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Hair Science ✦

Trusted knowledge for healthier hair.

Evidence-aware guides informed by dermatology research, cosmetic science and professional hair-care knowledge — so you can make more informed choices for your hair.

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The complete Hair Science library, newest topics first within each area.

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Hair Basics

Hair Growth 101

How hair is made, the phases every follicle moves through, and why shedding and breakage are not the same thing.

Well established
Hair Basics

Understanding Your Hair Pattern

Pattern describes the shape your hair takes. It is a useful description, not a complete profile of how your hair behaves.

Supported
Hair Basics

Fine, Medium & Coarse Strands

Strand thickness is the width of a single fibre. It is not the same as how much hair you have.

Well established
Hair Basics

Hair Density Explained

Density counts fibres per area of scalp. It shapes volume and product quantity — not fibre behaviour.

Well established
Hair Basics

Porosity Without the Myths

Porosity describes how the fibre surface interacts with water and product. It is useful context — and it is not diagnosed by floating a hair in a glass.

Supported
Hair Basics

Hair Damage 101

The three damage routes, how weathering accumulates, and the honest difference between cosmetic management and biological repair.

Well established
Hair Basics

Wet Hair & Breakage

Wet hair behaves differently from dry hair. That does not translate into one instruction for everyone.

Supported
Healthy Growth

What Actually Supports Healthy Hair Growth?

Follicular growth, excessive shedding, breakage and length retention have different causes and different answers.

Well established
Healthy Growth

Vitamins & Nutrients for Healthy Hair

An evidence-aware look at protein, iron, zinc, vitamin D, biotin and B12/folate — including why more is not better.

Supported
Healthy Growth

Foods That Support Healthy Hair Growth

Practical food groups behind normal hair biology — without pretending any single food grows hair.

Supported
Healthy Growth

Does Rosemary Help Hair Growth?

Rosemary is one of the most-shared hair remedies online. The published human evidence is far narrower than the conversation around it.

Emerging
Healthy Growth

Growth vs Length Retention

If length has plateaued, retention is usually the variable you can actually move.

Well established
Healthy Growth

Do Protective Styles Make Hair Grow?

Protective styles don't change follicular growth rate. What they can change is how much you handle your hair, for better or worse.

Supported
Healthy Growth

Does Trimming Make Hair Grow Faster?

Cutting the ends cannot change what the follicle does. It can change how much length you keep.

Well established
Ingredients

How to Read an Ingredient List

Ingredient lists are a genuinely useful window into a formula — and they are not the recipe.

Well established
Ingredients

Oils for Your Hair Type

A practical starting-point guide that keeps strand thickness and porosity as two separate questions, because they are.

Supported
Ingredients

Silicones: Good, Bad, or Neither?

Silicones are a broad family of ingredients used for slip and smoothness. Whether they suit you depends on formula, routine and results.

Supported
Ingredients

Sulfates & Cleansing

Cleansing is a spectrum of surfactant strength. The label on the front tells you less than the system inside.

Supported
Ingredients

Proteins & Hair

Protein ingredients can genuinely improve how a damaged fibre behaves — temporarily, and on the surface.

Supported
Ingredients

Humectants

Humectants attract and hold water. What that means for you depends on the whole formula and how you use it.

Supported
Ingredients

Oils & Butters

A reference for common oils and butters, keeping cosmetic conditioning strictly separate from growth claims.

Supported
Ingredients

Clarifying & Buildup

Buildup is an accumulation, not an ingredient. It's the balance between what you deposit and what you remove.

Supported
Scalp Care

Healthy Scalp Basics

The scalp is skin. General skin principles apply — and symptoms are described here, never diagnosed.

Well established
Scalp Care

Dry Scalp vs Dandruff

General education on how these are usually described — not a way to identify what you have.

Supported
Scalp Care

How Often Should You Wash Your Hair?

Wash frequency follows scalp behaviour, product use and lifestyle — a set of variables, not a rule.

Supported
Scalp Care

Scalp Oils: Helpful or Overhyped?

Scalp oiling is a long-standing practice with real comfort benefits and limited evidence for growth claims.

Limited evidence
Scalp Care

Scalp Massage & Hair Growth

The research on massage and hair growth is small and preliminary. That doesn't make it worthless — it makes it emerging.

Limited evidence
Scalp Care

When Hair Loss Isn't a Hair-Care Problem

Some hair changes are outside what any cosmetic product can address. Recognising that early matters.

Well established
Myths & Facts

Myth: Trimming Makes Hair Grow Faster

Trimming can't change growth rate — but it can change how much length you keep.

Not supported
Myths & Facts

Myth: Biotin Grows Everyone's Hair

Biotin deficiency can affect hair. Correcting a deficiency you don't have is a different proposition.

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Myths & Facts

Myth: Protective Styles Always Protect

A style is protective when it reduces manipulation without adding tension. Both halves matter.

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Myths & Facts

Myth: Silicones Are Bad for All Hair

Silicones vary widely, and the buildup question is about your routine as much as the ingredient.

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Myths & Facts

Myth: The Float Test Measures Porosity

The float test is confounded by too many variables to tell you anything reliable.

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Myths & Facts

Myth: Natural Ingredients Are Always Safer

Plant-derived doesn't mean gentle, and synthetic doesn't mean harsh.

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Myths & Facts

Myth: Rosemary Oil Is Proven to Regrow Hair

There is real human research, but it's small, narrow, and not the settled evidence the internet implies.

Not supported
Myths & Facts

Myth: If Braids Hurt, They're Working

Pain is a warning signal, not evidence of a good install.

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Want personalized guidance?

Hair Science teaches the principles. Hairavie applies them to your hair.

Evidence-aware

Based on credible research and professional knowledge.

Credible sources

See the evidence behind important claims.

Always transparent

We show what's known, what's uncertain and where to learn more.

How Hairavie handles evidence

Your pattern isn't your whole hair profile

Pattern, porosity, strand thickness, density, scalp behaviour, chemical history and climate are separate readings — and Hairavie is explicit about which actually influence a Hair Match.

Ingredients aren't good or bad in isolation

A silicone can mean slip, shine and less friction. Whether it suits you depends on the formula and your routine. Hairavie analyses formulas, never fear lists.

Missing data lowers confidence, never invents certainty

Ingredient lists don't reveal concentrations. When formula data is incomplete, Hairavie says so instead of pretending to be sure.

Hairavie provides cosmetic hair-care education only. It does not diagnose or treat medical or scalp conditions. If symptoms persist or you're concerned about hair loss or scalp health, consult a qualified healthcare professional.