The Structure of Hair

You can find better explanations if you look elsewhere on the web, but here is my cliff notes version of the structure of hair.  This is what I think you need to know if you have wavy or curly hair.  I am not a scientist.

The inside of the hair is the cortex.  The cortex is filled with strands of keratin protein.  The proteins form long stretchy rubber band like strands.  These strands give hair it's strength and help support waves and curls.  Fine hair (small diameter of a single hair) is always lacking in protein because the cortex is smaller and can't hold the proper amount of protein easily.  Coarse hair (large diameter of a single hair) has enough protein and and adding more protein (in hair products) can be too much protein.  I talk about this in some of my other posts.


The outer layer of hair is the cuticle.  The cuticle is like scales on fish or shingles on a roof.  It is actually 4-12 layers of fish scales or shingles on a roof (estimates vary and it varies by ethnicity).  The closed cuticle keeps the proper balance of moisture and protein inside the cortex.  The "shingles" laying flat (closed) also reflects light and make hair shiny.  When the cuticle becomes damaged from heat, sun, wind, brushing, dyeing, straightening, perming, etc., you may lose a layer or more of "shingles", the "scales" will open up, or it may loose some individual "shingles".  You may even get a hole in you cuticle.  Through these openings, moisture and maybe some protein will escape.  When this happens, you hair is not as healthy.  Again, more on this later.  The picture (above left) is of damaged hair under a microscope.

If you looked at a cross section of hair, very straight hair would be a perfect circle like looking at the top of a straw.  The curlier hair gets, the more egg shaped the cross section gets. It is like when you squeeze a straw between your fingers.  Kinky curly hair, usually found in African Americans, is almost flat.  Kinky curly hair not only has C shaped bends like curly hair, it also has torsion twists.  Now try to envision shingling these hair shapes.  The straight, circular based straw would have the "shingles" lie flat against the straw.  The flattened oval shaped kinky curly hair with C shaped bends and twists would have shingles that did not lie flat against the base.  The curlier your hair is, the more likely for your "shingles" to be open (a.k.a. porous).  If your hair is porous, you need to replace the moisture that has escaped and close the openings in the cuticle using protein.  (more on this in later posts)  The structure of curly hair causes it to have very different needs then the needs of straight hair. Curly hair must be treated differently to keep it healthy.   I suggest you read this post to understand the difference between kinky and curly hair.  I will also add that people of all ethnicities and curl types may have some kinky hair mixed in with their curly or wavy hair.

For further reading on hair structure see these random links I have bookmarked:
Exploratorium Magazine, Better Hair Through Chemestry 
Black Girl Long Hair- Sturcture of Hair Close Up

Curly Girl Products

I'm going to give you these links, but you have to promise, cross your heart, hope to die that you will double check the ingredients on your bottle.  Product lists are impossible to keep current.  Ingredient lists are always changing.

Going No Poo, Goodbye Shampoo Click the links on the right side for other Curly Girl (CG) products.  This blog includes products that have the ingredient amodimethicone.
Healthy Curls List products that are also protein free.
Curl Girl Journey Has products listed on the left side of the blog.
There is also a list on the Facebook group Wavy Hair Community.  Request an invitation to join.
The Pinerest page of Tiffany Anderson-Taylor/Curl Whisperer/Live Curly Live Free founder/Struts Wife (she has many names) recommends CG products by hair texture.
Most of the products on Wavy Hair Community Product Reviews are CG.


The Wavy Tales has great CG product reviews.  Her post The Conditioner Scales ranks conditioners by how moisturizing they are.  How moisturizing a person finds a conditioner varies from person to person, but the rankings are still very helpful.

So, What Does it All Mean?

The answer to the ultimate question of life, the universe and everything?

If you are not a big geek, ignore that part.  This post explains what all your hair properties mean.  I suggest going on the Wavy Hair Community,  Curl Talk forum on Naturally Curly (or the Long Hair Community for straight hair since Naturally Curly doesn't have a straight hair section) and find people with the same hair properties.  You can see which products and techniques they use for their hair and try them on your hair.

If your hair is wavy check the hair biography file at the Wavy Hair Community (message an administrator to Clijoin, you must be a member to view) or the wavy hair biography thread on NC.com.  Pay more attention to the other properties then you do curl pattern.

Curl Pattern:
Curl pattern is the least important hair property.  In general, the curlier your hair is, the more moisture it needs.  Very curly hair will be dryer, because it has more bends, and the cuticle "shingles" cannot lie flat against the bends in the hair shaft.  When the cuticle "shingles" aren't flat, moisture escapes. People with wavy (type 2) hair often find they need a gel with a harder hold then those with curly hair.  Different styling techniques will work best for each curl pattern.  Styling is probably the biggest difference between different curl patterns.  Also, the straighter your hair, the stronger cleanser you are likely to need.  Straight hair (1's) will likely need at least an occasional sulfate shampoo.  Nearly all wavies (2's) need an occasional non sulfate shampoo (low poo).  Curlies (3's and 4's) are more likely to be able to cowash (conditioner wash) exclusively.

Thickness:
People with thick hair will probably want heavier products to keep their hair from getting too big.  They may also prefer air drying, which produces less volume then diffusing.  On colder days, you can sit under a hard hat dryer to speed things along.
People with thin hair will probably prefer lighter products so their hair does not get weighted down.   They may also prefer diffusing and/or clipping (I'll explain in a later post) as their styling method to add volume.
For more info:  No-poo Jillipoo:  Adjusting the Volume

Texture:
Fine hair:  Fine hair usually does not like a lot of oils, butters, or products that contain them.  Heavy products will be too moisturizing and/or may weigh fine hair down.  Fine hair tends to get over moisturized easily.  Fine hair that is very prone to being weighed down may not like any silicone, even water soluble ones.  People who's hair gets weighed down very easily may find silicones too heavy.  Many fine haired wavies find cowashing weighs their hair down.  Some fine haired wavies cannot cowash and have to use a low poo exclusively.  Fine hair tends to like protein, no matter what the porosity.  Fine hair has a relative small cortex compared to coarse hair, and has a hard time keeping the proper amount of protein inside it.  There is not enough room for protein in the cortex of fine hair, so you have to routinely add more protein.  Products that contain protein and/or protein treatments help keep the proper amount of protein inside the hair's cortex.  Use products that contain protein and/or protein treatments as needed.  Once a week protein treatments are common for fine hair.  You should do protein treatments as often, but only as often as your hair needs them.

Coarse hair:  Usually likes oils and butters and the products that contain them  These products help soften the hair so it bends easier.  Coarse hair tends not to like protein.  (porous, coarse hair will need some protein, but be cautious)  Coarse hair has a large cortex that tends to have plenty of protein naturally.  It doesn't need any additional protein.
More in depth explanation  of "makes hair bend easier" from Science-y Hair Blog.

Medium hair:  Is is in the middle (duh).  It likes some oils, butter, and oil/butter products.  It needs some protein.  Medium hair may like a protein treatment more like once a month to once every few months.  Again, do protein treatments as often as you hair needs them.  When the positive effects of a protein treatment wear off, it is time to do another one.


Porosity:
Porous hair:  Porous hair needs protein.  Protein helps fix the porosity by temporarily filling in the openings and holes in the hair's cuticle. When the protein eventually washes out of your hair, you will need to fill the openings again with more protein. You will want to use protein in you products and/or do protein treatments. If your hair is porous and coarse, use caution because this hair can get too much protein easily.  I've read keratin or silk protein is the easiest for coarse hair to use.  I don't know if that is true or not.  Closing the holes in your cuticle will also help keep moisture from escaping, so treating your hair with protein may help keep your hair moisturized as well.  Experiment with different types of protein to see which type works best.  Your hair may dislike one kind of protein and love another. 

Normal Porosity:  Good for you.  If your hair is fine you will still want protein treatments.  If your hair is medium, you may still want an occasional protein treatment.

Non Porous Hair:  Non porous hair does not need protein because the cuticle lies flat and does not need to be repaired (you still need protein for fine hair).   Non porous hair is very healthy hair in general.  If non porous hair becomes dried out, it hard to get it moisturized again.  It is hard to get moisture back into hair because there are no openings in the cuticle for the moisture to make its way into hair.

Elasticity:
Overly Elastic Hair is a sign hair is over moisturized.  You need to use more protein and use as little conditioner as possible until your hair returns to normal.

Normal Elasticity Hair stretches up to 1/3 of its original length and returns back to its original length.  Good Job.  Carry on.

Low Elasticity Hair can be caused by several things.  Usually it is lack of moisture.  Use moisturizing conditioners, deep treatments, and leave in conditioners.  You may also need protein treatments to shore up the stretchy protein strands in your cortex.

Keep in mind that these are general rules.  Hair is individual.  My hair is very fine, but only follows about half of the general rules for fine hair.  You need to do what works for your individual hair.

If you know your hair likes/needs specific things, this page on Science-y Hair Blog might help you pick products.  

Porosity and Elasticity

When your hair grows out of your head, it is born perfect.  The hair's cuticle lies flat and smooth.  When your hair gets damaged, the cuticle begins to open up.  Hair with a closed cuticle is non porous.  Hair with a cuticle that is open, or missing chunks is porous.  Some hair is naturally susceptible to damage.  Some hair will become porous from sun damage, wind damage, etc.  But...perming, coloring, flat irons, etc. are common causes of porous hair.

Non porous hair (Low porosity)-  Is hard to get wet.  Water runs off it like off a ducks back.  Non porous hair takes a long time to dry (8 hours-ish).  It is hard to get water into the closed cuticle, but once the water is in there, it is locked in tight.  In other words, it is hard to wet and takes a long time to dry.  It will sometimes squeak when you run your hands over dry hair.  Non porous hair is resistant to color, but once is is colored, it won't fade.  It is also resistant to perming or chemical straitening.  These solutions will have to be left on the hair longer for them to be effectively penetrate the closed cuticle.  Low porosity hair is healthy hair.  It is shiny, especially if it is dark.  Hair products seem to sit on top of non porous hair and does not soak in.

Normal porosity hair- Is relatively easy to deal with.  It takes perms and color treatments predictably.  If you always get the color on the box, this is a sign you are normal porosity.  It dries at an average rate (3-4 hours-ish).

Porous hair (High porosity)- Is easy to get wet.  Porous hair dries quickly (1-2 hours-ish) without product.  With conditioner and gel, it may take a long time to dry.  Porous hair soaks up hair products like a sponge.  Porous hair will dye darker then the box (if dying hair a darker color then your natural color).  However, the color will fade quickly.  Perms will take curlier then expected, but then relax quite a bit.  Porous hair is damaged hair, but that doesn't necessarily mean that your were doing terrible things to your hair.  Some hair is just naturally susceptible to damage or has natural kinks that make it porous.  Porous hair tends to be dull.

I should note that the drying times are my guestimations, no actual science involved.  Drying times are based on hair without conditioner or gel.  Products can greatly increase the drying time. Drying times will also be affected by length, thickness, humidity, temperature, etc.

If you read around on NC.com, you may come across the float test.  IMHO, this test is notoriously inaccurate.  I'd call it phoney bologna.  My porous hair literally floated for days.

The Natural Haven:  Junk Science- Hair Porosity Tests/Float or Sink

My porous hair will get wet from the steam when sitting in a hot bath.   My hair will dry in an hour or two without product, but will take all day to dry when I used a heavy conditioner and lots of gel.  I need lots of conditioner and gel for my hair because it soaks it up.  When I dyed my hair darker with a permanent dye, it would dye much darker then the woman on the box.  Then the color would fall right out of my hair.  All the color would be completely gone in three weeks.  When I used to perm my hair (darn 80's) I would look like a poodle the first few days, and then my hair would relax to a normal perm.  The first day people would always say "Oh, you got your hair permed.  It looks....um...nice?"  Then I'd say "Don't worry.  It won't look like this in a few days."  The right hair products have gone a long way to help me with my porous hair.

For more info, I love this curl chemist article.  All of her articles are interesting. You may also like reading The Natural Haven:  Porosity:  Definition and Causes 



ELASTICTY
Take a hair from you head and firmly grasp each end.  Stretch it gently. 

If it breaks, it has low elasticity.

If is stretches up to 1/3 of its length and returns to its normal shape, it has normal elasticity.  Good for you.

If it streeeeeeeetches and does not return to its original shape, it is overly elastic.

Overly elastic hair is a sign of over conditioning (too much moisture). Low elasticity is often a sign of dry hair, but can have more complex causes.  You can do the elasticity test on dry or wet hair.  You may find it easier to take a few shed hairs and sort of twist them together and then pull on the whole wad of hair.  This is an easier way to test my super fine hair.  It is very hard to grasp just one of my hairs.

How to Classify Your Hair With the FIA System

The Fia info was copied from this site.  The info in purple was added by me.

Fia's Hairtyping System

FIRST CLASSIFIER:

The straight ones 
1a - stick straight
1b - straight but with a slight body wave, just enough to add some volume, doesn't look wavy
1c - straight with body wave and one or two visible S-waves (e.g. nape of neck or temples)

The wavy ones
2a - loose, stretched out S-waves throughout the hair  Beachy waves, rock star waves
2b - shorter, more distinct S-waves (similar to waves from braiding damp hair) Princess Hair
2c - distinct S-waves and the odd spiral curl forming here and there A mix of waves and curls and some pieces that have a mix of S and C shapes.  On NC.com this is often referred to as "Wurly" hair.

3) The curly ones 
3a - big, loose spiral curls  Like a telephone cord.  (Anyone else old enough to know what that is?)
3b - bouncy ringlets  Ringlets the size of a pinky finger.
3c - tight corkscrews  Ringlets the size of a pencil or straw.

4) The really curly ones  Common among African Americans.
4a - tightly coiled S-curls 
4b - tightly coiled hair bending in sharp angles (Z-pattern)

SECOND CLASSIFIER
What (most of) your individual strands look like

F - Fine
Thin strands that sometimes are almost translucent when held up to the light. Shed strands can be hard to see even against a contrasting background. Similar to hair found on many people of Scandinavian descent.

You can also try rolling a strand between your thumb and index finger. Fine hair is difficult to feel or it feels like an ultra-fine strand of silk

M - Medium
Strands are neither fine nor coarse. Similar to hair found on many Caucasians.

You can also try rolling a strand between your thumb and index finger. Medium hair feels like a cotton thread. You can feel it, but it isn't stiff or rough. It is neither fine or coarse.

C - Coarse
Thick strands that where shed strands usually are easily identified against most backgrounds. Similar to hair found on many people of Asian or native American descent.

You can also try rolling a strand between your thumb and index finger. Coarse hair feels hard and wiry. As you roll it back and forth, you may actually hear it.


Science-y Hair Blog explains how you can measure your hair will a ruler to tell the texture.  See this link.

THIRD CLASSIFIER
Your overall volume of hair

Put your hair in a ponytail with as much hair as possible in it. Don't bother with the way it looks - the goal is to have most/all of your hair in there. If it means it sits smack dab on top of your head, put it there.

Measure the circumference of the ponytail. If you have bangs and/or you can't get all of your hair in there adjust according to how much of your hair you have measured.

To measure the circumference - take a piece of string, or a soft tape measure (the kind used by dressmakers). Wrap the string or tape measure <i>around</i> your ponytail - just below the elastic you have in to hold the ponytail together. Read the corresponding number from the tape measure, or hold the string at the length you've measured and use a ruler to determine how much it is. The number given is the circumference of your ponytail.

i - thin (less than 2 inches/5 centimeters)
ii - normal (between 2-4 inches or 5-10 centimeters)
iii - thick (more than 4 inches/10 centimeters)

NC.com link with photos of different curl patterns.

Your curl pattern may not fit neatly into only one category.  It is common to see a mix of curl patterns on one head.  This is especially true for wavies.  Some hair just doesn't fit any description.  
Figuring out your hair texture can be tricky as well.  Your hair stylist should  be able to tell you your hair's texture (Kinky or dry hair has been known to throw some stylists.  See below).  If you compare your hair with your friend's hair, this should help you with figuring out your hair's texture.  
Live Curly Live Free has a service where you send in your hair and they tell you your hair's texture, porosity, and elasticity.  The hair analysis I would recommend for a similar price is GoosefootPrints on ETSY.  At GoosefootPrints you get your hair analysis, pictures of your hair under a microscope, and a helpful document that helps you interpret your hair analysis results.  See my sample GoosefootPrints Analysis post. 
If your hair is dry and therefore has a rough feel, you may mistakenly think your hair is coarser then it actually is.  If your hair has some kinky pieces mixed in, this can also make you assess your hair as coarser then it actually is.  Any ethnicity may have kinky hair.  I'm as pale as they come and 40% of my hair has kinks (my GoosefootPrints hair analysis told me this).  This link explains the difference between kinky hair and curly hair with helpful illustrations.  Hair is kinky because of the way it twists (see illustration in link). Another type of kinky hair is where the hair shaft narrows and widens.  I have both of these types of kinks in my hair.

How to Tell if Your Hair is Wavy

Determining if you hair is wavy is not always as cut and dry as you think.  There are lots of people on the 2 boards (a.k.a. wavy board) of the discussion boards of Naturallycurly.com didn't figure out that they had wavy hair until they were older.  I'm one of them.  I thought I had naturally fuzzy hair.  Some people think their hair is naturally scraggly or naturally poofy.  Others thought they had "stupidly straight" hair.  They were sure their hair was straight, it just didn't dry straight when it air dried (a.k.a. wavy).

Wavy hair often needs a good gel and some styling help (scrunching, diffusing, etc.) to reveal it's true form.  In the picture above left, I combed my hair with a wide tooth comb when wet and air dried.  I finger combed a few times as it was drying.  As you can see, there is almost no wave when styled that way.  The picture to the right shows my hair when scrunched and partially dried with a diffuser and no touching as it finished air drying (no curling iron).  The pictures were taken within a month of each other.  As you can see, wavy hair can hide itself from its owner unless you know to look for it.  (My expression in the picture on the left says "I hope my face is actually in the frame and I'm not blinking this time.")

So how do you know if you have wavy hair?  Was your hair curly when you were a baby or toddler?  If yes, then it is probably wavy now.  Here is another easy way to find out.  The next time you take a shower, wash and condition.  Comb your hair using a wide tooth comb with the conditioner in and then rinse.  Add a pea size of conditioner to  wet hair when you are still in the shower.  Scrunch you hair with your hands and look in the mirror.  If your hair looks wavy and has bends, it is wavy.  If the bends fall out and don't want to stay, your hair is straight.

Here is another blog post on this subject.  

Which Ingredients to Aviod With the Curly Girl Method

Snape appears to have some product build up.

With the Curly Girl method, you don't want to put anything in your hair that cannot be removed by a conditioner wash (cowash).  The first and most important thing to avoid is silicones (often referred to as cones in the cyber hair care universe).  Some silicones are O.K. to use.

How to identify a silicone?  Silicones end in -cone, -conol, or -xane.  Don't be fooled by ingredients that end in -one, those are usually preservatives.  Silicones cannot be removed by cowashing, and should be avoided with the Curly Girl (CG) method.

Partially Water Soluble Silicones- Partially water soluble cones are easier to remove.  IMHO, if you use a non sulfate shampoo (low poo) on a regular basis, you don't need to worry so much about partially water soluble silicones. Amodimethicone (A.K.A the A-cone) is the one most commonly seen.  I got a lot of the info in this post from this link.
                                      Amodimethicone
                                      Bis-Hydroxy/Methoxy Amodimethicone
                                      Trimethylsiylamodimethicone
                                      Behenoxy Dimethicone
                                      Stearoxy Dimethicone

Cyclo-silicones-  These evaporate off the hair.  In the process of evaporating, they may cause the cuticle to buckle.  At one point on the message boards of NaturallyCurly.com, people thought the cyclo-silicones were building up.   They weren't actually building up, the change in the way their hair felt was from the buckled cuticle.  The Curl Chemist says a low poo should restore the hair.  See this Curl Chemist article for more info.
                                      Cyclomethicone
                                      Cyclopentasiloxane
                                      Hexamethyldisiloxane (It is a shame this one doesn't also have a Cyclo in the name)


Water Soluble silicones-  These rinse right off of your hair and are allowed in the CG method.  If your hair is fine and very prone to being weighed down, you may still want to avoid them.  Water soluble silicones will weigh down some fine hair.   The first two on the list are the most common.
                       Anything with a PEG- or PPG- in the name.
                       Dimethicone Copolyol
                       Hydrolyzed Wheat Protein Hydroxypropyl Polysiloxane
                       Lauryl Methicone Copolyol
                       Silicone Quaternium 17


Mineral Oil (A.K.A. petrolatum)-  Some people can use this without any problems.  Others, (like me) find it hard to remove.  It makes my hair oily and heavy.  If you are trying a mineral oil containing product, you may want to try it on a small section/curl first.  That way if things go wrong, you don't have a whole greasy head.

Waxes- I'll have to come back when I have a list of ingredients that are waxes.  I believe they are mostly self explanatory.   Waxes can be so hard to remove that even sulfate shampoos can't remove them.  This will vary from person to person.  For some people, they are not difficult to remove.  If you have wax in your hair that is difficult to remove, try doing a diluted apple cider vinegar rinse.  Apple cider vinegar rinses can sometimes remove waxy build up.

Castor Oil, PEG castor oil-  Same ruled apply as for mineral oil.  Straight castor is popular for hair care to add moisture (mostly with type 4 kinky/curly hair).  I've read there is different qualities of castor oil that make a difference.  I don't know too much about using the oil straight.  I'm more familiar with this as an ingredient.  Works for some, hard to remove for others.  PEG castor oil is easier to remove.  My hair hates castor oil in all forms.

Polyquats-  Which polyquats are likely to build up?  Depends on which expert you ask.  All agree that polyquat-4, common in mousse, is easy to remove.  However, there have been several reports on the Wavy Hair Community of build up when using the polyquat-4 containing Aussie Instant Freeze Gel.  So, it looks like polyquat-4 may also cause build up in some people.  These links have more info on polyquats in hair products.  You will need to experiment to find out which polyquats build up on your hair and which are O.K.
Curl Chemist on Polyquats
No-Poo Jillipoo talked to several experts about polyquats.

So, if you avoid everything on this list, does that you will never get build up?  Nope.  Some random things build up for some people.  Jojoba oil and aloe build up for me.  Also cationic conditioners are meant to adsorb (cling) to hair.  They are usually washed off.  But sometimes, some continue to cling to hair and build up.  A low poo will remove this build up.  This link has more on how conditioners can build up.

What does product build up look like?  For me, my hair looks like it has a fake shine.  It looks slightly oily.  It looks somewhat wet when dry.   My hair looks heavy and coated.  My hair will have less bounce.  I believe for some people product build up can cause frizz.

See this link for a list of sulfates to avoid.