Every year, around the second half of September, the same thing happens: hair suddenly seems different. Duller, harder to comb, more static, with splitting ends and an amount on the brush that was not there in July. The most common explanation is that the change of season is to blame, and that is not entirely wrong, but it is incomplete. What you see in September is the cumulative result of three months of sun, salt water, chlorine, more frequent washing and hurried blow-drying — plus the natural hair cycle, which in autumn goes through a more visible phase of physiological turnover. The good news is that almost everything that matters right now depends on daily gestures and a handful of product choices, not on extraordinary treatments. This guide explains what really distinguishes one product from another within each family, how a coherent routine is built, which mistakes weigh more than people think, and what makes sense to do now. One necessary clarification: this is about cosmetics and daily care. If you notice significant, persistent or localised hair loss, or scalp discomfort that does not pass, the right place is a dermatologist's office, not the bathroom shelf.
1. How a hair is made, and why it helps to know
No biology lecture is needed, just three facts that explain ninety per cent of the questions.
First: the hair shaft is non-living material. It grows from the follicle, which is alive, but everything you see and touch is an already formed protein structure. This means damaged hair is not repaired: it is managed. Products that promise to "repair" actually do something different and useful — they fill, smooth, coat — but structural damage is not undone. The only definitive repair is a cut.
Second: the surface of the shaft is covered by overlapping cuticles, like roof tiles. When they lie closed and aligned, hair reflects light, slides under the comb and retains water. When they lift — through heat, friction, alkalinity, sun — hair turns dull, rough, tangles and loses moisture. Almost everything we call "damaged hair" is lifted cuticle.
Third: the scalp is skin, and should be treated as such. Many problems attributed to hair — itching, rapid greasiness, dryness — actually concern the skin, and are solved by changing how you wash, not the product you put on the lengths.
The practical consequences
From these three facts follow three rules that apply to every hair type: wash the scalp, treat the length; heat and friction lift the cuticle, so reduce both; and what is already damaged gets cut rather than chased with products.
2. Shampoo: what actually counts
Shampoo is a cleanser, not a treatment. Its job is to remove excess sebum, product residue and particulate from the scalp; everything else — fragrance, promises of volume, visual effects — is secondary. The real differences between one product and another lie in three variables.
Surfactant strength
More aggressive surfactants clean a lot and degrease a lot. They suit scalps that produce plenty of sebum, thick hair, or a summer of layered sun products; they suit fine, coloured or already dry hair badly, because they take away more than necessary. Gentler formulas foam less and this is perceived as "cleaning less", which is almost always false: foam is a pleasant side effect, not a measure of effectiveness.
The stated function
Three broad functions cover almost every real case. The hydrating shampoo, like Farouk Biosilk Hydrating Therapy Shampoo, is the September choice par excellence: it washes without stripping everything, and on a fibre coming off three months of sun and salt it makes a noticeable difference from the second wash. The balanced daily shampoo, like Farouk Chi Infra Shampoo, is the baseline product for people with no particular needs who wash often. The deep cleansing shampoo, like Redken Deep Clean Shampoo, is not a daily product: it is a periodic intervention that removes build-up of silicones, oils, sprays and hard water residue. Used once every two or three weeks it restarts a routine that seemed to have stopped working; used every day it dries.
Washing frequency
This is the variable people change least and that would make the most difference. There is no universally correct frequency: it depends on scalp type, hair thickness, physical activity and water. There are, however, two clear signals. If hair is greasy at the roots within twenty-four hours, a more aggressive product is not the answer — often the opposite is, because a shampoo that degreases too much triggers compensatory production. If instead the ends are dry and the scalp is fine, the problem is not frequency but where the product is applied: shampoo is worked into the scalp, not rubbed along the lengths, which clean themselves with the water running down during the rinse.
3. Conditioner and masks: two products, two jobs
They are often treated as interchangeable and they are not. Conditioner is a finishing product: it works on the surface, closes the cuticle, reduces friction and makes hair combable. It is used at every wash, applied only from mid-length down and rinsed after one or two minutes. A mask is a substance product: it has a higher concentration of conditioning agents and longer contact times, and serves to offset accumulated damage. It is used once or twice a week, not daily, and does not replace conditioner.
There is then a third category, useful above all for curly, wavy or very dry hair: the co-wash, a product that cleanses while conditioning, with very mild surfactants. A detangling co-wash conditioner replaces shampoo for some washes and drastically reduces tangling, which on curls is the main mechanism of breakage. It does not suit everyone: on an oily scalp or very fine hair it tends to weigh things down.
A frequent rinsing mistake
Badly rinsed conditioner weighs hair down and dulls it; conditioner rinsed too quickly does not do its job. The practical rule that works is tactile: rinse until the lengths stay slippery but no longer slide like soap. And the final rinse, where possible, should be with cooler water: this is not an aesthetic ritual, it is that cold water helps the cuticles close again after the heat of the shower.
4. Brushes and combs: the tool that does the most harm or the most good
This is the object with the worst ratio between real importance and attention received. The wrong brush, used daily, does more damage than a year of blow-drying.
The detangler
It is for wet or damp hair, which is at its most fragile because water swells the fibre and makes it elastic but vulnerable. A detangling brush with flexible bristles works by gliding rather than pulling, and should be used starting at the ends and working upwards in sections — never from top to bottom, which is the instinctive gesture and the one that breaks most, because it piles knots onto knots.
The distributing brush
It is for dry hair, and its job is not to detangle but to distribute sebum from root to tip. A brush with dense bristles used in the evening does exactly this, and it is one of the few traditional hair care gestures with solid physical logic behind it: sebum is the fibre's natural conditioner, and without distribution it all stays at the root.
Finishing tools and clips
Minor objects count too. A compact bag brush avoids the makeshift comb at the end of the day, and sectioning clips are not a salon affectation: working in sections while drying reduces total heat exposure time, which is the variable that matters most. Anyone wanting waves without heat can use papillots, which form the curl by setting rather than by temperature.
5. Heat: where the damage really concentrates
Dryers, straighteners and irons are the main culprits for avoidable damage. Not because heat should be eliminated — air-drying completely and often has its own problems, especially in winter — but because almost everyone uses them in a way that multiplies damage without improving the result.
The dryer: distance, power, time
Three rules cover almost everything. Minimum distance is about fifteen centimetres, and the airflow should be directed from root to tip, not against it: blowing the other way lifts the cuticle, and it is why some blow-dries leave hair frizzy however much care is taken. High power helps, because a 2400 W dryer dries in less time at a lower temperature: power is used to shorten exposure, not to raise heat. Time is reduced by blotting well with a towel — blotting, not rubbing — and letting most of the water evaporate before switching on.
Drying and multi-function brushes
These have become the most sensible tool for daily use, because they do in one pass what used to require a dryer and a brush together, reducing overall time. A 3-in-1 styling hot air brush covers the most common case, while an ionic multi-function brush with Coanda technology and interchangeable attachments works at lower temperatures with directed airflow, which is exactly where this category has been heading in recent years.
Straighteners, curlers and the temperature question
The principle is simple: the lowest temperature that achieves the result is always the right one. Fine or light hair needs less heat than thick or dark hair, and the difference is substantial. A ceramic steam straightener works with moisture rather than against it, and a ceramic straightening brush is the correct middle way for anyone wanting less frizz without full straightening: it heats less and for less time, in exchange for a less extreme result. For waves, a wave iron or a curling iron should be used on small sections and with a single pass: going over the same section three times at medium temperature does more damage than one pass at high temperature.
The rule that sums it all up: never heat on wet hair. Water inside the shaft evaporates abruptly and creates microfractures. A straightener is used on completely dry hair, always.
6. Colour: a choice that changes the whole routine
Colouring is not a cosmetic operation like the others: it alters the structure of the fibre and changes the needs of everything else in the routine.
Permanent dyes open the cuticle to deposit pigment inside. They give the most complete coverage, including on grey hair, and last until regrowth. Ammonia-free formulas, like Llongueras Optima Ammonia-Free Dye, work with gentler alkaline agents: the impact on the fibre is smaller and so is the smell, in exchange for grey coverage that is sometimes less complete. Semi-permanents, like Goldwell Colorance Semi-Permanent Dye, deposit without lightening: they are the right choice for reviving, shifting tone or going darker, not for going lighter. Anyone looking for plant-based formulas will find products like Phyto Paris Phytocolor Permanent Dye: it is worth remembering that "plant-derived" does not mean free of possible reactions, and the preliminary test should be done anyway.
Three practical consequences, valid for any colour. First: coloured hair needs gentler shampoos and more frequent masks, because the cuticle has been opened and closed again. Second: colour fades with heat and hot water, so the rules in the previous section count double. Third: after summer, hair lightened by the sun absorbs colour unevenly along lengths and ends, and this is the most frequent reason why a dye done in September does not "take" as it did the year before.
7. What summer really does, and how to fix it
The three summer agents work differently and must be addressed differently.
Sun acts on pigment and on surface proteins: it lightens and makes the fibre more porous. A porous fibre absorbs water quickly and loses it just as quickly, which is why hair in September feels dry even right after washing.
Salt is hygroscopic: it holds water and, drying on the surface, leaves microcrystals that increase friction between hairs. The result is that rough feeling that does not go away with a single wash.
Chlorine is an oxidiser: it acts deeper than people think and is particularly aggressive on coloured or lightened hair, where it can visibly alter tone.
The return protocol
No extraordinary treatment is needed, just a sequence over three or four weeks. Start with one deep cleansing wash, just one, to remove build-up. Then move to a hydrating shampoo as the baseline product. Add a mask twice a week, not daily, because excess conditioner weighs hair down without adding anything. Cut heat by fifty per cent for a few weeks, which is the most effective intervention and costs nothing. And if the ends are split, cut them: a two-centimetre trim does more than any product, because a split end travels up the shaft if it is not stopped.
8. Daily mistakes that weigh more than products
Washing with water that is too hot. It lifts the cuticle, dissolves more sebum than necessary and speeds up colour fading. Lukewarm is enough to clean.
Rubbing with a towel. This is the gesture that generates the most friction in the whole routine, and on wet hair friction breaks. Blot and press, do not rub the lengths.
Combing from top to bottom through knots. It piles tangles towards the ends until they tear. Always start from the bottom.
Tying hair always in the same place and always tightly. Traction breakage is mechanical and progressive, and shows up months later, when it is too late. Varying the height and loosening solves it for free.
Using a straightener on hair that is not fully dry. Said already, but it is the single mistake that does the most structural damage of all.
Changing product every two weeks. A routine should be judged over four to six weeks. Changing sooner means never knowing what worked.
Sleeping with wet hair. Combining a water-swollen fibre with prolonged friction against a pillow is the worst possible combination.
9. Seasonality: why September and October matter
Two things make this window particular. The first is autumn turnover: in autumn a larger share of hairs enters the physiological shedding phase, and the amount on the brush increases without anything having gone wrong. It is a known, temporary and common phenomenon; it becomes something to assess with a professional only if it is marked, prolonged beyond a few weeks or localised in specific spots.
The second is that accumulated damage becomes visible all at once. Hair grows about a centimetre a month: what you see in September along the lengths was exposed all summer. Acting now means December will look different; postponing means finding the same fibre in January, plus the load of dry air from heating.
There is also a practical reason: this is the moment to review the tools. A ten-year-old dryer with a single temperature setting, or a straightener that heats unevenly, does damage every single day. Replacing them matters more than any change of shampoo.
10. Quick questions
How often should hair be washed?
There is no number valid for everyone. The criterion is the scalp: wash when the roots ask for it, and treat the lengths separately. Increasing or decreasing frequency should be done gradually, because sebum production resettles over several weeks.
Can conditioner go on the roots?
Better not. It is not harmful, but it weighs hair down and makes roots greasy faster. Conditioner works where hair is oldest, that is from mid-length down.
Should a mask be used before or after shampoo?
After, on washed and blotted hair: on dripping hair the product dilutes and slides away.
Do straightening brushes damage less than straighteners?
Generally yes, because they work at lower temperatures and without compressing the section between two hot plates. In exchange the result is less defined and less lasting.
Does cutting make hair grow faster?
No: growth depends on the follicle, not the tip. But cutting stops split ends travelling up, and that lets hair keep usable length instead of breaking.
Is a heat protectant necessary?
If you use a straightener or iron regularly, yes: it reduces direct heat transfer. If you only use a dryer at medium temperature and correct distance, the impact is much smaller.
The selection
- Farouk Biosilk Hydrating Therapy Shampoo 355 ml — the baseline product for the weeks after the summer.
- Redken Deep Clean Shampoo 250 ml — one wash every two or three weeks, no more.
- Mielle Detangling Co-Wash 240 ml — for curls and hair that tangles, cleanses while conditioning.
- Steinhart Detangling Brush — on damp hair, always starting from the ends.
- Artero K594 Brush — on dry hair, to distribute sebum from root to tip.
- SwissHome Softly Hair Dryer 2400 W — high power to dry in less time at a lower temperature.
- InnovaGoods Wavify Ionic Multi-Function Hot Air Brush — one pass instead of dryer plus brush.
- InnovaGoods Stemio Ceramic Steam Straightener — works with moisture rather than against it.
- Llongueras Optima Ammonia-Free Dye — permanent, with a smaller impact on the fibre.
Tried, documented, useful: the Dedalshop Hair Products selection promises no transformations, it lines up products that do a weekly, repeated job well. And if one thing were to change after reading this guide, let it be the temperature of the water and of the dryer.