Summary
-
Hair grows in 4 phases: The anagen (growth), catagen (transition), telogen (resting), and exogen (shedding) phases. Disruptions to this cycle can lead to thinning or shedding.
-
Hormonal imbalances, genetics, stress, nutritional deficiencies, and scalp inflammation are key factors that can disrupt the hair growth cycle and lead to hair loss.
-
Temporary hair loss due to shedding is common and often recovers with proper care. Permanent hair loss is rare and typically caused by severe allergic reactions or follicle damage.
-
Minoxidil, finasteride, laser therapies, and hair transplants are effective treatments for restoring healthy hair growth.
-
Scalp health plays a vital role in hair health. Using treatments that reduce inflammation and nourish the scalp helps maintain healthy follicles for better hair growth.
- BosleyMD offers personalized consultations, FDA-approved treatments, and hair restoration solutions to address hair loss effectively.
Understanding the natural cycle of hair growth is essential to maintaining strong, healthy hair. Each strand of hair undergoes a specific series of phases, and when any of these phases are disrupted, it can lead to hair thinning or shedding. It’s normal to lose about 50–100 hairs a day, but excessive shedding or a noticeable slowdown in hair regrowth may signal something isn’t right.
The 4 Stages of the Hair Growth Cycle
Hair doesn’t grow all at once; instead, it goes through a cycle that includes four distinct phases. These phases are essential for the health and longevity of your hair. Let’s break them down:
1. Anagen Phase (Growth)
-
Duration: 2–6 years
-
Activity: During this phase, hair follicles are actively working to produce new hair shafts.
-
Growth Rate: Hair grows approximately half an inch per month during this phase.
-
Percentage of Follicles: Around 85–90% of your hair is in the anagen phase at any given time.
The anagen phase is when your hair is actively growing. The longer your hair stays in this phase, the longer it can grow. In fact, if you’re growing your hair long, this is the phase you want to last as long as possible. It’s essential for length, and its duration can vary depending on genetics and health factors.
2. Catagen Phase (Transition)
-
Duration: 1–2 weeks
-
Activity: After years of steady growth, the hair follicle enters a brief resting phase where the growth process stops. The hair follicle shrinks and detaches from its blood supply during this transition. This sets the stage for the next phase, where the follicle will reset.
Although this phase is relatively short, it’s vital for the hair follicle to transition properly into the resting stage. It’s like a brief break before your hair moves into a dormant state.
3. Telogen Phase (Resting)
-
Duration: ~3 months
-
Activity: In this phase, hair follicles are dormant. The hair stays in place while the follicle takes a rest. The hair doesn’t grow during this phase but remains intact in the follicle until it is shed.
-
Shedding: Losing up to 100 hairs a day is completely normal during this phase.
The telogen phase allows hair to rest and prepares it for the shedding process. It’s perfectly natural for old hair to stay in place as the new hair prepares to grow. If you’re noticing a bit more hair in your brush, it could be due to the natural shedding process occurring in this phase.
4. Exogen Phase (Shedding)
-
Duration: 2–5 months (overlaps with telogen)
-
Activity: During this phase, the old hair sheds while new hair begins to grow in the same follicle. Exogen is part of the natural shedding process, and it’s when you may notice hair falling out more frequently.
Shedding during the exogen phase is completely normal. Your follicles are clearing out the old hair, and fresh, healthy strands will soon take their place.
Factors That Disrupt the Hair Growth Cycle
Although your hair growth cycle is efficient, various factors can throw it out of balance. When this happens, you may experience thinning or shedding. Let’s explore some of the common disruptors:
Hormonal Imbalances
Hormonal shifts due to menopause, pregnancy, or thyroid issues can affect the hair growth cycle. The American Academy of Dermatology notes that hormonal changes are often a key contributor to hair loss in women. Conditions like polycystic ovary syndrome (PCOS) and thyroid imbalances can push more hair follicles into the shedding phase, leading to temporary hair loss.
Genetics
Genetics play a significant role in how your hair grows and sheds. If thinning or balding runs in your family, there’s a high chance that your follicles are more sensitive to hormones like DHT, which can shorten the anagen phase and lead to thinning. Studies show that 50 million men and 30 million women in the U.S. experience genetic hair loss.
Nutritional Deficiencies
Nutritional deficiencies can also play a role in hair loss. Key nutrients like iron, protein, and vitamins B12 and D are necessary for healthy hair growth. A study found that iron deficiency is a common cause of hair loss, especially in women. Without these nutrients, your follicles may struggle to produce healthy hair, leading to increased shedding.
Stress
Both physical and emotional stress can lead to telogen effluvium, a condition where an increased number of hairs enter the shedding phase. Stress can also shorten the anagen phase, making hair thinner and weaker. Research shows that high levels of stress can negatively affect the hair growth cycle, making it harder to maintain strong, thick hair.
Medications
Certain medications can disrupt the hair growth cycle and cause hair shedding. Medications like chemotherapy drugs or blood thinners are well-known for their ability to induce hair loss. If you’re taking medications and noticing increased shedding, it’s important to consult with your healthcare provider.
Scalp Inflammation
Conditions like psoriasis or dermatitis can inflame the scalp and damage hair follicles. When your scalp is inflamed, it can’t maintain a healthy hair growth cycle, and your follicles may not be able to produce hair effectively.
How to Support Healthy Hair Growth
If your hair is showing signs of thinning or shedding, it’s important to take steps to restore and protect your hair health. Here are some key ways to support your hair growth cycle:
Personalized Consultations
Every person’s hair is unique, and understanding the specific cause of your hair loss can help you find the right treatment. BosleyMD offers personalized consultations to help identify what’s causing your hair loss and recommend tailored treatments. A specialist can give you the proper diagnosis and guide you toward the best course of action.
FDA-Approved Treatments
Minoxidil, finasteride, and laser therapies are FDA-approved treatments that can help stimulate hair follicles and promote hair regrowth. These treatments are scientifically proven to extend the growth phase and reduce shedding.
Surgical Solutions
In cases where hair follicles have completely stopped producing hair, hair transplantation may be the best solution. Hair transplants involve relocating healthy follicles to thinning areas of the scalp.
Nutritional Guidance
Sometimes, your hair’s health starts with what’s inside your body. A lack of essential vitamins or minerals can affect hair growth. Supplements containing biotin, zinc, iron, and vitamins D and B12 can help nourish your follicles and promote healthier hair.
Scalp Health
Healthy hair starts with a healthy scalp. If your scalp isn’t in good condition, your hair follicles can’t function properly. Using treatments that reduce inflammation, clear buildup, and nourish the scalp can help reset your follicles and create the best environment for healthier hair growth. Regular scalp care helps improve blood circulation, remove product buildup, and balance oil production, which all contribute to stronger, fuller hair.
Final Word
Understanding the stages of hair growth is essential for recognizing when something’s wrong with your hair. Most hair loss is temporary and can be reversed when caught early. By choosing gentle treatments, nourishing your hair from within, and following a healthy scalp regimen, you can help your hair thrive.
If you’re noticing excessive shedding or struggling with regrowth, BosleyMD offers trusted, science-backed solutions. From personalized consultations to clinically proven products, there’s a full support system waiting for you.
Try BosleyMD products today and start taking charge of your hair’s future.
