Every hair on your head is moving through a three-stage cycle: anagen (growing, for years), catagen (a brief transition, a couple of weeks) and telogen (resting, then shedding, a few months). At any moment, around 90% of your hair is growing while the rest rests and sheds, which is why losing 50 to 100 hairs a day is completely normal. Understanding this cycle explains almost everything about hair, from why it has a maximum length to why stress makes it shed months later. Here is the cycle, stage by stage.

Stage 1: The anagen phase (growth)

This is the active phase, where the follicle continuously produces new cells that push the hair shaft longer, at roughly a centimetre a month. It is also the marathon stage: anagen typically lasts 2 to 7 years, and how long yours lasts is mostly genetic. That duration is why some people can grow waist-length hair and others cannot, the longer your follicles stay in anagen, the longer your hair can get before it cycles out. Around 85 to 90% of your hair is in anagen right now.

Stage 2: The catagen phase (transition)

A short handover lasting about two weeks. The follicle shrinks, growth stops, and the hair detaches from its blood supply, becoming a "club hair" that sits in place while the follicle prepares to rest. Only around 1% of hairs are in catagen at any time.

Stage 3: The telogen phase (rest and shed)

The follicle rests for around three months while the club hair stays loosely anchored. At the end of telogen the old hair sheds, often as you wash or brush, and a fresh anagen hair begins growing in its place. About 9 to 14% of your hair is in telogen, which is exactly where the normal 50 to 100 daily shed hairs come from.

The cycle at a glance

What can disrupt the cycle?

• Stress, illness and shock can push extra follicles into telogen early, causing the delayed shedding of telogen effluvium.
• Hormones, from childbirth to menopause and thyroid conditions, shift how long follicles spend in each phase.
• Androgens gradually shorten anagen in sensitive follicles, the mechanism of pattern thinning.
• Age naturally shortens anagen, so hair grows finer and shorter over the decades.
• Nutrition: follicles are among the body's most energy-hungry tissues, protein, iron, zinc and B vitamins keep the cycle fed.

How to support a healthy cycle

You cannot change your genetics, but you can give every phase good conditions: eat well, manage stress, be gentle with the hair you have, and keep your scalp clean and comfortable, a sulphate-free wash like our Grow Me shampoo with biotin, caffeine and rosemary is a kind foundation, with a weekly Masque Me mask to protect strands through their long anagen years. If a medical condition or treatment is affecting your hair, your GP's plan comes first.

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Frequently asked questions

What are the 3 stages of hair growth?

Anagen (active growth, years), catagen (transition, about two weeks) and telogen (rest and shedding, about three months).

How fast does hair grow?

Roughly 1 cm, about half an inch, per month on average, varying with genetics, age and health.

Why can't my hair grow past a certain length?

Your genetically-set anagen duration caps it: hair can only grow for as long as its follicle stays in the growth phase.

How many hairs is it normal to shed daily?

50 to 100, these are telogen hairs finishing their cycle, immediately replaced by new anagen growth.

Why did my hair shed months after a stressful event?

Stress pushes follicles into telogen early, and telogen lasts about three months, so the shed shows up on that delay.

Can products speed up the hair cycle?

No product changes the biology of the cycle. Good care protects hair through its phases so more of it reaches its potential length.

The hair cycle is the key that unlocks the rest: anagen sets your length, telogen explains your shedding, and disruptions explain most hair scares. To go deeper, read what causes telogen effluvium and how hair grows.