Sunday, 16 November 2014

A thought on sebum

It seems to be commonly accepted knowledge in the longhair circuit that sebum comes in two different forms: A liquid oil and a harder wax, and that each individual scalp has its own ratio of those two.

But lately I’ve been wondering:
What if the two forms are really just one? I mean, oil or milk or any other liquid for the matter can be split in firm and liquid components if you filter it finely enough.

Maybe the form of sebum you see the most is depending on how porous and absorbing your hair is.
If your hair is very porous, maybe it will easily absorb the liquid components of the sebum and leave you with the waxy kind?

And if your hair doesn’t absorb well, maybe the liquid oil will seem more dominant because the waxy kind doesn’t show up until you “drain” the liquid from the sebum?

What do you all think?


  1. From my understanding when I was researching/understanding my own scalp issues, sebum/oil from the scalp various from person to person in how much is produced. From my understanding, over production of sebum is the cause of dandruff: But it has different levels. The waxy, wet kind and the dry, crusty kind. the dry, crusty kind is a fungus that has developed as a result of the sebum/reaction (scientists aren't quite sure why this happens), whereas mild/moderate dandruff is just an over production of oil and the skin cells can't shed fast enough. I've had very, very bad, painful dandruff that boardered on psoriasis. That was horrid. The dandruff was white/silvery and crusty, itched like mad, but when you picked away at it, it bled and the skin beneath was very, very inflamed. I was shedding hair in fist fulls(it was disgusting, thank god I have a lot of hair) This was in my late 20s after a very, very difficult time. Nothing relieved the pain/itching. I had actually no oil from my scalp which baffled me. My doctor said it was completely stress based and gave me drops for the itching/scalp. It was steroid based so I didn't use a lot--in fact, 2 drops in affected areas (it wasn't my whole scalp) and whammo---went away! That shocked me. I had a similar reaction, though not as severe, 2 years ago due to a hormonal shift. My scalp had reduced in oil production which allowed me to extend my shampooing to three times a week. Now? I'm back to daily because I'm producing more oil and the itching is horrific! I'm back to how I was as a teen, though the grease isn't nearly as bad, it's back and I think my scalp didn't react well. Thankfully a salon shampoo was able to help ease the discomfort and got my scalp back to normal level. I was trying to find a PH balanced shampoo (I miss Timotei because of that!!), but good luck!

    So, my round about answer is, I don't think the scalp oil is different, but rather how much is produced and how the scalp reacts to the production. Waxy build up would just be oil and skin cells. Crusty build up may be more a fungus or reaction from the scalp due to that build up. :)

  2. I'll add my pet theory about this, it's a mixture of your's, Ida, and Darkhorse's:

    I've seborrheic eczema and when I don't wash daily, I get a waxy, crusty buildup, that yellowish. My skin itches like crazy and it will bleed quite easily.
    Other parts of my scalp that aren't affected will just look oily and those parts have oily looking hair has well. I could live with oily hail, but the affected parts make my hair look waxy, flakey and oily, a really unsightly combo.
    So, from my understanding of my scalp, there is this oily sebum and the waxy, yellowish stuff. I've never had the "normal waxy" sebum, but that might be due to my daily washing and lack of actual build-up of skin cells. My uneducated guess (and I'm assuming this for people who don't wash daily) would be, that sebum come as an oil and porous hair will absorb a bit of it, until saturated. You're left with the waxy kind that has skin cells in it. Less porous hair probably will not absorb as much of the oily sebum, so the hair will look greasy. After not washing for a few days, and the skin cells mixing with it, it becomes more waxy.
    And then there's the yellowish stuff people with excema get: As Darkhorse said, it's a fungus that causes it. A common therapy for it is to wash daily, as the lesser amount of sebum will inhibit the fungus' growth.
    So, to sum up my rant, my guess is that it's all oily in the beginning, but hair texture, shedding of skin cells and washing rhythm affect the consistency of the sebum.
    And now I'll shut up. I'm sorry for the probably quite incoherent text above, I'm writing my master's thesis, need to rewrite it from the beginning actually, thanks to my superb supervisor. Since it is due in 2 month and I have like two pages, I'm passing my time reading here. I think it's a good plan.

    1. I think also, from my understanding, those who have problems with eczema (I have that too) and dandruff, it's an over production of oil/sebum which is why we have to wash daily. The itching is what kills me---I will scratch my scalp until it bleeds so I went back to washing daily--I mix my shampoos up, but head and shoulders seems to work best to keep the fungus at bay. I also do a clarifying once a week and daily conditioning. So far, this works but I also know that hormones are really affecting my scalp/oil production. I've had an oily scalp my whole life--as a kid, I would wash every other day and didn't find dandruff an issue. It only got bad once I noticed changes in my hormones (late 20s). However, before I hit puberty, I had bad dandruff, but more the waxy kind--not the crusty. That came due to stress--so, then I wonder, can your stress level change the production of sebum and cause the reactions we have? I do remember the pharmacist told me when you use medicated shampoo (Nizoral was what I used at a mid way bad time) and it worked for visible flakes, but what people don't know is that dandruff or the fungus that causes it is actually under the skin of the scalp. That's why you need to leave the shampoo on the scalp for 5 minutes. The itching is the medication working (like a wound healing) Lord of life, it drove me nuts! I washed once with that and bam, problem solved. Scalp was happy.

      I've also used salon dandruff shampoos and the AG one was very nice--gentle on the hair, but worked to manage dandruff. It didn't prevent it though (ie: Not using it and having a flare, it wouldn't work to stop the itching etc)

      So, for those with excess oil production, washing daily helps control that and the skin shed, which I think it possibly where we get the variation of waxy vs crusty. Perhaps waxy is new and crusty is old/dried??