Maybe your hair feels like it’s growing more slowly than it used to. Maybe it doesn’t seem to get any longer, or regrowth feels inconsistent. And naturally, the question becomes: why?
Hair doesn’t grow continuously, and it doesn’t respond to just one factor. Instead, it follows a cycle, influenced by internal balance, scalp health, and how your body prioritises its resources.
Understanding how hair actually grows is often the first step in understanding why it changes.
Stages of hair growth
Hair growth begins beneath the surface of the scalp, within the hair follicles. Each follicle produces a strand of hair by using nutrients, oxygen, and energy supplied through the bloodstream.
But hair doesn’t grow in a constant, uninterrupted way. It follows a natural cycle made up of three main phases:
Growth phase (Anagen)
This is the active phase where hair is continuously growing. It can last anywhere from several years, depending on genetics and individual factors. At any time, about 85% to 90% of the hairs on your head are in the anagen phase.
Transition phase (Catagen)
A short phase where growth slows and the follicle begins to shrink. Only about 1% to 3% of the hairs on your head are in the catagen phase at any given time.
Resting phase (Telogen)
typically lasts around 2 to 3 months. About 9% of your scalp hairs are in this phase.
Hairs don’t grow during the telogen phase, but they don’t usually fall out, either. The telogen phase is also when new hairs start to form in follicles that have just released hairs during the catagen phase.
Shedding phase (Exogen)
essentially an extension of the telogen stage of hair growth. During the exogen phase, hair is shed from the scalp, often helped along by washing and brushing. Losing 50 to 100 hairs per day during the exogen phase is normal.
During the exogen phase, which can last several months, new hairs are growing in the follicles as old hairs fall away.
At any given time, each hair on your head is in a different stage of this cycle. This is why shedding and regrowth are normal and necessary.
Why Hair Growth Isn’t Always Noticeable
Hair growth can sometimes feel slow or inconsistent, even when it’s happening normally.
On average, hair grows around 1 cm per month. But because growth is gradual and because shedding happens alongside it, it’s not always easy to see progress.
In some cases, hair may be growing, but:
- shedding increases at the same time
- breakage prevents length from building
- growth cycles become shorter
- new hair grows finer than before
What Affects Hair Growth?
Internal factors:
Nutrition and nutrient absorption
Hair requires protein, iron, vitamins, and amino acids to grow. Even with a healthy diet, absorption plays a key role.
Hormonal balance
Hormones influence how long hair stays in the growth phase and how follicles behave over time.
Stress levels
Stress can shift hair follicles into a resting phase, leading to increased shedding weeks or months later.
Metabolic balance
Hair growth reflects how the body is functioning overall — including energy availability and internal regulation.
External factors:
Scalp health
A balanced scalp supports better circulation and follicle function.
Product buildup or inflammation
These can interfere with the environment hair needs to grow consistently.
Hair care habits
Excessive heat, tension, or mechanical damage can affect how well hair retains length.
Hair Growth vs Hair Retention
One of the most common misunderstandings is confusing hair growth with hair retention.
Hair may be growing at the root, but if the lengths are breaking or becoming weaker, it can appear as though growth has stopped.
This is why both factors matter:
- growth (what’s happening at the follicle)
- retention (what happens to the hair after it grows)
Healthy hair depends on both working together.
Why Hair Growth Changes Over Time
Hair growth isn’t fixed. It changes with age, hormones, stress levels, and overall health.
You might notice:
- slower growth compared to previous years
- finer strands over time
- longer gaps between noticeable growth
- increased shedding during certain periods
These changes are often gradual and can reflect shifts happening internally rather than something visible on the surface.
Hair rarely changes without a reason.
How Scalp Analysis Can Help
Because so many factors influence hair growth, it’s not always easy to identify the cause of changes on your own.
Scalp analysis allows trichologists to examine follicle density, growth patterns, and scalp condition under magnification. This helps assess how the hair growth cycle is functioning and whether any imbalances may be present.
Rather than guessing, it provides a clearer picture of what’s happening at the root level.
If you’re noticing changes in your hair and want a clearer understanding of what may be influencing it, a more detailed look at your body’s internal balance can be a helpful next step.
The Cell Wellbeing Test offers a personalized insight into nutritional imbalances, sensitivities, and areas your body may need additional support, helping to connect what you’re experiencing externally with what’s happening internally.
Available as an at-home kit or in-clinic assessment, it provides a tailored report designed to support more informed, individualized decisions around your hair and overall well-being.
You can learn more about the test by going to the Clinical Services page.