin too. Regarding TEWL reduction, I don't think you should rely on HAs film-forming properties for this. There is good old petrolatum and dimethicone for that.

MarkBroussard

ngarayeva001 said:

... but I think the point Perry is trying to make is that you can achieve the same result with cheaper materials. 

The flaw in the logic in that argument is the assumption that glycerin delivers the same results as hyaluronic acid. 

If you are taking a very simplistic definition of "do the same thing"  such as they are both humectants, but you fail to take into account that one is a much more powerful humectant than the other ... then, yes, they "do the same thing", but that by no means implies they are equivalent.

Same with the cars ... yes, a Toyota Corolla can get you from here to there, but it can't go 0 to 60 in 2.3 seconds.

By being limited in the definition of "do the same thing" you are setting up a false equivalence as it ignores relative degrees of performance and the duration of performance.

Perry

Thank you for all the responses. It's at least got me thinking.

@ngarayeva001 - I overlooked the gel possibilities, so congratulations, you've changed my view...a little bit.

I appreciate the car analogy, but that is more of an emotional argument than a scientific one. Also, the way the analogy breaks down is, as you point out, there are measurable things a consumer would notice as different between a Mazeratti and a Corolla.

Beyond feel differences of the raw materials (which can be formulated around) a consumer would not notice any obvious differences between a formula with HA vs Glycerin.

But you have made some claims which could be measured. 

1.  "will form a film and reduce TEWL" - Ideally, to support this you could show a study comparing TEWL readings of Glycerin vs HA.  I found this study which concluded repeated used of a high level of Glycerin does not impact TEWL.
https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1467-2494.2001.00060.x
I searched Google Scholar but couldn't find a study to demonstrate an increase in TEWL using Hyaluronic acid.

2.  "HA that is absorbed into the epidermis functions in a similar fashion to native HA in the extracellular matrix" - What are these functions and how is it different than what glycerin is doing in the epidermis?

3.  "...much more powerful humectant." - Perhaps it's true that it absorbs more water per molecule of HA but then you just increase the amount of glycerin (at a much lower cost) to compensate. There isn't a humectancy rate that you can achieve with HA that you can't achieve with Glycerin.  At least, not that I could find.

I opened this discussion as a "Change my view" so I don't want it to seem like my opinion is unchangeable. It is changeable, but no one has presented any science-based studies to support the use of HA over glycerin as a performance ingredient in a topical skin care product.

MarkBroussard

Perry, I seriously doubt that anyone had conducted a study as such that has been published.  But, let's start with the premise that Glycerin is as equally effective as Hylauronic Acid when applied topically ... where's the evidence to support that premise?

Unless you are a manufacturer of Hyaluronic Acid, I don't know who would dedicate resources to such a comparative study unless someone in academia has looked at it, but I have never seen a study comparing these two ingredients.

Perry

I couldn't find a study specifically comparing Glycerin and Hyaluronic acid but this paper looked at how glycerin, HA and a silicone performed as moisturizers.

http://www.e-ajbc.org/m/journal/view.php?number=640

1.  Glycerin was more moisturizing than HA - "the cream including both glycerin and silicone oil showed the highest moisturizing value and the longest holding time of hydration. The second on the result was the cream containing both hyaluronic acid and silicone oil, followed by the glycerin cream, hyaluronic acid cream and silicone oil cream."

2.  Glycerin was superior for TEWL - "the cream including both glycerin and silicone oil showed the most decreased value of TEWL and the longest holding time. The second on the result was the cream with both hyaluronic acid and silicone oil, followed by the silicone oil cream, the glycerin cream and the hyaluronic acid cream."

Now, this is only one study and I've only seen the abstract, but without evidence to the contrary, I don't know how hold the belief that HA is superior to glycerin.  This study shows glycerin is superior to HA and there are no competing studies to show the opposite. 

A belief in the superiority of HA over glycerin is not supported by science (at least that I could find).

MarkBroussard

Well, here's the issue that makes not specifically clear: 

In the study, you don't know how much Glycerin was used and you don't know how much Hyaluronic Acid was used ... was it a 1:1 comparison? ... we don't know.  If you can get the entire study, it would be interesting to see the composition of the various mixtures they were evaluating as that would provide the proof or evidence that 5% Glycerin + Dimethicone is more moisturizing that 0.5% HA + Dimethicone, for instance.

Perry

I'll keep trying to find the full study but even if that were the case, using 10 times as much Glycerin is still cheaper & more effective than HA which costs at least 60 - 100 times more. 

Glycerin = $2.6 / pound
HA = $177 / pound
(from https://www.makingcosmetics.com/)  Although at the company I worked for we could get glycerin for $0.60 a pound.

MarkBroussard

From a cost standpoint, absolutely.

What I would like to see is if they compared a SLMW or micro HA that penetrates the epidermis which would be a head-to-head comparision.  If they used a higher mw HA, then the results are not particularly surprising, although there is no indication of the degree of difference ... was it 2% better or was it 40% better.  Again, you need the whole study to understand the facts on which you can better draw a conclusion.

But, the complete the analysis, let's now consider the differential in selling price point of a moisturizer that contains HA + Glycerin to one that contains Glycerin only ... 

JonahRay

I've read somewhere about glycerin's impact on the stratum corneum -something to do with the transition of lipid crystalline structures into liquid states as well as increased desmosome degradation (so better tissue sloughing). If I'm to add hyaluronic acid to a formulation - it would typically be for marketing, not for additional hydration benefits.

ngarayeva001

Oh wow! The prices dropped significantly. 1kg of HA on DIY (repackers) market is about $550 now, it was closer to $1000 two years ago.

Pharma

It was even higher (a lot) in the early days of HA, back when it had to be isolated from rooster combs. The marvels of biotechnology!

Dr Catherine Pratt

I love this, maybe the two are also grouped differently i.e. use Glycerin in cosmetic preparations and HA in cosmeceutic preparations. Clients are now asking for a natural cosmeceutical over a natural cosmetic and that is when you suggest HA?? if that makes sense.

The car analogy I think is a good one. I only drive Mercedes now, my kids would not get into anything else LOL I had one when my first child was born and its a running joke that the children only ever have Mercs!

Although, the Rolls Royce engine would outdo the Merc since Rolls Royce is made by 'PRATT & Whitney' Haha!

What does everyone think about the e-cigarettes that are flavoured but using glycerin as the solvent?? I have friends that do this and I thought it would be very heavy to suck glycerin into your lungs? I know it is heated but I thought maybe I could find them a different solvent maybe like Propanediol ?? Any suggestions?

Pharma

Dr Catherine Pratt said:

...

What does everyone think about the e-cigarettes that are flavoured but using glycerin as the solvent?? I have friends that do this and I thought it would be very heavy to suck glycerin into your lungs? I know it is heated but I thought maybe I could find them a different solvent maybe like Propanediol ?? Any suggestions?

Get them a PAX3 and have 'em vape high quality pipe tobacco . That's what I do because it seems the least unhealthy option of all (less chemicals, nearly no tar, and the full kick of nicotine). See, glycerol but also propylene glycol are used more for the "smoke" (vapour) than anything else, it's the same as disco fog. Ethanol often serves as carrier/solvent for nicotine/flavours but in its pure form ain't nice to vape, hence mixtures of water/ethanol/glycerol are employed. The problem is that many vaporizers for liquids heat above 220°C and that's when glycerol and glycols decompose to hazardous aldehydes! The advantage of a 'weed' vape is that good quality pipe tobacco (don't try cigarette tobacco!) doesn't contain humectants (cheaper one does and clogs the vape fairly quickly) and that the PAX3 only heats up to 215°C max. Problem solved. Well, that's if you like pipe tobacco flavour and don't give a darn about nearly no visible smoke/vapour and a session of 5-15 minutes. Cheaper vaporizers with a lower draw resistance work better for 'quick hits' but forfeit flavour quality. 1,3-Propanediol should work because its boiling point is between the lower boiling 1,2-propanediol aka propylene glycol and glycerol. Since it's not a glycol, it may not form aldehydes... but that's mere speculation and I honestly don't know how healthy it is to inhale either of the propanediols. If you wonder why glycerol works with a boiling point of 290°C: It is passively drawn into air by water/ethanol vapour whereas propylene glycol boils at vaporizer temps.

Dr Catherine Pratt

Wow thank you so much I will definitely pass that on. Yes I was thinking of Zemea 1,3 propanediol. I did ask them and one said he was using a pure blueberry glycerin extraction?? Hear of that?

So you are saying there are two systems in the process, but I think they are getting the flavour from the PG?? They are right into mixing up various flavours and one has become so good I asked him to come work with me in perfumery. I also heard them being very chesty when they have a couple of sessions, like more than a cigarette smoker, does that make sense?

Doreen

Perry said:

(...) @ngarayeva001 - I overlooked the gel possibilities, so congratulations, you've changed my view...a little bit. (...)

That's also the biggest reason why I use medium/high molecular weight hyaluronic acid in serums.

It's funny that in private I use it for its viscosity and work-related I only deal with an enzyme that breaks it down (a hyaluronidase) which causes i.a. loss of viscosity of HA. (This increases tissue permeability and has so many pharmaceutical uses from preventing necrosis of skin (when extravasation happens with some chemos) to the possibility to inject higher volumes subcutaneous, as there isn't much space between the dermis and hypodermis).

ngarayeva001

I know hyaluronidase is used to fix result of not very tastefully injected lip/face fillers.

Doreen

@ngarayeva001
Correct! That as well.

Dr Catherine Pratt

So in your work are you using high molecular weight? Or not at all just the catalyst? What is the work you do sounds interesting?

EVchem

@Perry @MarkBroussard - The full study is in Korean, but the tables are in english and  you can see they are using 1:1 ratio. I  can't read Korean so I don't know the MW of the HA.

Tangentially related, are we comparing glycerin to true Hyaluronic Acid? We exclusively buy Sodium hyaluronate. I know there's some kind of equilibrium in solution, just wondering  if companies are really buying as HA.

Perry

@EVchem - Great find, thanks!

smok

EVchem said:

@Perry @MarkBroussard - The full study is in Korean, but the tables are in english and  you can see they are using 1:1 ratio. I  can't read Korean so I don't know the MW of the HA.

Tangentially related, are we comparing glycerin to true Hyaluronic Acid? We exclusively buy Sodium hyaluronate. I know there's some kind of equilibrium in solution, just wondering  if companies are really buying as HA.

thanks

Perry

@EVchem - Of course, something must be strange going on here because I didn't think you could make more than a 2% solution of Hyaluronic Acid without it turning into a thick solid. 

MarkBroussard

@Perry:

Correct, something is not right with this study if they are claiming to have used 5% Hyaluronic Acid ... perhaps what they actually mean is 5% of a 1% Hyaluronic Acid solution.  

maria

Have you considered this study?

Please have a look at the "Fig. 4. Representation of the permeation and localization of various hyaluronic acid (HA) after fitting by their reference spectra and by comparison to the (a) positive (glycerin treated skin) and (b) negative (water treated skin) controls, (c) Cristalhyal (1000–1400 kDa HA), (d) Bashyal (100–300 kDa HA), and (e) Renovhyal (20–50 kDa HA)."

Seams like 1000–1400 kDa HA stays better at skin surface than glycerine and 20–50 kDa HA goes deeper, but thisis from my unprofessional point of view.

BTW my father had a Maserati and later on my mother had a Corolla, the only common thing was they were both gray.

Perry

@maria - Interesting. The study looks at the penetration ability of HA and shows that some versions penetrate deep in the stratum corneum. I don't agree that it shows that anything penetrates more deeply than glycerin though.

In reading the study, a few things occurred to me.

1.  The study just looked at the migration of HA through human skin samples. While it provides an interesting model, it says little about how the ingredient behaves on living skin. Things like moisture levels, NMF, blood circulation, etc may all have an impact on the migration of these materials.

2.  Glycerin goes everywhere any grade of HA goes. There is glycerin distributed throughout the skin both at the top and 100 micrometers down. In this way, Glycerin can be anywhere that any grade of HA can be.

3.  This study doesn't look at any end result of the treatment (e.g. moisturization). My initial contention that Glycerin works every bit as good as HA is gotten to by considering the end result of applying the two materials to the skin and taking measurements like skin moisturization, feel or any other property that a consumer would notice about their skin.

The only use study we have was the one posted above that showed glycerin outperformed HA.

Cst4Ms4Tmps4

After I spent so much money and effort trying Sodium Hyaluronate and Hyalyronic Acid due to my gullibility, I concluded that they are not as superior to anything. Really is a marketing thing.

Firstly, they boast God-given power to absorb water 500 to 1000 times their weight. Most thickeners and suspending agents can do it. Carbomer can do it and do it much better than HA/SH.

Secondly, it claims to 'hold' water due to the water-sucking power. Like Urea which everyone seems to say it is a humectant and very hygroscopic, I wet it and let it dry, it turns back to crystal/powder/solid.

Only after learning about a peculiar phenomenon called 'deep eutectic solvent' (credit goes to @Pharma ) did I see through the trick. I presume it is identical to layman's term "impurity". Only a little Citric Acid in Urea solution renders Urea liquid/syrup for ever. I thought it was low pH, so I tried with a little Propylene Glycol and a little other stuff, I obtained the exact same result--Urea just won't recrystallise. It was a WTF moment for me!

True enough, those so-called "tests" are a mixture of other things such as base cream as showed by @EVchem. The claim/marketing is a guaranteed failure if they tested it (any substance) as it is (single it out).
No different to Grapefruit Seed Extract as preservative-free natural-organic preservative, manufacturer never tells that it is laden with parabens, Benzethonium Chloride, Triclosan. 

I am not very sure about the "500 Dalton Rule".

Dr Catherine Pratt

very interesting perspective, how long have you been using cosmetics for? my husband was a brander with an advertising firm making TV commercials etc. The stuff that they come up with is really sad and a little short of total lies. The marketing department are good ones too. Allegedly in perfumery the perfumer will make a new perfume and when it gets to the marketing conference table, they are told to make it sweeter and that happens all the time.

Defeats the purpose hey!

I do have to say that parabens are not the bad guys they make out. In fact that is where the whole natural/organic thing really started and where I started to become specific. Everyone said it was just a phase but I took a gamble and yes the natural game is as strong as ever and the customers are as clueless as ever. Although I must say customers do want to read the label now and make their own choices. Is this good or bad???