I challenged Marta Ferreira, from the Blog The skin I live, writing with me articles on the Hair Schedule and the Curly Girl Method analyzed in the eyes of science, in a series of 4 publications.

The first article in this series can find here, the second here, the third here it’s the room here.

Contenido del post

Can hair finishing be done with conditioner or just finishing creams?

Both of these products have the function of facilitating the act of combing the hair, through the lubrication of its shaft and can leave some residue on the hair when used.

In terms of composition, these products are apparently similar.

However, caution is needed when using the conditioner to finish the hair due to the possibility of having preservative ingredients in certain quantities that are not allowed by the EU in non-rinse products (such as methylchloroisothiazolinone and methylisothiazolinone) as they may contain a greater concentration of these ingredients and may lead to contact allergy. In the case of styling creams that are not rinsed, the concentration of ingredients that may leave residue on the hair will be slightly reduced and will be able to be left on the hair as they are formulated for this purpose. (1)

What ingredients protect hair from UV rays?

For the summer, at a time of greater sun exposure, using a product with UV protection should be useful to prevent hair from being damaged by the sun’s rays – the sun increases the porosity of the hair and can even modify the natural color.

The most common ingredients in hair care products are: Octylmethoxycinnamate (ethylhexyl methoxycinnamate or octinoxate), Cinnamidopropyltrimonium chloride, Benzophenone-3, Benzophone-4 and Quaternium-95.

However, it will be difficult to determine in these products leave in what is the concentration of these ingredients, if they effectively protect the hair completely from UV rays and if they will be evenly spread over the hair depending on the amount applied, since the concept of sun protection factor does not apply to hair. It is necessary to bear in mind that although the cream protects from sunlight, it does not mean that the hair does not look dry due to heat dehydration.

A good way to protect your hair from lightning is to wear a hat with a denser fabric that can cover much of the sunlight.

Humectants / Anti-Humectants in hair on damp days – Glycerin and other humectants in finishing creams on rainy and humid days cause more frizz?

Antes de mais, é importante esclarecer que o conceito “anti-humectante” não existe. Este termo é por vezes usado para se referir a ingredientes emolientes e oclusivos, visto que estes limitam a permeabilidade do cabelo à água, mas estes ingredientes não só não impedem a humectação, como melhoram também a sua durabilidade. Humectante significa que atrai água, no entanto, esta categoria pode envolver imensas categorias de ingredientes, incluindo sais, glicerina, extratos de plantas, ácido hialurónico, proteínas hidrolisadas, sodium PCA, ácido láctico, ureia, e outros ingredientes, mas nem todos são iguais, e podem comportar-se de forma diferente no cabelo. (2)

On the other hand, and since humectants are very soluble in water, it is not clear that these ingredients try to be highly effective in rinsed products, since a large part can be eliminated during rinsing.

Regarding creams leave in, it is impossible to draw this kind of generalist conclusion: nobody knows what percentage there is in a product, even by reading the list of ingredients.

Why is a hairdressing product more expensive than a supermarket product?

congratulationsIn terms of ingredients, the price should not be much different, since the suppliers of raw materials are the same for all companies. And although there may be slightly lower prices for those who buy in large quantities, but there can be no better glycerin than the other, for example. Glycerin is exactly the same molecule regardless of origin, and the purity is similar at all suppliers.

Just like white and commercial brand drugs – Benuron’s Paracetamol must be the same as any other that contains Paracetamol.

As marcas pagam também pelo extra da formulação: a embalagem, o rótulo, o marketing, o nível da prateleira de supermercado, onde vendem e se apenas querem ser vendidos nos cabeleireiros e farmácias, etc. Isto aumenta logicamente o preço do produto. Por outro lado, algumas marcas mais caras podem ter patentes exclusivas que encarecem os produtos. Contudo, o facto de existir uma patente não significa que o produto que a contenha seja necessariamente melhor. Só significa que existe inovação.

In terms of safety, any formulated product must comply with legislated safety rules. Just think that many of the supermarket brands belong to the same pharmacy or hairdressing companies, that is, we can see that whoever formulates, produces and controls these products has a very solid and reliable structure.

For example, L’Oreal owns brands like Kérastase, Lancôme, Redken, Garnier, etc. Does this mean that all formulas of these products are similar to each other? Not necessarily, but some will be almost the same! A good way to understand this is to read the label to get more knowledge of the product they are about to buy.

Is it possible to know whether one anionic surfactant is stronger or not than another? Which anionic ingredients are the most and least aggressive for the scalp?

Shampoo with SulfatesYes, there are more detergent anionic surfactants than others.

However, as mentioned in previous publications, it is not possible to determine whether a shampoo is more detergent or not just by the surfactants it contains. Shampoos are essentially a combination of surfactants that serve to dissolve oils as well as grab dirt particles.

Therefore, choosing or refusing products simply because they contain “Sodium Laureth Suphate” does not make sense, and we may be paying more for an “Sulfate Free” product unnecessarily.

What ingredients are heat protectors in the hair?

aloe vera capillary timelineDamage to the hair fiber begins (denaturation of the hair protein) after 100ºC. High temperatures can cause 3 types of hair damage: decomposition of the hair pigment that leads to a change in its color, damage to the surface of the hair fiber that causes the hair to become rough and without natural shine and weakening of the proteins inside the hair wire, leading to breakage.

There are 3 theories to explain how these products work:

– uniform heat distribution – products that leave a layer in order to prevent direct contact between the hair and the utensil. This protective layer helps to minimize the effects of excessive heat.

– reduced heat conduction – any product that makes the hair more malleable can say that it protects from heat, because if the straightening irons slide more easily and quickly through the hair, there is less chance of damage – this effect can reduce the high temperature momentarily and decrease the damage.

– oxidation prevention – at least one study suggests that thermal decomposition of capillary protein is caused by a reduced oxidation action. (3)

There are hundreds of products that claim to protect hair from thermal actions, of those studied, the literature talks about PVP / DMAPA acrylates copolymer, Hydrolyzed Wheat Protein and Quaternium 70 that had good results in hair in creams leave in and when listed at the top of the list of ingredients. (4)

However, it is necessary to realize that a product is formed by a set of ingredients in a formula and not by just one, being that it will be very unlikely in the same way to predict the quantity of these ingredients in the products and their effectiveness, since there is no legislation for this type of products.

Is it possible to have “excess protein” in hair derived from hair products / masks and lead to breakage?

Hydrolyzed proteins that have a weight of 1000 Daltons or less are those that bind best to hair. Smaller than 500 Daltons can penetrate the hair. (5)

Despite this, hair keratin is irreparable when it comes to its shape and hair protection properties, and the use of amino acids in hair products does not replace or restore any damaged molecular structure. Especially because the damage does not consist only of the loss of molecules, but of entire scales of the hair cuticle.

The bottom proteins are conditioning ingredients that help reduce friction and frizz and can help improve the overall look of the hair.

Larger proteins function more as ingredients that will deposit in the hair, than in the more porous hair it will fill in the gaps and improve its surface. This type of protein will help to attract hydration to the hair and this helps it not to break down so easily.

On the internet there is a reference that you should not use products with protein very often because they may lead to breakage of it.

It is believed that this myth emerged from the African American community, which, when relaxing, obtained a more porous hair and when using these products with a large amount of emollients it made the hair “stiff” and brittle. That is why specific products for people started to be formulated after certain chemical procedures on the hair. (6)

Hydrolyzed protein can have several functions, such as forming a film around the hair and even reducing the loss of hydration in the hair. (7)

For this reason, there is no basis that justifies hair breakage due to excess protein.

There are products that are “heavier” in terms of consistency than others, can we see that by looking at the composition before buying it?

Silicones in HairPoderá ser benéfico reparar se a lista de ingredientes tem grande ou pouca quantidade dos ingredientes que podem causar acumulação no cabelo: silicones, óleos minerais e vegetais, manteigas, ceras e tensioativos catiónicos. Normalmente os ingredientes estão por ordem de quantidade (maior para menor quantidade) e isto poderá dar uma indicação de quanto resíduo o produto pode deixar sobre o cabelo, mas tal como vimos não pode ser encarado de forma alguma como garantia, já que o acabamento do produto depende da interação entre todos estes ingredientes com a restante formulação, e não da sua presença.

Thus, it will be more interesting which type of hair the product is intended for, which its texture (creams tend to be heavier than sprays, for example) and which finish the brand proposes (wet, light, texturizing effect) , etc.).

Can I do Co Wash exclusively?

O Co Wash pode ser interessante para quem lava o cabelo diariamente por exemplo, mas deverá alternar-se com um champô com uma ação mais detergente para limpar o cabelo a fundo da possível acumulação de resíduos. A maioria dos champôs são aniónicos enquanto que os condicionadores são altamente catiónicos e vão por isso ser atraídos para as partes mais estragadas do cabelo (que têm carga mais negativa por perderem ligações dissulfeto). Por isso mesmo, os condicionadores não são bons a agarrar sujidade, células mortas e oleosidade no couro cabeludo e cabelo. O condicionador foi formulado para deixar resíduo no cabelo, mesmo que seja feita uma boa massagem no couro cabeludo: deixa sempre algum resíduo.

If used every day, the day may come when it will start to accumulate too much residue on the scalp, on the hair and become “heavy”, without natural curls. It may also attract more dirt from the air. Frequent washing with conditioner can lead to dandruff and other types of inflammation on the scalp.

In this sense, exclusive washing with Co Wash is not recommended for those who have normal or oily scalp, wash their hair infrequently, or use finishing products without rinsing after washing.

Does overuse of sulfates really do harm?

hair heat damageThere are some studies that mention that shampoos with a very detergent action are often used in a routine that can lead to hair becoming drier and with irritation on the scalp. (8)

If a shampoo contains sulfates, but if they are present in a reduced concentration or if the product also contains several oils, non-ionic surfactants or even some silicones; this product is likely to have a mild washing action. And in fact, we will only know this by experimenting, and checking how the hair looks after washing, or by the amount of foam it can make (which can, however, also be a misleading experience, since there are ingredients that increase the formation foam without giving more divergence to the product). (9)

Do No Poo / Low Poo – Should I use a sulphate shampoo?

final washO facto de o champô conter sulfatos ou não pouco diz acerca da sua ação lavante ou se é muito agressivo ou não para o cabelo. Neste sentido, a procura de tensioativos SULFATE fornece apenas uma indicação, e nem sempre nos permite verificar se esse produto é adequando. É assim mais pertinente ler o rótulo do produto, por forma a perceber a que tipo de couro cabeludo esse champô traz mais benefícios.

Esta opção também difere da rotina da pessoa em questão: se tem tendência a fazer lavagens capilares diariamente, então o melhor para a saúde da haste capilar será usar um champô de baixa ação detergente, sendo indicado para couro cabeludo seco (os denominados low poo) ou então experimentar o no poo/co wash. Caso o couro cabeludo seja oleoso, o uso de champô tradicional ou low poo terá mesmo que ser frequente. Se a rotina deste tipo de cabelo passar por ficar muito tempo sem ser lavado, o melhor será usar-se sempre low poo entre as lavagens e usar-se sulfatos esporadicamente, para remover toda a possível acumulação de produto que poderá surgir com o uso de cremes finalizadores.

At the end of the day, the decision will always be up to the person and what they think is pertinent to add to their hair routine, but no, sulfates are not the enemy if used well!

Explains the difference between soluble and non-soluble silicones and whether soluble should be compatible in the method.

In the world of curly hair, the difference between soluble and non-soluble silicones is mostly mentioned.

Fluid (insoluble) silicones can leave residue on the hair, and the amount of residue deposited will depend not only on the type of silicone, but also on the concentration it is in and the rest of the formulation.

Water-soluble silicones (such as silicones containing the prefixes peg, pg- and ppg and waxes such as emulsifying wax, emulsifying wax nf, peg 8 beeswax, peg-75 lanolin and peg-8 beeswax), do not mean that they come out with water, but rather that they dissolve in it and can also leave hair with some residue, since that is its function. Quaternary ammonium compounds (polyquaternium-X, bentrimonium chloride for example), are water-soluble but being able to make connections with the hair cuticle will not be rinsed (and thankfully!).

Some silicones that evaporate are for example Cyclomethicone, Cyclomethiconal, Cyclopentasiloxane and Hexamethyldisiloxane.

Once again, these ingredients are present in the products to facilitate styling, reduce frizz or make hair smoother; so the product that contains them should be chosen according to the condition of the hair shaft, adapting the amount of product applied and the products used in washing to the condition of the hair.

Can soluble silicones accumulate in hair?

It depends – but it is necessary to keep in mind that silicones are not alone in a formulation – they are accompanied by other ingredients in hair products and these ingredients may even accumulate more than the silicones themselves – the problem of the formula accumulating in the hair may not be due to fault of silicones, but of all the ingredients of that formula.

Silicones are more complex than they appear. There are for example some silicones that after rinsing the hair leave no residue, such as volatiles, and then there are other silicones that are heavier in weight and leave residue on the hair, such as dimethicone. These will lubricate the hair and help with frizz.

In the Curly Girl Method, any product with a certain ingredient is avoided, but a product with silicones at the beginning of the list of ingredients and another at the end, can it be said to have the same effect?

They may or may not have the same effect depending on the set of ingredients in the formulation. Comparing two products in which silicone is at the beginning of the list and another at the end, it indicates that the first product has more silicones than the last in theory, but, however, it is impossible to know the true concentrations of each ingredient in the formula. The first product may have silicone in first in the list and accumulate less residue in the hair than the second, for example, it will all depend on the set of the formula in question.

There are those who say that silicones never come out of the hair, being necessary to have a capillary transition, right?

The word silicones designates a class of molecules very diverse, and for that reason it does not allow us to make generalizations. Some silicones do not have the chemical capacity to permanently bond to hair, but others are modified specifically for this purpose, such as Amodimethicone. Some will have to leave with a shampoo, others will not, and others may be eliminated over several washes.

Will a more vigorous massage with conditioner (Co Wash) clean it in such a way that it is not necessary to use shampoo?

oily hairO Co Wash/No Poo não consegue substituir o champô porque não possuí micelas suficientes para fazer espuma e retirar a sujidade do cabelo. A maioria dos praticantes desta técnica sente necessidade de alternar com um champô com tensioativos aniónicos (que faça espuma) para remover o excesso de resíduos e sujidade. A massagem pode ajudar a retirar resíduo do cabelo, e é muito importante para que o Co Wash tenha alguma eficácia, bem como para evitar que se acumulem resíduos do próprio produto. No entanto, esta massagem por si só não substituí tensioativos que limpam o couro cabeludo com mais eficácia.

Is this distinction on the part of people of products by their ingredients correct?

Será que se fosse fácil saber exatamente qual a performance de um produto através da análise da lista de ingredientes haveria tantos métodos para um mesmo propósito? De que forma é que um leigo pode compreender uma formulação de um produto cosmético, tendo em conta que o glossário de ingredientes da Comissão Europeia contém 26491 entradas? De que forma podemos fazer este tipo de previsão sem conhecer o modo de fabrico, concentrações certas, existência ou não de encapsulação de ingredientes, entre outras características que determinam a performance de um produto cosmético? E acima de tudo, como o que é que lista de ingredientes me diz acerca do comportamento daquele produto no MEU cabelo? Ambos os métodos guiam as pessoas para escolher produtos mais adequados ao seu tipo de cabelo e couro cabeludo, no entanto, esta escolha por ingredientes não contempla nenhum destes fatores, e existem ingredientes cuja preponderância que cada um destes métodos dão não é assim tão relevante, como já mencionados neste article and in this article. (links) (10)

Difference between conditioner and Co Wash product.

Both of these products have very similar ingredients when looking at the compositions of the formulas, however, the product that you refer to as co wash may have a greater amount of cationic surfactants (or others) compared to the traditional conditioner to achieve a smoother and more effective cleaning, and leave less residue deposit on the scalp.

Can the water pressure in the shower smooth the curls?

When the hair gets wet, the only chemical bonds in the hair that are broken are the ionic, hydrogen and Van der Walls. For the hair to stay straight permanently, disulfide bonds (covalent) would have to be broken to lose its original shape and this is only possible with procedures that change these chemical bonds such as straightening.

If you notice a smoother root or less definition in the root, you can try different finishing techniques (fixing, kneading the hair, dedoliss, etc.) to try to stimulate the definition of curls in that area.

Can brushes straighten curls?

secador. O ato de escovar o cabelo encaracolado quando seco deve ser evitado porque levará a quebra devido à sua curvatura natural e fricção entre o cabelo e o pente/escova que aumenta a eletricidade estática, e por isso quanto menos o fizermos melhor. O cabelo deve ser penteado quando molhado e com condicionador ou máscara de forma a diminuir e quebra ao desembaraçar o cabelo. Outra coisa que pode ajudar é trocar a escova pelo pente (menos cerdas=menos fricção), ou escolher utensílios de dentes mais largos e espaçados.»>O cabelo tem vários tipos de ligação química: covalentes (de dissulfeto), iónicas, hidrogénio e de Van der Walls. Quando o cabelo está molhado, quebram-se a maioria destas ligações à excepção das covalentes, que só são quebradas quando o cabelo é submetido a algum procedimento químico como um alisamento ou descoloração. Para uma escova alisar permanentemente o cabelo, teria que quebrar estas ligações covalentes, o que não acontece. A escova quebra ligações que quando o cabelo volta a ser molhado, estas ligações voltam à sua posição original, tal como esticar o cabelo com secador. O ato de escovar o cabelo encaracolado quando seco deve ser evitado porque levará a quebra devido à sua curvatura natural e fricção entre o cabelo e o pente/escova que aumenta a eletricidade estática, e por isso quanto menos o fizermos melhor. O cabelo deve ser penteado quando molhado e com condicionador ou máscara de forma a diminuir e quebra ao desembaraçar o cabelo. Outra coisa que pode ajudar é trocar a escova pelo pente (menos cerdas=menos fricção), ou escolher utensílios de dentes mais largos e espaçados.


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