How can you take care of your hair if you don't even know what stage of life it's in? Your hair is not frozen in time. It lives, evolves and reacts. What you find on your brush, your pillow or even the tiles in your shower? It's all the result of a precise biological cycle, all too often ignored. At any given moment, every strand of hair on your scalp is growing, pausing, falling out or in transition to one of these states.
Understanding the hair growth cycle means you can stop doing your hair care blindly and start focusing on what really works.
Inside your hair cycle—the 4 phases that shape your hair
Your hair cycle moves through four distinct phases, each with a specific role that shapes how your hair grows, rests, and sheds over time. Understanding how this cycle works begins with the first phase, where your hair remains in active growth for the longest part of its cycle:
The anagen phase
This is where it all comes together. The anagen phase is when your hair actively grows. It is rooted, nourished, and alive. This phase can last anywhere from two to seven years, and its duration directly shapes how much your hair can grow over time.
On average, around 85% of the hair on your scalp is in this phase. That reflects a stable internal environment. Your body is adequately nourished, your hormone levels remain stable, and your scalp is not dealing with ongoing stress or inflammation.
This phase does not last the same amount of time for everyone. Several factors influence it, including genetics, hormones, ethnic background, and diet. Each of these elements affects how long your hair stays in active growth before moving to the next stage.
Take a simple example. An iron deficiency can slow down growth and weaken the roots. In some cases, it can shorten this phase altogether. When you correct the deficiency through diet or supplementation, your follicle can gradually return to normal function.
The same logic applies to topical hair care. The condition of your scalp and hair follicles also influences how your hair grows over time. Ingredients such as caffeine, ginseng, niacinamide, and peptides can support a longer growth phase when used consistently.
The catagen phase
The catagen phase lasts around two to three weeks. It is brief, but it plays a key role in the hair cycle. During this time, your hair gradually detaches from its blood supply and stops growing. Your hair follicle begins to shrink, its activity slows, and your scalp moves into a steadier state. At any given moment, about 1% of your hair is in this phase.
You may not even be aware that this stage exists. Still, it tends to raise questions when you notice more hair than usual. A few strands fall, and you start wondering whether something has changed in your routine. In most cases, nothing is wrong. These hairs have simply reached the end of their cycle and are moving on, exactly as they should.
The telogen phase
The telogen phase is often associated with chronic hair loss, although it corresponds to a resting period in the cycle. During this time, your hair stops growing and remains anchored in the hair follicle while activity slows down. It stays in place until a new cycle begins.
At any given moment, around 10 to 15% of your hair is in this phase. This proportion can increase when your body goes through a period of stress or imbalance, such as intense fatigue, post-partum recovery, illness, or emotional strain. This shift is known as telogen effluvium. During this period, hormonal and metabolic changes can move a larger proportion of your hair into the resting phase.
What helps here is consistency and a routine that stays simple and stable over time. Gentle hair care, regular scalp massages with oils such as jojoba, and a calmer routine altogether support a more stable environment. Over time, this allows your hair cycle to return to its natural rhythm.
The exogen phase
The exogen phase marks the final step of the hair cycle, when your hair is released from the follicle and falls out. On average, you lose between 50 and 150 hairs a day, which reflects a normal renewal process within your scalp.
When the amount of hair shed exceeds this usual range and begins to affect your overall density, with larger amounts falling out and a visible loss of volume over time, the shedding goes beyond the typical exogen phase and may indicate a disruption in your hair cycle that requires closer attention.
BHC Takeaway
Most of your hair remains in the anagen phase, where hair growth depends on how well your body supports it through nutrition, hormonal balance, and overall health.Short transitional stages such as catagen and telogen regulate your hair cycle, guiding your hair through transition and maintaining it in a resting state until it is released from the hair follicle. Finally, daily hair fall remains part of a normal renewal cycle, while noticeable changes in volume or density signal a shift that may require closer attention.
What can disrupt your hair cycle?
The way your hair grows, sheds, and renews itself is constantly influenced by what happens within your body, the environment surrounding your scalp, and certain conditions that directly affect the hair follicle. Looking at these influences more closely helps explain why your hair cycle can change over time, sometimes gradually and sometimes quite suddenly.
Inside your body—the conditions that influence your hair growth
When your body goes through imbalance, your hair reflects it.
Hormonal fluctuations, whether linked to thyroid dysfunction or conditions such as PCOS, can alter the rhythm of your hair cycle by shortening the anagen phase and increasing the proportion of hair entering telogen.
Nutritional deficiencies, including low levels of iron, protein, or zinc, affect this process in a similar way by limiting the resources your hair relies on to grow and maintain itself.
Stress also plays a direct role, as periods of sustained stress are commonly associated with increased hair shedding, particularly through telogen effluvium.
Daily habits and environmental exposure
External aggressors place continuous strain on your hair and scalp. Chemical straightening, frequent heat styling, or bleaching expose your follicles to repeated stress, gradually affecting their ability to function properly.
Environmental factors such as pollution and UV exposure add to this pressure, while certain cleansing products with harsh formulations can further weaken your scalp’s protective barrier. Over time, your daily habits shape how well your hair withstands these conditions and maintains its balance.
Hair cycle disorders
- Androgenetic alopecia gradually shortens the anagen phase and miniaturizes hair follicles over time. Changes often appear slowly at first, which is why early intervention tends to be more effective.
- Telogen effluvium does not permanently damage your hair follicle, but triggers increased shedding following a physical or emotional stressor.
- Alopecia areata is the most unpredictable of the three, it can completely halt the hair cycle in certain areas of the scalp due to an autoimmune dysfunction
BHC Takeaway
Changes in your hair cycle rarely come from a single source. The condition of your body, the environment surrounding your scalp, and certain hair disorders can each influence how your hair grows, rests, and sheds throughout its cycle.
How to support a healthy hair cycle?
Once you understand how the hair cycle works, the next step is learning what helps it function under the right conditions. From nutrition and scalp care to targeted treatments, several approaches can support the different phases of the cycle.
Nutrition, lifestyle, and hair health
You can’t compensate for a nutritional deficiency simply by applying a hair mask. Your hair depends on the same foundations that support the rest of your body. A consistent intake of protein, iron, omega-3 fatty acids, and nutrients such as biotin helps maintain a healthier environment for growth over time. Eggs, lentils, oily fish, flaxseeds, and green vegetables all contribute to this balance when they are part of your routine rather than occasional additions.
Sleep, hydration, and stress management also influence how your hair cycle functions from one phase to another. When deficiencies are identified, supplementation may help restore what your body lacks, particularly when guided by medical advice and appropriate testing.
Scalp care rituals
A healthier hair cycle also depends on the condition of your scalp. Gentle exfoliation can help remove buildup around the follicles, while ingredients such as peptides or caffeine are commonly used to support scalp activity and improve the overall environment surrounding the follicle. Daily care matters just as much as treatment itself, especially when your routine remains stable and adapted to your scalp’s needs.
The tools you use also shape how your hair responds over time. Softer brushes and styling habits that minimize pulling, friction, and tension help protect both your scalp and hair fiber, particularly when your hair is already fragile or shedding more than usual.
Some situations require more targeted support. Treatments such as microneedling combined with PRP or low-level light therapy are increasingly used to support hair growth and stimulate follicles, particularly during the earlier stages of hair loss. Their effectiveness nevertheless depends on the underlying cause, the condition of the scalp, and the consistency of treatment over time.
A proper diagnosis remains essential when shedding becomes persistent, sudden, or difficult to explain. A dermatologist or certified trichologist can help you identify what is affecting your hair cycle and determine whether the issue relates to hormones, inflammation, nutritional deficiencies, or another underlying condition.
Our final takeaway
Your hair moves through a continuous cycle of growth, transition, rest, and shedding, and each phase gradually shapes the way your hair looks and responds over time. When you start noticing more shedding, slower regrowth, or visible changes in density, these shifts often trace back to what is happening within that cycle, whether your body is dealing with stress, hormonal fluctuations, nutritional deficiencies, or repeated strain on the scalp. Supporting a healthier hair cycle, therefore, comes down to the way you care for your scalp, the habits you maintain daily, and the overall condition in which your hair is expected to grow.
