Have you ever wondered how much hair loss is normal? Plenty of people aspire to have the voluminous, healthy hair they see on shampoo commercials. It can feel stressful to see strands of hair wash down the shower drain. But did you know some shedding is normal? Read on to learn how to tell the difference between excessive hair shedding and routine hair loss.

Routine Hair Shedding: Why It Happens And How Much to Expect

Routine hair shedding is a natural part of life. It’s normal for a person to shed between 50 and 100 loose hairs per day. When all of those hairs are concentrated in one place, like your shower drain, it can look like a lot, especially if you have long hair strands. But remember, some amounts of hair shedding is normal.¹

To put it into perspective: the average person has about 100,000 hair follicles and a similar number of hairs on their head. The loss of 50-100 hairs represents just a small percentage of the overall hair on your head. It’s not likely that this amount of shedding will affect the appearance of your hair.²

Hair Shedding Vs Hair Loss: What’s The Difference?

Excessive Hair Shedding

While routine hair shedding is normal, sometimes the body sheds an excessive amount of hair. This is typically brought on by a stressful event.

Excessive shedding, known as telogen effluvium, peaks a few months after the stressor occurs. As your body readjusts, the shedding stops, and your hair grows back. In fact, that’s the main difference between hair shedding and hair loss. Hair shedding is temporary hair loss. The hair will grow back and regain its normal fullness. Hair loss, however, is thought to be more permanent.³

Hair Loss

Hair loss, or anagen effluvium, happens when something stops the hair from growing. Here are a few common causes of hair loss:

• Genetics
• A reaction of the immune system
• Certain medications and treatments
• Hairstyles that pull the hair
• Damaging hair care products⁴

With hair loss, the hair won’t grow back until the cause of the issue stops. In some cases, it may not grow back. If you’re experiencing excessive hair loss or shedding, the best thing to do is consult your doctor.

How Your Hair Grows

Understanding hair growth cycles can shed some light on the process of hair loss and shedding.

The hair follicle cycles through four different growth phases: the anagen phase, catagen phase, telogen phase, and exogen phase. The different hairs on your head are at different stages of their lifespan at any given time.⁵ Here’s what happens in each phase:

Anagen Phase

The anagen phase is the growth phase of your hair’s life cycle. This is the phase where the strand is actively growing. It can last 2 to 6 years. About 90% of your hair strands are currently in this phase. When something stops your hair from growing in this phase, it’s called anagen effluvium, or hair loss.^6,7

Catagen Phase

Next comes the catagen phase, which is also known as the regression phase. This is a short transition phase that lasts only a few weeks. About 1 to 2 percent of your hairs are in this phase at any given time. During this growth phase, the hair stops growing and gets ready for the next phase.⁸

Telogen Phase

The telogen phase is also known as the resting phase. Hairs in this phase are called “club hairs.” They are no longer growing. They are resting until a new anagen hair grows in the follicle and pushes them out.

If something disrupts your hair growth cycle, it may cause more hairs to enter this phase. When this happens, this will cause a greater number of hairs to shed when they enter the exogen phase a few months down the road.⁹

Exogen Phase

In this last phase, hair is shed from the scalp. This is where the normal shedding of 50-100 hairs occurs. This is also where excessive shedding may occur if there were a larger-than-normal amount of hairs in the telogen phase. As the old hairs fall away, new hairs start to grow in the follicles, and the process starts over.^10,11

Possible Reasons For Excessive Hair Loss And Shedding

Some daily hair loss is normal. But if you sense that you may be losing more hair per day than the average person, you’ll want to identify the hair loss trigger. There are a few known factors that may cause abnormal hair loss.

If you are at all concerned about hair loss, consult with your doctor right away. They can give you the best information on this topic.

Extreme Stress

A single stressful event can cause a condition called telogen effluvium. With this condition, the anagen phase of hair growth slows down and the telogen phase happens earlier than normal. This may cause large amounts of hair to temporarily fall out, but it will typically grow back.¹²

Thyroid Conditions

A medical condition related to your thyroid may interfere with the development of new hair at the root. Your other hairs will fall out according to their life cycle, but they may not be replaced with new growth. This could result in thinning hair and hair loss.¹³

PCOS

Polycystic Ovary Syndrome (PCOS) could also be a source of hair loss. This is typically due to high levels of androgens (like testosterone) in the body of individuals with PCOS. Androgen hormones may be related to hair loss.¹⁴

Alopecia Areata

A condition called alopecia areata can cause clumps of hair to fall off the scalp. If you believe you are experiencing abnormal hair loss like this, call your doctor.¹⁵

Ringworm

Ringworm is a fungal infection (not actually a worm) that can affect your scalp. If you have ringworm on the scalp, it may cause small patches of itchy, scaly skin. Your hair may break off in these areas.¹⁶

Childbirth

After childbirth, new moms may shed more strands of hair than usual. Dermatologists call this condition “excessive shedding.” It is normal and should be nothing to worry about. If you’re concerned, consult your doctor.¹⁷

Birth Control

Some types of birth control medication may cause hair to thin or fall out. This happens because the pill can cause hair to jump from the anagen growth phase to the telogen resting phase more quickly than usual. It might also cause hair to stay in the telogen phase for longer than usual. The result is a form of hair loss called telogen effluvium.¹⁸

Sudden Weight Loss

Sudden and rapid weight loss can act as a hair loss trigger. If the weight was lost due to a crash diet, a nutrient deficiency may be at play. Nutritional deficiency can impact the structure and growth of hair, causing telogen effluvium.¹⁹

Tight Hairstyles

Hairstyles that pull on the scalp – like a sleek ponytail, cornrows, or tight braids – may lead to permanent hair loss. These styles can damage the hair follicle, making it difficult for hair to grow back. The medical term for this is traction alopecia.²⁰

Hereditary Hair Loss

Hereditary hair loss is the most common cause of hair loss. This is a natural condition caused by a combination of genetics, hormones, and aging. This condition is also called androgenetic alopecia.²¹

When Should You Worry About Hair Loss?

If you’re noticing a few extra stray strands of hair in your hairbrush, you likely have nothing to worry about. Remember, some routine hair shedding is completely normal.

But if you’re concerned about your hair health or excessive shedding, call your doctor. As you can see, there are many explanations for excessive shedding. Your doctor will be able to provide you with personalized advice that is targeted to your situation.