Category: Ingredients

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Hyaluronic acid: the benefits in skincare.

Hyaluronic_Acid_formula

This post will make clarity on the benefits of hyaluronic acid for the skin and help you understand what kind you should be buying.

If you like to research ingredients and facts before making a purchase, you're probably facing an overwhelming number of information.

Do you know what I do when I feel overwhelmed? 

Absolutely nothing.

I don't take any action which can worse than making a temporary wrong decision.

THIS IS THE PROBLEM: too many options to choose from- a plethora of cosmetic ingredients.

Each one of them promises wonders.

How do you decide what to focus on?

There’s no univocal answer to this question, but I can share what I do as both cosmetic chemist and skincare junkie.

I focus on ingredients that 1) have scientific evidence supporting their action and 2) have a long history of usage with relatively no side effects.

This is why I ALWAYS include hyaluronic acid in my own formulations and in most of the formulations I develop for clients.

Hyaluronic acid is a staple ingredient in skincare. You can find it in serums, eye creams, lotions, and even rinse off products.

As a cosmetic chemist I know how some ingredients get the hype and then disappear after a few months.

But I'm also aware that there are ingredients that never lose their popularity.

Hyaluronic acid is one of these winners. 

Here's why.

It’s safe and effective. SAFE as it has a low irritation potential. EFFECTIVE as several scientific studies confirm its activity.

If you're interested in discovering the amazing properties and skincare benefits of hyaluronic acid, keep on reading.

What is Hyaluronic acid?

From a chemistry stand point, hyaluronic acid is a polymer. 

A polymer is a structure that consists in a large number of similar units bonded together.
In the case of hyaluronic acid the units are glucuronic acid linked to N-Acetyl- Glucosamine.

Hyaluronic acid is usually sold as sodium salt (sodium hyaluronate-powder), which releases hyaluronic acid in water.

The most important take home message is that Hyaluronic acid comes in different forms which have different molecular weights.
In fact, polymers have different weights, just like people. Molecular weight is determined by the number of units present in the polymer. The more, the heaviest.

  • High molecular weight HA ( 1.5 MDA). DA means Dalton which is a unit measure for weight. It's the equivalent to oz for very small weights such as molecules.
  • Low molecular weight HA (50kD).
  • Extra Low molecular weight HA.
  • Crosslinked HA (rare in skincare).

In the skincare industry, hyaluronic acid is considered a *humectant moisturizer.* It’s also useful for scars and wound healing.

When I write about Hyaluronic acid on Quora, people ask me all the time why I'm a strong proponent of high molecular weight and why I did not include medium or low molecular weight hyaluronic acid in the serum I developed.

Hyaluronic_acid_moisturizer

How does Hyaluronic acid work?

Hyaluronic acid is naturally present in the skin.
However, its content decreases with aging, and the most visible effects are *the loss of facial skin hydration, elasticity and volume, which are responsible for wrinkles.* This is how HA works as anti-age agent.

If you’ve been following my content, you should know that I’m always radically transparent; therefore, I must point out that *the anti-age activity has not been proven in clinical trials yet.


Over the last few years, HA has been widely used as a biomaterial to develop dermal fillers (DFs), which are medical devices that, injected into or under the skin, restore lost volumes and correct facial imperfections such as wrinkles or scars. This is the most effective way to take advantage of HA anti-aging properties.

Does this mean that skincare products based on HA are just a waste of money?

Actually, hyaluronic acid serums , when properly formulated, are among the simplest yet most effective products.

Here’s why.

HIGH MOLECULAR WEIGHT HA works as a *film-forming polymer:* it reduces water evaporation, with an occlusive-like action. Unlike other occlusive agents, though, it creates a cosmetically elegant film , rather than an oily thick and sticky barrier. The feel is light on the skin, the serum promptly absorbed so that you can apply a moisturizer right after it. 

 This is the main advantage of using it.

On the other hand,*MEDIUM and LOW MOLECULAR WEIGHT HA*mainly work by binding moisture from the environment meaning they act as humectants rather than moisturizers. In some cases, this capacity may reverse HA’s expected hydrating activity as at a high concentration, HA may even extract humidity from the skin, leaving it even more dry.

Furthermore, as this brilliant article explains in details, medium and low molecular weight HA are pro-inflammatory. These two forms of hyaluronic acid should be avoided especially when the skin barrier is already damaged and fragile.

The importance of the skin barrier.


Do you know what determines the overall appearance of the skin?

Water content.

"Barrier function,  skin elasticity, and resistance are all dependent on water content".

​

We all use moisturizers because we tend to have dry skin, right?

As we age, barrier function tends to become compromised. The worsening of the barrier function manifest itself with an increase in *TEWL* which stands for trans epidermal water loss. This basically means the skin loses more water than it is supposed to, thus becoming dry and dehydrated.

Hyaluronic acid is an humectant meaning it is able to draw water from the dermis (deep skin layer) to the epidermis (the portion of the skin that we can touch- the most external one).

This is why the immediate effect of using it a plumper and hydrated skin. 

Another approach to tackle dry skin is the use of creams that contain humectant ingredients; the most common humectants are glycerin, hyaluronic acid, sorbitol. urea, propylene/ butylene Glycol and its natural version propanediol.

 

However, when the skin barrier is damaged creams that only contain these ingredients not only can’t help, but they actually draw even more water from the skin, especially when used in very dry climates.



The best approach to tackle dry skin is the use of creams that contain *occlusive ingredients* (for example petrolatum a.k.a vaseline or lanolin). The problem is these creams are usually greasy, and therefore, not well tolerated, especially on the face. Furthermore, petrolatum and lanolin have raised health and environmental concerns.

The way these barrier creams work is by forming a hydrophobic (= water repellent) layer on the skin surface. This *mechanically* prevents water loss.

Instead of improving the situation, they actually make it worse.

Emollient ingredients help with dry skin, too, by improving softness, smoothness, and elasticity. Examples of emollients are fatty acids and alcohols or *vegetable oils.*

Extra dry skin benefits from the application of both , creams and oils.

Where does Hyaluronic acid stand?

As stated above, hyaluronic acid is an humectant moisturizer ingredient. But we have seen not all hyaluronic acids are equivalent.
High molecular weight HA is the only form that work as both, *humectant AND occlusive.*

This is a huge advantage.

Using a product with high molecular weight hyaluronic acid allows you to have the benefits of occlusive ingredients without their downsides (“heavy” formulations that are tacky and greasy) AND an dramatic increase in moisture due to its humectant properties.

Skincare products based on hyaluronic acid- The benefits. 

HA represents a moisturizing active ingredient widely used in cosmetic formulations (gels, emulsions or serums) to restore the physiological microenvironment typical (and the look, of course) of youthful skin.
HA’s hydrating effect largely depends on its molecular weight.

If you start including Hyaluronic acid in your skincare routine, you’ll notice a *plumper, softer and smoother skin*.

However, please remember that the skin is an organ and skincare products are no magic bullet, no matter how good they are. If you don’t sleep enough, your diet is off , and you rarely exercise, nothing will work.
Sadly you’ll end up switching from one product to another without any improvement.


This is why some people claim hyaluronic acid actually made their skin worse. 

Hyaluronic acid : skincare routine for dry skin.

dry skin
1

Avoid drying harsh cleansers. If it’s a face related issue, use micellar water or an oil based product rather than foaming cleansers. In particular, avoid all cleansers that contain sodium lauryl sulphate (SLS) and other anionic surfactants . These have an excellent cleaning and foaming power, yet tend to be aggressive. As a general rule, look at the foam. The more foam a product makes, the more aggressive it is.


Do not wash more than twice /day (face) and once / day body. If you don’t wear makeup, cleaning the face once /day is more than enough. If you feel you need to refresh it throughout the day, spray some water 

A great micellar water is the Bioderma Sensibio. 

2

In the morning , after you clean, apply a hyaluronic acid serum and layer it up with a moisturizer. The moisturizer should be very rich in ingredients such as Ceramides, urea, and cholesterol. An excellent moisturizer is the Clinique Dramatically Different lotion ($28 for 4.2 oz).

3

At night, before going to sleep apply a nightly moisturizer. The more occlusive, the better. So for instance even basic petrolatum will do. If you can’t tolerate Vaseline, these are 2 other options.

Remember that if you have dry skin you should limit alcohol intake and drink plenty of water.


By now you should feel quite enthusiastic about hyaluronic acid! 

​It should definitely belong to your skincare routine. 


​

Have questions? Leave them in the comments below.

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Coconut Oil as sunscreen: myth or reality?

coconut oil sunscreen

Coconut Oil as sunscreen: myth or reality?

As I was surfing the web, I found many blogs suggesting using pure and plain coconut oil as sunscreen.

I was very surprised; you see, I still remember my grandma applying oil to get more tanned, not the opposite. I also remember that once, after applying carrot seed oil,  she was exposed to the sun for too long and  that was a recipe for disaster.

Is it really possible to use coconut oil as sunscreen? How about other natural oils?

Even though coconut oil and other natural oils do a​bsorb UV rays at a certain ratio, their SPF is not enough to guarantee effective protection; however,  natural oils aren't useless when it comes to sun rays protection.

Keep reading to the end to discover how we can benefit from them.

Coconut oil SPF

Does plain coconut oil have a sufficient SPF value?

Why some people are turning to coconut oil as sunscreen?

We all know, to a certain degree, the benefits of the regular use of a sunscreen. It protects us from photo-aging and skin cancer. However, sunscreens have "side effects" and undesirable ingredients:

  • They can cause sensitivity. It can occur in the form of photoallergic reactions, including contact dermatitis. It's a very rare adverse effect, though.
  • Retinyl palmitate, an oil soluble form of vitamin A and  a widely used antioxidant in cosmetics and sunscreens is thought to increase the rate development of skin tumors. However, there is  a lack of evidence for this effect.
  • The presence of some ingredients suspected of being hormone disruptors, for example, oxybenzone.
  • The presence of ingredients known to cause reef bleaching (again, oxybenzone).

Is coconut oil really effective as sunscreen or it's just an hoax?

coconut oil sunscreen

Can we use coconut oil as sunscreen?

SPF (Sun protection factor) is defined as the UV energy required to produce a minimal erythemal dose (MED) in protected skin, divided by the UV energy required to produce an MED in unprotected skin.

What you need to know is that the higher the SPF, the more effective is the product in preventing sunburn. This means when a product with SPF 50 is applied, it will protect the skin until it is exposed to 50 times more UVB radiation than that is required to burn the unprotected skin.

Another way of saying it, is using percentages:, for example, SPF 15 filters out approximately 93% of all incoming UVB rays. SPF 30 keeps out 90% and SPF 50 keeps out 98%.

​​​​Here are the SPF values for some natural oils:

SPF values for some natural oils

SPF values for some natural oils

 These values have been taken from a study of the university institute of pharmacy, India.

According to this study, the natural oil with the highest SPF value is olive oil, followed by coconut oil. They both have a SPF around 7. According to the equation I showed you above, this means that the protection offered by both oils is only 7 times stronger compared to unprotected skin.

If a "traditional " SPF 15 product is able to filter out only 93%, with coconut oil, you basically can filter only 43%. Furthermore, other studies found coconut oil SPF values even lower.

I know for sure someone will read this article and say something like this:

"I have switched to coconut oil as sunscreen and it works wonders for me; I never get red".

Just because you don't see any redness, it doesn't mean your skin isn't screaming for help. UVA radiation penetrates deeper into skin and not only harms epidermal cells, it also damages collagen and elastin. Blood vessels can also be harmed. Photo aging doesn't show up with redness.


​Coconut oil in sunscreens


We can't use coconut oil as a solo sunscreen ingredient, but we can use it with other ingredients in lotions or sprays. Ingredients will act synergically to obtain a higher SPF protection.

​​​​If you want to explore natural sunscreen ingredients, consider  titanium and zinc oxide. These two are "physical sunscreens,": they deflect UV rays.

Formulating and selling sunscreen products: what you need to know.

selling sunscreen products

Sunscreen products in the US are regulated as both cosmetics and OTC drugs.

Formulating products with SPF can be challenging when you don't know what you're doing or you have no chemistry background.  Furthermore, the approval process takes longer and is more expensive. All this sounds discouraging for many brand owners.

Why formulating sunscreens is challenging?

There are additional factors to consider when evaluating a product's SPF. These include:

  • Other ingredients in the formulation such as solvents, film formers, emulsifiers and water resistant agents

  • Interactions between different ingredients

  • Ability of the formulation to be uniformly spread on the skin

  • The photosta­bility of the formulation

  • The manufacturing procedure which has to use adequate tools and machines for optimal dispersion.

To make things even more complicated, we need to consider that sunscreens are not tested in the same conditions when applying them on an everyday basis. The thickness of the film applied and the subject’s skin type play a role as well.

The fact that the effectiveness of a sunscreen depends on so many different factors explains why it's impossible to adequately calculate SPF from a combination of active sunscreen ingredients only.

What does this mean?

For formulators (including hobbyists), it means that we can't simply include 30% of titanium dioxide, and voila, obtain a 30 SPF. It's way more complicated than that, as we have seen.

We also cannot simply apply coconut oil on the skin and hope for the best, because of what we read on some "mommy blogs".

Sunscreens in the U.S

In the U.S, the Food and Drug Administration (FDA) classifies sunscreens products as both, cosmetics AND OTC, drugs. Being considered OTC drugs, they have stricter regulations compared to cosmetics only. The most important one is that their efficacy must be proven through in vivo tests on healthy volunteers (this is why the process is more expensive).

Furthermore, any product with sun protection claims must contain one or more active ingredients chosen from a list in the regulations. These ingredients include protective chemicals and ultraviolet (UV) filters, which must be listed on sunscreen labels.  

These are the active ingredients to choose from:

Aminobenzoic acid, Avobenzone, Cinoxate, Dioxybenzone, Homosalate, Menthyl anthranilate ,Octocrylene, Octyl methoxycinnamate, Octyl salicylate , Oxybenzone, Padimate O, Phenylbenzimidazole, Sulfonic acid, Sulisobenzone, Titanium dioxide, Trolamine salicylate, Zinc oxide.

This means that coconut oil won't be able to be approved as a sunscreen product because a) its efficacy cannot be substantiated and b) it's not on the FDA list above.

It's ironic that the EU, which is notoriously more cautious when it comes to cosmetic ingredients, has approved 27 molecules as sunscreen.

Conclusions

I hope I was able to show you why we can't use coconut oil as sunscreen...

Still coconut oil or other oils (for example raspberry or carrot oil) have a low SPF factor that can be useful when formulating sunscreen products. These natural oils can be used as "SPF boosters," so the formulation may call for a lesser amount of other active ingredients.

In the US sunscreens are regulated as both cosmetics and OTC drugs, making the approval process longer and more expensive.

This doesn't mean you shouldn't go for it.

It's more complicated, but it's what makes it even more important.

"Everyone wants to go to heaven, but nobody wants to die"

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If you want to start a successful cosmetic line, you need to be willing to do something that almost nobody wants to do. Take an extra step and add SPF to your facial lotions tested.

It's embarrassing how many lotions out there cost more than $50 and yet don't even have a SPF. It's okay if at the beginning you don't have the funds for these tests; BUT as soon as you reach a consistent level of sales, you should immediately improve your formulations by adding SPF active molecules.

You owe it to your customers.

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[List] Natural Preservatives for cosmetics

natural preservatives

Two days ago, I received an email from a potential client who wanted to hire me for an "intimate parts" product.

We scheduled a phone call to further discuss the project. During our phone conversation, I found out that this client wished to add probiotics to the product . 

My first comment was:

"There's no way probiotics can survive in presence of the preservative".

This is what that prospective client replied: "DON'T ADD THE PRESERVATIVE, THEN. "

There's a new horrible trend going on. It feeds itself on the (false ) belief that everything that is natural is good and vice versa. As a consequence, some brands started making and selling "preservative free cosmetics".

According to some people, preservatives are not necessary and can be even harmful. 

It's true that a high number of skin allergies and reactions are caused by preservatives and fragrances, but...this is not a valid reason to avoid using them.

What you can and should do is to inform yourself about the preservatives that are less likely to cause bad skin reactions. 

Want all natural products?

I get that.

But, even natural products should be safe and include a preservative! Just because you don't see any sign of spoilage, it doesn't mean it's not here. We know cosmetics don't have to be sterile. It would be quite ridiculous. At the same time, you don't want an excessive number of bacteria in them and no pathogen ones at all. Sure, not all bacteria, fungi, and mold are dangerous; however, even the innocuous ones could prevent the product from working the way it is supposed to.

As brand owner, you have the legal and moral responsibility of making sure the products you sell are safe. Period.

Myth #1: is glycerin a preservative?

Every now and then someone asks " is vegetable glycerin a preservative" ?

The question probably arises from the fact that products with a high concentration of glycerin usually don't require a preservative; BUT the glycerin has to be at least 50% which makes the products too sticky.

Furthermore, if you read some DIY blogs, you'll see that some other ingredients are labelled as preservative, yet they're not. To be precise, some might have antimicrobial properties , yet in most cases they're not enough to fully protect a water based product from spoilage. 

Let's see what these supposed "natural preservatives" are: 

  • Vitamin E is not a preservative. It's an antioxidant. 
  •  Essential oils are not ,generally speaking, enough to preserve a product from fungi, bacteria, and mold; however, it's absolutely true that essential oils have anti bacterial properties. The main issue with essential oils is that they tend to have a high affinity for the oil phase of an emulsion, thus limiting their accessibility to the water phase. Furthermore, they might be active against some bacteria , but totally ineffective against other strands. For example, it is well known that Tea Tree oil is not effective against Pseudomonas Aeruginosa. For this reason, if you do attempt to use them as preservative, make sure you use a blend or different oils rather than a single one.  Finally, other ingredients might interfere with their action; before you sell products with essential oils as preservative, make sure you perform the preservative challenge test. 
cosmetics_preservatives

"Omnia venenum sunt: nec sine veneno quicquam existit. Dosis sola facit, ut venenum non fit" (Paracelsus)

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As the wise Paracelsus figured out many years ago, the dose plays a crucial role as well; to exert their function as preservatives, essential oils should be present as combination and at high doses (sometimes more that 3%). These high doses are extremely irritant for the skin; this is why essential oils cannot be used as preservatives.

Are there cosmetics that don't require a preservative?

Yes!

Products with no water don't need a preservative; however, if you suppose they'll come in contact with water during use, then a preservative will still be necessary.

For examples, oils mixtures do not require a preservative as there's no chance bacteria are going to grow in them without water. From a stability point of view, though, oils still need something able to preserve their good qualities over time...they need an antioxidant.

Fats are well known to become rancid without a good antioxidant. 

Vitamin E is a popular and effective antioxidant. But let's talk about vitamin e as preservative...it doesn't work! 

To summarize, vitamin E does help to preserve a product, but from a physical stability point of view only. It is not able to kill or prevent bacteria growth.

Other products that don't require a preservative are those with pH values below 4 or above 8 and products with a high content of alcohol (perfumes), salt, or sugar.

Lotions always need a preservative system especially when the water phase is external.

Here's your ultimate list of natural preservatives for cosmetics 

cosmetics_preservatives

Bacteria, mold, and fungi can easily spread in a preservative free lotion.

As stated above, you should always add a preservative no matter if you want to keep your product 100% natural.

The good news is that there are many different all natural preservatives for cosmetics. Don't listen to whoever says natural preservatives don't work very well. I've formulated many lotions with all natural preservatives, and they all passed microbiological tests.

These preservatives can be used for skincare or haircare.

This list that also includes  organic & Ecocert approved preservatives. I keep the list updated with only products that I have personally tested and samples passed the challenge test.

Please feel free leave a comment with other natural preservatives options.

  • Benzyl Alcohol. Produced by plants, it has a pleasant odor and can be found in some essential oils ,too. It is considered a safe ingredient and helps dealing with Gram+ (Staphylococcus Aerus), Gram- (such as E.Coli, and Pseudomonas Aeruginosa), fungi, and yeast. Did I say pleasant odor? It looks like it is pleasant only for me as every time I ship a sample that contains it people claim they don't like the smell. Give it a try.
  • Dehydroacetic acid: a broad spectrum preservative suitable for Eco-label cosmetics. Can be used alone or in association with another preservative, for example Benzyl Alcohol. There are products that incorporate both Dehydroacetic acid and Benzyl Alcohol, for instance Geogard 221. Dehydroacetic acid has a pH dependent action; works best with pH below 6. It is also a very good anti-fungicide. Other acids effective as preservatives are sorbic and benzoic acid.
  • Glyceryl Caprilate with activity vs bacteria and yeast. It is Ecocert/Cosmos approved and works in a wide pH range (4 to 8).
  • Potassium sorbate is a natural preservative for cosmetics and food. It can be used in a wide variety of products including makeup, skin care products, hair care products, bath products, nail polish, fragrances, oral care products, spermicides, and insect repellants. It is highly soluble in cold water and works best at pH below 6.
  • Caprylhydroxamic Acid (and) Caprylyl Glycol (and) Glycerin (Spectrastat- Inolex). It's a  complete system for "preservative-free" claims cosmetics. It uses multifunctional agents that have excellent efficacy as biostatic and fungistatic agents.  It performs superbly at neutral pH and is compatible with most cosmetic ingredients. However, it can interact with residual iron found in some clay-type compounds (e.g., bentonite, silicates, etc). This interaction with iron may produce a very mild orange color or color.  It may be added to the water phase, at ambient or hot temperatures.  Lengthy exposure to elevated temperatures should be avoided. Typical use level is 0.7% w/w to 1.2% w/w.
  • Geogard ECT ( Benzyl Alcohol & Salicylic Acid & Glycerin & Sorbic Acid) is a natural broad spectrum Ecocert approved preservative. It's very common among natural products , especially in acid exfoliants due to the presence of salicylic acid which has a double effect (it acts as both exfoliating agent and preservative). The producer states Geogard ECT is water soluble, and it definitely is; however I've noticed solutions don't turn out completely clear. I recommend using it at 1%. Geogard preservative is active in a wide range oh pH (3 to 8). It is sometimes referred as Preservative Eco.
  • Sensicare M4200 or Geogard Ultra (Gluconolactone & Sodium Benzoate) is a water soluble broad spectrum preservative that also improves the moisture content. It is widely used in makeup , especially pressed powders. It is compatible with the most common ingredients including cationic, anionic and non-ionic surfactants. It's stable over a wide pH range from 3 to 7 and at high temperatures. It can be added to the water phase at room temperature as well as at higher temperatures. Use it at a % between 1 and 2 in both leave on and rise off products. It complies with  Ecocert/COSMOS standards for preservatives.
  • Anisic acid is a compound with anti-fungal activity only; therefore, it needs to be associated with other preservatives that have anti bacterial activity. Trade name for this molecule is Dermosoft 688 by Evonik Dr. Straetmans GmbH. Smaller amounts for can be purchased from Essential Wholesale Website. The acid form is a bit tricky to dissolve in water...to increase water solubility, you can use the sodium salt instead.
  • Glyceryl Caprylate (and) Glyceryl Undecylenate: this is a recent preservative system that is quickly gaining popularity. It's present in a large number of natural products probably because it's versatile and effective. The composition has also emollient, co-emulsifier, and skin re-fatting properties. It may be incorporated in the oil or water phase at any point during the emulsification process. For optimal results make sure the final formulation has a pH of  5.5 or lower. Trade name is Lexgard Natural by Inolex. Small amounts can be purchased here.
  • Naticide: with an appealing INCI name of "parfum" this preservative is perfect for whoever doesn't want to list a preservative in the actual ingredients list, supporting the "preservative-free claim".  Naticide has wide spectrum of activity, being effective against Gram+, Gram-, yeasts and moulds in a pH range between 4 - 9.  Naticide has also the COSMOS certification.  Buy it from Amazon.  According to Sinerga , the Italian company that makes Naticide, it should be used at 1% . Furthermore, it should be equally divided in the 2 phases (0.5% in the oil phase and 0.5% in the water phase). If using this Ecocert approved natural preservative, you'll have to list it as fragrance in the ingredients list.
  • Ethyl Lauroyl Arginate: this is a food grade surfactant that also has antimicrobial properties. It can be the perfect natural preservative for hair products as it  exhibits good activity against Malassezia Furfur which is responsible for dandruff. Furthermore, it shows good activity against Propioninbacterium Acnes which, as you can guess, is responsible for acne. This preservative is not skin sensitizing or irritating. ELA shows activity between pH 3 and 7 against bacteria, mold, and fungi.
  • Biosecur is a 100% natural preservative made from citrus extract.It's Ecocert certified and USDA organic. Therefore, it's a great option for organic lotions. It's distributed by Sharon worldwide. More information available here.

This is my favorite natural preservative (if something like favorite preservative exists ?).

MINASOLVE GREEN B (more info here). Ecocert/Cosmos Approved. INCI: Pentylene glycol (and) Water (and) Sodium benzoate (and) Benzoic acid. Recommended use level : from 1% to 3%. Works best at pH below 6. 

Don't get me wrong, though. There's no such thing as a "best natural preservative". You need to base your choice on the overall formulation, cost, and availability.

Would you like to receive the first chapter of my latest ebook? Just write your name and email below!

Formulating with natural preservatives like a pro: guidelines and tips.

I don't know how familiar you are with preservatives, but I am pretty sure you know that there's tons of them out there. 

How to choose the right one (or the right combination)? 

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    Rule #1: pick a preservative among those in the Annex V of the EU cosmetic legislation (regularly updated). Remember, when it comes to cosmetic regulations always take Europe as a reference. The cosmetic industry is highly regulated over there and ingredients are "approved" based on their safety profile. Maximum allowable amounts for a single preservative are also listed. You can find the Annex with the list here. For example , the above mentioned Benzyl Alcohol is allowed at 1% maximum. 

When it comes to cosmetic regulations, always take EU as a reference.

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    Rule #2: Always include a preservative booster. These ingredients help the preservative to penetrate the microbes cell walls. Some of the most common preservative boosters are: glycerin, ethylhexylglycerin, butylene glycol, and pentylene glycol. If you're looking for a natural booster, I suggest Propanediol (trade name Zemea).
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    Rule #3: don't forget to add a chelator to the formula. Chelator agents such as EDTA are usually added at 0.05%. Nevertheless, they play an important role in the formulation. An amazing natural alternative is Sodium Phytate (highly water soluble as EDTA).
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    Rule #4: check your pH. Some preservatives only work within a specific pH range, so you want to make sure your product's pH falls inside the range. This information should be provided when you purchase the preservative. Remember to ask if it doesn't happen. When you have to calculate small pH intervals, strips are not the best choice. Invest some money into a pH meter. Usually if they're cheap, they're not very accurate...If you don't know what to buy, below you can see two valid options (the second one is perfect for semi-solids such as creams). Remember to calibrate the instrument before each  use, or the measure won't be accurate. For other tools to build your cosmetics lab, check this post
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    Rule #5: work following the GMPs (Good Manufacturing Practices). In the pharmaceutical world, it's common to say that "the quality of a product doesn't need to be checked, it needs to be built". Don't waste time by creating a product and checking if it's good enough afterwords (=passes stability tests). Instead, use a set of fixed principles that allow you to create a product you already know will pass stability tests. In the specific case of preservatives, do not add a lot of them to compensate for a poor lab manufacturing hygiene. Make sure you follow the GMPs and periodically check and sanitize working areas and instruments. To sanitize use alcohol or bleach. Avoid tap water and make sure your raw materials are not contaminated/expired.
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    Rule #6: always combine two or more preservatives, a.k.a use a "preservative system" to obtain a broad-spectrum protection. Remember to add an anti-fungal compound as well (for example, sorbic acid).
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    Rule #7: Perform microbiological tests! Send 2 oz of the product to a qualified lab for PET test ( Preservative Efficacy Test). During PET test the product is intentionally inoculated with bacteria to see if the preservative can withstand them.  Lastly, perform one test to make sure your product contain a limited number of bacteria AND NO pathogens (not all bacteria are pathogen). Positivity if the PET test means you need to change the preservative system. Positivity in the 2nd test means the product was already contaminated so make sure you review the production procedure and follow the GMPs. Want to perform a quick, inexpensive, DIY test? Then you might want to check this link out.
  • check
    Rule #8 (lotions only). Add a preservative in the water phase and the other one once the emulsion has been formed (cooling down phase). Do not add the preservative when the lotion is still hot. As said before, make sure the pH of the water phase is acid (you can use citric acid to lower the pH ).

Natural preservatives for cosmetics: conclusions.

In this post we have learned that water based cosmetics (for example hair products, face masks, lotions, makeup etc) do need a preservative to perform the way they're supposed to and to be safe.

We have also learned what are the most popular natural preservatives for cosmetics and how to formulate using them; my final recommendation is to try those that are aligned with your or brand's values and see which one gives you the longest shelf-life. 

Finally, to test shelf life and efficacy, you'll need to perform PET test (Preservative Efficacy Test). Since this kind of test can be quite expensive, I would recommend to try using a microbial Test kit before. It consists of a plastic slide coated on one side with terrain for bacterial growth and on the other side with Agar for yeast and mold growth.  

Now I want to hear from you! What is your  natural preservative of choice when making skincare? 

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[Cosmetic Ingredients] What is dimethicone?

Dimethicone in liquid lipstick
[content_container max_width=’700′ align=’left’]In this post, I’ll answer to

“what is dimethicone” and

“what is dimethicone used for?”

I’ll also cover some possible alternatives if you don’t want to use silicone in your products.

Let’s start!

Recently, I’ve been discussing a face serum formulation with one of my clients. He is the co-founder of a natural skin care company in NYC.

He was facing a dilemma.

Simply put, he didn’t know whether or not adding dimethicone to the formula.

One one side, he didn’t want to “betray” his customers. Indeed, one of the reasons for their loyalty was the fact he was using only natural ingredients. On the other side, he was aware of how dimethicone can positively affect the sensory performance of skin care products.

He asked for my advice. Do you want to know what I recommended? Then keep reading.

Let’s start from the beginning.

What is Dimethicone?

Dimethicone is a cosmetic sensory enhancement ingredient that belongs to the silicones category.

Silicones are a highly controversial class of ingredients. Chemists usually love them because of the sensory aspect (especially in skincare and haircare). Consumers are sometimes worried when reading dimethicone on the product label. In fact, silicones have a bad reputation, being accused of:

  • Comedogenicity ( the process of exacerbating acne ).
  • Occluding the skin without letting it “breathe”, sweat etc.
  • Provoking skin irritations.
  • Having a negative environmental impact.

Let me tell you something.

I don’t like to formulate with silicones or using hair care products that contain them.

Yet, I can guarantee they are safe, non-comedogenic, and have no negative impact on the environment (silicones are pretty stable and inert polymers but, being hydrophobic, don’t accumulate in the soil).

[thrive_highlight highlight=’#87e033′ text=’light’]NOTE: if you’re pregnant, contact your doctor to make sure it’s okay to use dimethicone-based cosmetics.[/thrive_highlight]

 

The majority of silicones are water vapor permeable and this makes them non-occlusive at all. Silicones with occlusive power are, for example, cetyl dimethicone (semi-permeable) and C30-45 alkyl methicone which is as occlusive as petrolatum.

Polymeric films formed by some silicones are able to resist wash-off; it might not a bad thing like some blogs claim.

Actually, it’s a good thing. Not only it prevents water loss from the skin, but it also favors the penetration of active ingredients contained in botanical extracts or oils. Also, it becomes extremely useful with sunscreens that have to be waterproof, for instance.

For sunscreens, resisting wash off becomes crucial (waterproof claims).

I bet you are also familiar with some particular skin conditions that need to be treated with topical medications. These creams are always highly occlusive. By preventing easy wash-off,the active ingredients stay in contact with the skin for a longer period of time and this favors their penetration rate and extent.

The downside is that these creams are difficult to spread, thus limiting patients’ compliance.

Silicones are not comedogenic either and are perfectly fine for the skin.

Trust me.

“So, why don’t you like formulating with them?”

I am going to explain this using a metaphor.

I feel it’s like cooking using too much grease. Yes, the food tastes awesome, but it’s only because the cream (or butter or whatever) is covering all other flavors. I mean, the challenge is supposed to be cooking tasty dishes using only a limited amount of fat because everyone is able to do the opposite!

The same concept applies to the use of silicones in cosmetics. The real challenge for a cosmetic chemist is being able to formulate a product with a satisfactory sensory feeling and without dimethicone. Furthermore, based on my personal experience as cosmetics user, the beneficial effect that silicones impart to my skin or hair is only temporary while other emollients can provide a longer effect. Finally, silicones are usually cheap, and I don’t see why I should pay $40 or more for a cream that lists dimethicone as the second ingredient after water.

Don’t believe whoever tells you it’s impossible to formulate without dimethicone!

Today, up to 40% of all new products introduced in the U.S cosmetic market contain silicones. Silicones arrived in the cosmetics and toiletries industry in the 1950s, when low levels of medium-viscosity dimethicone were used to prevent the whitening effect of soap-based skin lotions. Nowadays, they are ubiquitous.

 

Why are silicones so popular?

The main reason why silicones are used in almost all kinds of skin and hair care products is their sensory properties. They deliver greater emollience values than many commonly used cosmetic ingredients both during and after application. Silicones are able to provide a smooth, velvety, and nongreasy nor oily feel.

Volatile silicones provide slight lubricity, a light texture, fast spreading, and good distribution of the product during application. The word volatile means that the evaporation requires less energy compared to water. This particular kind of silicones is the basis for long-lasting/nontransfer decorative products, especially lipsticks. Their aim is to disperse pigments, improve the application, and impart a pleasant skin feel. In modern liquid lipsticks, silicones allow obtaining a complete smudge and water proof performance.

Hydrocarbon-based emollients (for example, mineral oil) do have a greasy or oily feel and silicones are often used to mask it. Silicone elastomers (for example dimethicone cross polymer) confer a dry, powdery feel to skin care formulations.Dimethicone is able to give a more lubricious, longer-lasting effect in richer, more nourishing skin treatment products such as night creams or after-sun products.

Finally, silicone acrylate copolymers have the ability to form non-occlusive films that resist wash off. This film-forming property is useful in sunscreens.

How to recognize silicones in the ingredients list

If you’re like me, you want to be able to make your own independent choices when it comes to purchases. As carefully reading the labels is pivotal when it comes to food decisions, the same applies to beauty products.

To recognize silicones, look for everything that ends or contain  “cone”, “siloxane” or “silicate”. If unsure, post the name of the ingredient in the comment section.

 Silicones in hair products

Silicones are so popular in hair products because they’re able to:

  •  Conditioner the hair and make the combing process easier.
  • Provide a sensory enhancement ( soft and smooth feel).
  • Reduce the drying time and therefore limit the damages caused by high temperatures shock (blow drying).
  • Boost the formation of foam.
  • Improve the shine, confer and fix a “natural look”.
  • Work as color retention aids.
  • Strength and protect the hair ( the film may protect the hair cuticle during elongation, and assists in sealing the hair cuticle, helping to maintain an optimal moisture level for hair strength).

Are they 100% necessary?

No, they’re not (personal opinion).

Mineral and vegetable oils can be as good.

Coconut oil, because of its low molecular weight and straight linear chain, penetrates the hair and reduces the amount of water absorbed, leading to a lowering of swelling. Applying oil on a regular basis can enhance lubrication of the shaft and help prevent hair breakage. Coconut oil, being a triglyceride of lauric acid (principal fatty acid), has a high affinity for hair proteins. Mineral oil does not penetrate while sunflower oil only partially not reaching the cortex.

coconut oil

[thrive_highlight highlight=’#87e033′ text=’light’]PRO TIP 1: no matter how good an il is for your hair. When formulating shampoos, remember that the amount of oil should be limited as nobody likes the greasy feel.[/thrive_highlight]

Other common conditioning agents for hair are the quaternary ammonium compounds (the “Quaternium” family). They are very effective to make the hair feel soft, smooth and easy to comb. Quaternium compounds have a positive charge located on the N atom and, therefore, are noncompatible with anionic surfactants which carry a negative one.

[thrive_highlight highlight=’#87e033′ text=’light’]PRO-TIP 2: lowering the shampoo pH to 5 can help decreasing the hair frizziness by generating less negative static electricity on the hair fiber surface.[/thrive_highlight]

Alternatives to silicones

Are there ingredients that perform as well as silicones?

Of course. Many, actually.

Here are some examples.

  • Polydecene and polybutene. These are hydrocarbons and can replace dimethicone or Cyclopentasiloxane without modifying the overall formula or performance due to their silicone-alike texture and volatility.
  • PPG-3 Caprylyl Ether. This is a plant-derived conditioner ingredient.It’s a low viscosity colorless liquid that imparts shine and doesn’t reduce the volume. It also provides a silicone-like texture. Can be used in both shampoos and conditioner, alone or in association with silicones (reduce their amount by 25%).
  • Diheptyl Succinate (and) Capryloyl Glycerin/Sebacic Acid Copolymer. My favorite Cyclomethicone replacement. It is completely biodegradable and Ecocertified. Feel free to use it in both skin care products and shampoos/conditioners.
  • Isohexadecane with excellent spreading and emollient properties. Odorless, it has an extremely light feeling.
  • PEG-4 distearyl ether (and) sodium Laureth sulfate (and) distearyl ether (and) dicaprylyl ether (Lamesoft Care_BASF). This composition is well suited for surfactants based systems which means body washes and shampoos. It offers conditioning and anti-hair breakage and consists of waxes, emollients and micronized lipids. It imparts a typical marble white appearance in the final product.
  • Dicaprylyl ether (and) decyl glucoside (and) glyceryl oleate – Plantasil by BASF. This composition is suitable for clear shampoos, body/face washes. It is able to dramatically improve the conditioning performance and it is completely naturally sourced.

NOTE: as stated above in this post, silicones form a thin hydrophobic film that protects the hair (by sealing the cuticle). It is always better to act from within using ingredients that are able to penetrate the hair. One of these ingredients is low molecular weight Hydrolyzed Wheat Proteins. These protein repair damaged hair.

On the scalp, panthenol (pro vitamin B5) is converted into pantothenic acid which is physiological in the hair. It is able to penetrate into the cortex where it helps repairing damages caused by perming and coloring.

Glycerin is able to penetrate the hair, too! Once inside, it restores moisture to damaged hair.

When using ingredients that need to penetrate the hair in order to exert their beneficial effects, remember to allow enough time for the penetration (at least 10 minutes) or opt for leave-on conditioners.

Formulas: shampoo and lotion

General Rule: when in doubt whether using silicones or not, always try the same formula with and without and evaluate the differences (if any).

Regardless of many different claimed benefits, the main goal of all shampoos is to remove dirt from the hair. Therefore, surfactants will be necessarily in the formula along with water and a preservative system. I also suggest glycerin and panthenol for the reasons stated above.

Here’s a basic shampoo formula for you to play with.

Some ideas to customize this formulation:

  • Replace part of the water with aloe juice, or other water (I love orange or cucumber water).
  • Add some extracts in the water phase. Rosemary and sage extracts add sheen to brunette hair, while chamomile gives natural highlights and softness to blond hair.
  • Vary the surfactants. Surfactants like Sodium Laureth sulfate are the cheapest, indeed. Yet, they’re very aggressive on the skin.

Lotions don’t need silicones, too!

I put together a natural lotion formula so you can familiarize with skincare making. It is possible to add Cyclopentasiloxane in phase C, but it is absolutely not necessary. If you need to shop for equipment, check this post

Access the formula from HERE

Conclusions

Even though dimethicone and its derivates are present in many different cosmetics products, their use is questionable and controversial.

Silicones are safe and non-toxic, yet it doesn’t mean they’re beneficial for everyone.

As a consumer, I only use silicone-free shampoos and conditioners, while I don’t have any problem in using lotions that contain silicones as long as they are in a very limited amount.  I am not implying silicones are bad for hair in general; they just don’t work for me, but they might be perfect for you.

This is my favorite silicone free shampoo.

This is my godsend leave-on protein cream. I use it as hair conditioner. It really leaves my hair silky-smooth. Try it and let me know if you like it.

As a formulator, I consider silicones pivotal in some products. These are sunscreens, some makeup products (for example liquid lipsticks and foundations) and serums.

In the end, my client decided to go without dimethicone. In his case, this was the right decision as his brand has always proudly used only natural ingredients.

A blog is no fun without any interaction between readers…leave a comment below and get the discussion started!

What’s your opinion on silicone?

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