How does the hair growth cycle work? A Guide To The Hair Growth Cycle

Did you know that healthy human hair typically grows at a rate of about 0.35mm each day? Over the course of a month, this totals around half an inch. And in a year? Approximately six6 inches. 

While the rate of hair growth differs for everyone –— with some people experiencing accelerated rates of growth,,  and others with little to no growth at all — the way in which hair grows is the same for everybody. Regardless of hair type, style, or genetics, hair grows in line with the four stages of growth in the hair cycle. 

Read on to find out more about the hair growth cycle of hair and how hair is produced. 

How does hair grow?

Before we get into the hair-raising details, let’s first discuss the different parts of what we know as ‘hair’. 

Taking the hair on your head as an example –— under the skin of the scalp are  things called hair follicles or ‘roots’.  and these are what your hair grows out of these.  

These follicles have direct contact with the bloodstream, from which the hair is ‘fed’. This point of contact allows the nutrients and minerals to pass through the bloodstream into the hair to give it the nourishment it needs to grow.

The hair growth stages, four cycles of hair growth

From the moment your hair starts to grow, to when it falls out, it passes through four stages: 

1. Anagen 
2. Catagen 
3. Telogen 
4. Exogen 

Each and every hair on your head is at a different stage in its growth cycle. Let’s look at each of these stages individually. 

1. Anagen phase

The anagen phase –— also known as the ‘growth’ phase –— and involves, you've guessed it, a lot of growth. During this time, the cells in your hair follicles experience high levels of activity and divide rapidly, causing new hair to be formed.  

It is during the anagen phase that each strand of hair will experiences the most growth. Usually, this lasts for anything between 3 to 5three to five years. So, when using the figures from the start of this blog, full-length hair (if not cut) could grow between 18 and 30 inches in that time!  

There are a variety of factors that affect the anagen phase, however. For example, people of Asian descent tend to have a longer anagen phase (up to seven7 years). 

Why does hair stop growing when you get older? 

Over time, the length of the anagen phase decreases. This is why hair growth is rapid in younger people, but in elderly people, hair growth is slower as the hair becomes weaker and thinner after each cycle.

2. Catagen phase

Up next is the Catagen phase. This period of time stage represents a period of ‘rest’ for your hair after undergoing all that growth activity. The catagen phase is usually very short (around 10 days) and signals the end of active hair growth. About 3% of all hairs on your head are in the catagen phase at any given time.

During this transitional phase, the hairs that were previously growing using nutrients from the blood supply (via the hair follicle) are now cut off — not literally!.  

The blood supply to these hairs and their follicles is stopped.  

3. Telogen phase

The telogen phase represents yet another period of rest for your hair and its follicles. Where the catagen phase sees the blood supply no longer reaching these hairs, the telogen phase is the period of time period where the hairs sit in place without said blood supply.

Roughly 10-15% of your hairs are in this state at once, sitting in place without actively growing. This is 10ten times longer than the catagen phase and can last up to 100 days (or three3 months). 

4. Exogen phase

Lastly, there is the exogen phase. This is also known as the ‘Shedding’ shedding’ phase as many hairs are lost at this point. Here, you may notice a greater amount of hair loss – possibly losing between 50-100 hairs a day – when brushing or washing your hair.

This stage usually lasts between two to five months –— but don’t worry, new hair is constantly growing. After older hairs are released from the follicle, the whole process can begin again! 

You can find out more about the elements that feed into the hair growth cycle over on our How It Works page!

Look after your hair at all stages in the cycle

Whether your hair is in the anagen or exogen phase, it all still needs protecting. With Viviscal’s hair vitamins for men and women –— and our range of shampoos and conditioners –— it has never been easier to help give your hair the nourishment it needs to grow healthily from the inside out.  

If you have any more questions about the hair growth cycle, contact our team of experts today.