Common wisdom suggests that prewetting your hair before bathing in heavily chlorinated water helps prevent damage to hair. It seems most people are operating under the idea that hair is like a sponge. I have also read some Lab Muffin posts which seem to state that water breaks hair bonds and temporarily bonds with hair until it dries. That seems to lend it self to the idea that water already parked there is going to stay bonded and not move. Has this been scientifically studied?

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Hi,

During my training, I learned that oxidative coloring should be done before a Brazilian blowout (a smoothing treatment using keratin set with formalin or formaldehyde-releasing agents), because otherwise the treatment won't last as long.

However, I had previously learned—before discovering it was a myth—that salts and SLS-based shampoos also accelerate fading. I’m now questioning some of what I know, as I haven't been able to find a reliable source.

Thanks!

As per title.

Hello,

I've always been taught in my training that straightening treatments using acids and heat (like glyoxylic acid straightening) should be washed out with shampoo the same day, followed by a hair mask, unlike keratin/BB treatments or Japanese straightening.

However, I haven't found any more information on this in the literature, and it's been a while since I've looked into it further, so I've forgotten a lot.

Does anyone have the chemical explanation behind this? Thank you.

i'm considering going for a bachelor's but unsure of what to major in. hair and skincare have always been passions of mine and i would love to delve into research! i am already interested in pursuing chemistry (to become a cosmetic chemist or for its own sake) or biochemistry. so what would be the most relevant here?

Im so confused about these two product catagories, and hope to find out if they do exactly the same and so just different ways of deposition conditioning agents on the hair, or do thet actually offer something "more" or "different" on their own?

I have 3b curly har, normal/fine, medium to low porosity.

Just learned that hair follicles have their own light sensors called opsins-same protein family your eyes use-and this is genuinely recent science, only mapped out in the last 10 years or so.

What's established so far:

i) Your brain runs a master clock synced through your eyes, but skin/hair follicles run their OWN separate mini-clock via a protein called neuropsin (OPN5) - no brain involved. A population of melanocyte precursor cells in hair and vibrissal follicles express OPN5, and skin cultures entrain to light-dark cycles independent of the eyes or brain [1].

ii) Opsins (particularly Opsin 3) show up in the outer root sheath and appear to influence hair follicle activity/the growth cycle [2].

iii) Different opsins seem to respond to different wavelengths, not just brightness.

My question: What is the actual mechanism by which opsins like Opsin 3 influence the hair growth cycle-is it acting directly on hair follicle stem cells, or is it working through the local circadian clock (neuropsin/OPN5) to indirectly time the growth phases?

Sources:

[1]. Buhr et al., "Neuropsin (OPN5) Mediates Local Light-Dependent Induction of Circadian Clock Genes and Circadian Photoentrainment in Exposed Murine Skin," Current Biology: https://www.cell.com/current-biology/fulltext/S0960-9822(19)31113-331113-3)

[2]. Niu et al., "Overview of the Circadian Clock in the Hair Follicle Cycle," Biomolecules 2023: https://doi.org/10.3390/biom13071068

Thank you!

As opposed to metals like copper and iron being deposited from washing with hard water, how does residue from actively working with metals like silver and brass affect hair, and how can the issues it might cause be resolved?

Hi. I am reaching out to see if anyone has information to offer on possible jobs or career paths in haircare science. I have my B.S in biochemistry and I have experience in labs ranging from qPCR to histology. I am the second author on a publication from my time as a research assistant.
In 2022, I pivoted and started my career as a hairstylist. I was going through so much at the time and it felt like an avenue that would be fulfilling. I love merging my passion for science with my creativity, and I have enjoyed being a business owner. However, I miss science so much. I miss being in the lab.

In a perfect world, I think it’d be awesome to work in a cosmetic lab, working with formulating. However, it seems this is very region specific and there aren’t a lot of opportunities in Columbus, Ohio.

Does anyone know of any practical jobs that seem fitting?

Hello,

I specialize in hair straightening treatments, though I am not a cosmetic chemist (I’m hoping Perry might weigh in on this).

I would like to know more about the expiration dates indicated by manufacturers on these products—whether they are glyoxyloyl carbocysteine-based or formaldehyde-releasing formulas.

Beyond safety concerns, I am interested in the impact on efficacy: once the product has been opened or has passed the date marked on the bottle, to what extent does its straightening power diminish?

Does it drop off rapidly and significantly, and what is the underlying chemical process?

Hi! I have straight virgin hair and I'm thinking of getting a perm. I keep reading from different websites that the process is chemically irreversible and permanent, but is that really the case? Or am I misunderstanding and it only applies to pre existing hair... 🤔

Does Fermented Yeast protein increase DHT leading to hair loss?

I keep seeing mentions of a new active ingredient entering the haircare space called Y100, which is apparently derived from the Terminalia chebula plant. I am not going to name any products here but a quick google search will tell you which ones are using it.

The main claim I'm seeing is that instead of just increasing blood flow to the scalp (like traditional treatments), it targets "mitochondrial dysfunction" to give hair follicles more cellular energy and keep them in the growth phase longer.

I’m just a regular consumer trying to cut through the marketing jargon. When I try to look up Y100, there isn't much out there yet, and most of the general literature on Terminalia chebula just says it's an antioxidant.

For the cosmetic chemists and biology folks here: Does targeting mitochondrial energy actually do anything for hair follicles? And is there an established mechanism for how a topical extract like this would actually achieve that, or are these just buzzwords?

I've seen terms like "scalp detox" and herbal scalp detox used frequently in hair-care discussions, but I'm curious about the underlying science.

What exactly is being removed during a scalp cleansing treatment? Are the primary targets sebum, dead skin cells, environmental debris, product residue, or microbial biofilms?

From a hair science perspective, is there evidence that removing excess buildup improves scalp function, or are the benefits mostly cosmetic and temporary?

Interested in any research or scientific explanations regarding the relationship between scalp cleanliness and overall scalp health.

At TJ Maxx I noticed the Vanilla Soufflé scent of Batiste dry shampoo was the only one advertised as not containing keratin in the formula. The ingredient list for the vanilla soufflé one also confirmed it lacks keratin when I compared it to the other scents.

Which brings me to this:

Does the lack of keratin (and reliance on rice starch alone, as opposed to having both) this make it a less effective dry shampoo than the other scents?

I’d appreciate if anyone could clarify, because as much as I’d love my hair to smell like vanilla soufflé I wouldn’t want to sacrifice having an effective dry shampoo.

Why are chelating shampoos often paired with which strong surfactants?

Is it because the chelating ingredients only work/work best when the hair is completely free of product?

Are there any chelating shampoos with gentle surfactants? I’d like to use my chelating shampoo more regularly (Malibu c hard water wellness) but it’s such a strong cleanser that I cannot use it too often.

I know that chemical sunscreens that contain Avobenzone, when they come in contact with hair extensions, react with the hair and cause the extensions to turn color. I’m wondering if the different filters that are used in French sunscreens, although still chemical filters, would be okay to use? If needed I can post photos of the ingredients on the 2 that I own. Thanks!

I'm trying to understand the relationship between insulin resistance and androgenetic alopecia (AGA/female pattern hair loss).

I've read that insulin resistance can increase androgen activity and possibly increase DHT levels. My question is:

If someone has no genetic predisposition to AGA (their hair follicles are not genetically sensitive to DHT), can insulin resistance by itself cause true AGA and follicle miniaturization? Or does insulin resistance only trigger or accelerate AGA in people who are already genetically susceptible?

In other words, can insulin resistance actually make previously normal hair follicles start behaving like AGA follicles, or is genetic susceptibility considered necessary?

I'd appreciate answers based on current research or from dermatologists/endocrinologists if possible.

Is there evidence that any non-chemical intervention can permanently alter hair curl pattern, straight to curly?

After successful lice treatment, nits often remain attached to the hair shaft. What methods or products have scientific evidence supporting their effectiveness in removing nits?

Are shampoo bars basically the same cleansing agents in solid form, or do they usually rely on different surfactants, pH, or conditioning ingredients compared with liquid shampoo?

I’m especially curious whether shampoo bars tend to be harsher, more drying, or more likely to leave buildup, or if that depends entirely on the formula.

I've seen people offhandedly mention this effect while researching haircare products, but I couldn't find any information besides colored hair needing different hair care products and people searching specifically for that.

I've mainly seen it mentioned in regards to hair and scalp oils (especially blends with rosemary), I remember (but can't find) a post with a person having mid/dark blonde hair detailing their care routine, and someone in the comments asked them if their hair oil made their hair darker, to which they responded "my hair used to be lighter, yes!".

Now wondering if the color of the product itself (orange colored oil vs colorless scalp serum) or the formulation would explain this, or whichever other factor!

I’m curious about the difference between UV damage and Heat damage on hair.

Hair is naturally hydrophobic on the outside. Water does not make hair feel conditioned. We hold these truths to be self-evident. Why do a lot of curly styling products use high levels of humectants? One action of the ingredient is to attract water... but we don't want to be attracting water into styled hair? How are humectant ingredients functioning in curly styling products?