Hair conditioners and enriching/nourishing shampoos:
My cosmotologist uncle told me years and years ago that the molecules in hair care products are essentially too big to be absorbed into the hair shaft, and that any positive effect such products have are in terms of appearance rather than structure. I do know that the cuticle of the hair is composed of “scales” that overlap, and that when they’re ruffled in the wrong direction, hair looks less smooth - conditioner basically causes them to all lay in the right direction, yes?
So I was looking at the ingredients on my protein shampoo and “penetrating” conditioner, and there are a lot of salts in them - sodium this and sodium that. Water softeners use salt! So I jumped to this Wild-Assed Guess: these products are softening the water I use to rinse with, and not “nourishing” my hair. Am I right?
Hair is not living tissue anyway, is it? Are there any products that genuinely improve the structure of hair, or are they all cosmetic improvements?
You’re absolutely right. About every three yers Consumer Reports does a study on hair care products, so far results haven’t changes. Its all soap. CU says use what smells good to you, its the only real variable.
The above article debunks your theory of conditioners working by softening the water, as do my own personal experiences. I’ve taken showers in places with very hard water and very soft water and I’ve never had my hair feel as soft as when using a conditioner.
I don’t think that’s a debunk as much as it is a confirmation - no, it doesn’t specifically say it softens the water (a process I’m not really all that clear on anyway) but it does say “surfactants” which seems to mean “on the surface” - further reading says it “adsorbs” which means “adheres” not aBsorbs, which would mean “is taken inside.” So my uncle’s claim that all a conditioner does is make the hair cuticle align to give a smoother feel seems to be backed up here. Also, from my own personal experience I’d say my hair is silkier when I use conditioner than not, no matter what the water, but that softened water alone makes my hair silkier than hard water alone.
So back to the original question - is anything penetrating the hair shaft to make it structurally more sound? And if not, why protein and vitamin additives, and why claims of penetrating the hair shaft?
Nothing’s really penetrating or doing anything at all… but consumers will hear vitamins and think “well, I take vitamins and they make me healthier, and plant vitamins make plants healthier, so putting vitamins on my hair must make it healthier.”
It’s all about what will sell. Put a few scientific words in your product pitch and people will think it’s top-of-the-line.
Oh, god help us. Why do people feel compelled to answer questions they know nothing about?
Shampoos are mostly detergent – specifically, anionic surfactants. These are negatively charged molecules that help to wash oil and grease out of the hair. Why is the negative charge important? Because the hair protein (keratin) has a lot of negative charges sticking out, and negatively-charged detergents rinse right off. Also, the anionic surfactants are cheaper to make, as a rule.
There are also positively-charged, or cationic, surfactants. These are almost always present in hair conditioner; the positive charge binds the molecule to the hair, leaving the shaft a little thicker, and lubricating its surface. This is what we perceive as softer hair. It also fights static electricity, which is why similar chemicals are used in dryer sheets.
Many other chemicals in hair-care products are anionic, and require a positive charge to even the charge balance. This is usually supplied by sodium, which explains the presence of sodium on the label – it’s not softening the water, as I doubt there’s enough there to do the job. There’s absolutely no need to penetrate the hair shaft to be useful. Some molecules (panthenol comes to mind) have enough affinity for hair that they stay behind and glue together split ends.
There are practically no vitamins in any cosmetics - they are present in minute quantities, and they aren’t absorbed by the tissues. Vitamins, furthermore, act in very complex chemical reactions within the body. They don’t have magical powers to repair your hair or skin. Conditioners work essentially the same way that lotions work on the skin - they contain thick, greasy chemicals that bind water to the hair shaft and lubricate the hair, making it softer and more slippery. There’s not much more to it than that. They keep the hair shaft somewhat wetter, making it softer, but they don’t somehow fix damaged hair or “nourish” what is, in fact, dead tissue. The cuticles are like scales, but conditioner isn’t sufficient to cause them to lay down correctly, and the proteins advertised on the bottle have no power to fix damage to the proteinous structure of hair, though they are large molecules that can sit on the surface of the hair strand to bind water to it.
Shampoo removes the natural lubricating oils secreted by your body - and it’s a good thing, too, since they’re strong smelling and will become rancid and attract dirt to the hair if they’re allowed to sit there. Conditioner replaces them, allowing your hair to maintain it’s pleasant texture without having rancid scalp oils sitting on it. The sodium salts present are various chemicals with various purposes - the sodium is just a positive ion that allows the negative ion to be present in the product. Sodium chloride - table salt - is a commonly used thickener in hair products. Many detergents - sodium lauryl sulfate, sodium laureth sulfate, sodium isoethionate, etc. - are sodium salts as well.
“Surfactant” is just a chemical term for detergents. It’s short for “surface-acting agents” or some such, because one of their functions is to reduce the surface tension of water, increasing it’s wetting ability and allowing it to flow into smaller spaces to wash dirt and oil away.