KeraGuides
Hair care, explained properly
36 guides on how hair actually behaves — what the tests measure, what the ingredients do, what the evidence supports and where it runs out. No product rankings, no affiliate links, no miracle claims.
Understanding your hair
Before a routine can be right, the hair has to be read correctly. These are the measurements that matter and the tests that actually work at a bathroom sink.
How to test your hair's porosity (and why the float test is useless)
The float test measures whether your hair has product on it. Three better checks, and what porosity actually changes in a routine.
Density, diameter, volume: the three things people call "thick hair"
How many hairs, how wide each hair, how much space they fill — three separate measurements that people collapse into one word.
What curl-type charts (2A to 4C) get right, and where they stop working
Where the 2A–4C system came from, the one thing it does well, and the four properties that predict your hair's behaviour better than a letter does.
Your scalp is skin, and it is telling you things
Flaking, itch, tightness, oil — what the four scalp signals usually mean, and the point at which a routine stops being the answer.
The hair growth cycle, and why it explains most hair worries
Why you shed about a hundred hairs a day, why your hair stops at a certain length, and why nothing you do shows up for three months.
Shedding or breakage? Tell them apart in thirty seconds
A white bulb means shedding. A tapered end means breakage. The check takes thirty seconds and it decides your entire plan.
Washing and cleansing
Wash day is the single habit with the most leverage in a hair routine, and it is the one most often copied from someone whose scalp is nothing like yours.
Start with the wash guide if you want the routine for your hair type rather than the explanation behind it.
How often should you wash your hair? Ask your scalp, not the internet
Why the "train your scalp to produce less oil" advice fails, and a three-week method for finding the frequency that actually suits you.
You are shampooing the wrong part of your head
Shampoo is a scalp product. The technique — including the second wash and the part everyone misses — takes two minutes to learn.
Hard water and hair: what it does, and what actually helps
What mineral deposits do to a hair fibre, how to tell if hard water is your problem, and which of the fixes are real.
Product buildup: how to tell, how to clear it, how to stop chasing it
How to tell genuine buildup from damage and mineral deposits, what actually removes it, and why clarifying weekly makes things worse.
Conditioner: where it goes, how long it stays, why it stopped working
Why conditioner belongs on soaking-wet hair, ends first, and what to do when it has stopped making any difference.
How to wash straight hair without flattening it
Why straight hair goes flat by lunchtime, and the five-step wash that fixes it — including where the conditioner is allowed to go.
How to wash wavy hair so the waves survive
Wavy hair fails in two directions — dragged straight or crushed by product. The wash day that avoids both.
How to wash curly hair without losing the curl
Sectioning, conditioner-first detangling, and the drying phase where curl definition is actually decided.
How to wash coily hair without stripping or matting it
Why coily hair needs a pre-wash oil, four or more sections, and a sealing step the other types can skip.
Ingredients
Most ingredient advice online is a brand position dressed as chemistry. These pages stick to what a molecule does on a hair fibre, and say when nobody actually knows.
How to read a hair product label in sixty seconds
The four rules — order, the 1% line, the ingredient families, and the marketing words that mean nothing — that make a label readable.
Sulfates: the villain that mostly is not
Sulfates do not cause hair loss and do not strip colour the way you have been told. What they do, and the four cases where avoiding them is sensible.
Silicones, buildup, and the myth about suffocating your hair
Which silicones rinse out, which accumulate, and why the "silicones suffocate your hair" argument does not survive the fact that hair is dead.
Protein and moisture: the balance everyone mentions and few explain
Hair that stretches and stays stretched needs protein. Hair that snaps needs moisture. Getting this backwards is the most common self-inflicted hair problem.
Which hair oils get inside the strand, and which just sit on top
Coconut oil penetrates, most others do not, and the difference decides whether an oil belongs before your wash or after it.
Rosemary oil for hair: what the evidence supports and what it does not
There is one decent trial. Here is what it actually found, what it did not test, and what a reasonable person should conclude.
Damage and repair
Hair is dead protein. That single fact decides what is preventable, what is cosmetic, and what is simply gone — and most damage advice ignores it.
Heat styling by the numbers: which temperatures damage hair
What happens to keratin at each temperature band, why damp hair and a hot iron is the worst combination in hair care, and where to set the dial.
What bleach actually does to a hair strand
Bleach removes pigment, breaks bonds and strips the lipid layer that made hair water-repellent. Two of those three are permanent.
Split ends cannot be healed. Here is what to do instead
Why sealing serums are temporary glue, how far a split travels if left, and the habits that create them.
Why your hair colour fades in three weeks
Water does more damage to your colour than shampoo does. Which pigments fade fastest, and the five changes that actually extend a colour.
Growth and shedding
Shedding worries are mostly timing problems: the hair you lose today was decided months ago. Knowing the delay turns panic into a plan.
Autumn shedding is real, and it has a signature
The research behind autumn shedding, how to tell it from something that needs attention, and why it feels like it came from nowhere.
Stress shedding: the three-month delay that confuses everyone
Why the shedding starts when you feel better, how to find the trigger by looking backwards, and when it stops being self-limiting.
Scalp massage: small evidence, plausible mechanism, no downside
Nine men, four minutes a day, twenty-four weeks. What that study actually showed, and how much weight it can carry.
Postpartum shedding: the timeline nobody warns you about
Why it starts at three months, why it looks so much worse than it is, and the timeline for getting your hair back.
Hair grows about a centimetre a month. What that means for your goals
The real growth rate, why your hair seems stuck at one length, and why retention beats growth as a strategy.
Routines and habits
A routine only works if it survives a bad week. These are the small mechanics — order of operations, friction, sleep, tracking — that decide whether it does.
A curly wash day that works, without the twelve-step routine
The four techniques that produce definition, in order, and why most curly routines fail on weight rather than on products.
Fine hair: how to get volume that lasts past lunchtime
Why fine hair collapses by midday, the products that make it worse, and the techniques that produce lift that lasts.
Detangling: the order of operations that stops breakage
Ends first, upward, with slip — plus the overnight and hair-tie changes that stop most mechanical damage.
How to photograph your hair so progress is actually visible
The five variables that ruin hair comparisons, and a repeatable setup that takes two minutes.
Natural hair growth routines, graded by the evidence behind them
Rosemary oil, scalp massage, coconut oil, caffeine shampoo and five more, each with the evidence stated rather than implied.
A hair care routine that survives a bad week
Eight habits, ranked by how much they change, with the daily, weekly and monthly split — and the four things to drop when the week goes wrong.