Hair Loss vs. Hair Shedding

Hi everybody, welcome to the first podcast of The Hair Loss Show. I’m Dr. Russell Knudsen.

And I’m Dr. Vikram Jayaprakash. Both Dr. Jayaprakash and I specialize in the medical and surgical treatment of hair loss in Australia and New Zealand. I’ve been doing it for 35 years, and Vikram.

I’ve been doing it for 8 years. I trained under you, and we both practice hair treatment.

Now, interestingly, if you type “hair loss” into the Google search engine, you’ll get over 360,000 hits immediately. That tells you just how popular the topic of hair loss is. Unfortunately, because there are so many hits for hair loss, it becomes a very confusing path for people to find useful information.

When I started managing hair loss in 1982, there were no medical treatments that worked for the common causes of hair loss, which were male pattern balding in men and female pattern hair loss in women. There was nothing. In that vacuum, where doctors couldn’t treat, swooped in a number of businesses with products making all sorts of claims about how they could influence hair loss and regrow hair. Some claims were quite outlandish, others more modest. But if you look today on the internet, you’ll find literally thousands of offers for different treatments making all sorts of claims. A tip for the general public: If there are a thousand treatments out there, most of them don’t work.

So, what we seek to do for you today and in the next series of podcasts is to try and demystify things. We want to give you some basic information about hair and hair loss to help you navigate this difficult task of finding credible information and advice.

The bottom line that we want you to take away from this is that hair loss is often a medical situation or a medical problem. Therefore, a good starting point is to go to a doctor with experience in treating hair loss in both men and women. That is the clearest advice we can give to simplify your search for a way forward.

I think that’s a very good point. There’s a lot of information out there, and you and I experience that on a day-to-day basis when we consult with people. A lot of people have said, “Oh, I’ve done all this research.” And in that conversation, it comes out that there are fundamental errors in the information they’ve found. The information we’ll talk about in this series is all out there, but what I’ve found—and I’m sure you’ve experienced the same—is that there’s no real one place where people can get clear, concise, reliable information that isn’t tainted by someone trying to sell a product or service.

So, as Dr. said, we’re not offering you a product or recommending you buy anything. We want to give you information so you can educate yourself and make decisions based on a certain level of core knowledge.

To kick off, in today’s episode, we thought we’d explain what hair loss is and what hair biology really means.

When patients come to talk to us about hair loss, they often mention hairs they find in their comb, on the shower floor, or on their pillow. That’s actually hair shedding. Most people don’t understand the significance or normalcy of hair shedding, so let’s start with that, and then Dr. Vikram will talk you through the growth cycle of hair follicles.

Hair shedding means that the hair has finished growing, it detaches from the skin, and it falls out. What’s important to understand is that every hair on your head goes through this process at some point. The cycle length, which the doctor will talk about, determines the shedding rate. There are also other factors that can influence it, such as different seasons, travel overseas, fevers, childbirth, drug therapies, or even acute stress. All of these can change shedding rates.

But shedding is not the same as hair loss. Just as a teaser, the first thing to understand is that the normal range of daily shedding for most people is between 50 to 100 hairs. This may seem hard to believe, but mathematically, that is true.

Yes, it’s an interesting concept. A lot of people come in and say, “Oh, look, I go to bed and wake up and find all these hairs on my pillow.” And the key is to distinguish between hair shedding and hair loss. We all have hairs on our head, and they all go through a cycle. They grow to a certain length, which is predetermined by a variety of factors. Genetics is one, and that’s something we can’t control. If we just let our hair grow, it will grow to a certain length, and at some point, it will come to the end of its cycle and fall out. Then, there’s a slight latent period before the next hair starts growing.

Thankfully, not all the hairs on our body or scalp follow that exact same cycle. This is why we don’t lose all our hair at once. Different hairs fall out at different times, so not all hairs shed at once. It’s a gradual process that happens over time, at different rates, and at different times of the day, week, month, and year. So, when a hair grows, falls out, and is replaced by another hair, that’s not hair loss—that’s normal hair shedding.

So, what’s the range for the growth phase? What’s the normal rate of hair growth for scalp hair?

Normally, we see that hair grows about a centimeter per month for most people on average. There are certain variations, of course. The hair cycle for most people falls between three to five years.

Right, so if you have a long five-year cycle, your hair will grow at a centimeter per month, meaning your hair could grow to about 60 centimeters before it falls out. But if you have a three-year cycle, your hair will only grow to around 36 centimeters. This is the difference between someone with a long cycle and someone with a shorter one. We often hear patients tell us that when they were younger, they could grow their hair to their waist, but now it only grows to their chest. The difference is age and the cycle length. You may have the same hair length, but as you age, your hair may not grow as long.

It’s a good point, absolutely. And sometimes the hair length itself can make things seem even worse. For example, when a woman loses five hairs, it can look a lot more obvious in the bottom of the shower than if I lose five hairs, with my longer hair. It’s also about the appearance, and sometimes that adds to the anxiety.

Right, so as I said earlier, 50 to 100 hairs per day. If you’re someone with a five-year cycle, you might shed about 50 hairs a day. If you have a three-year cycle, it might be closer to 100. But when does the hair actually fall out? Well, it detaches from the skin and stays there until something tugs it out—typically when you wash or brush your hair. This is what we often hear: “Doc, every time I wash my hair, it falls out!” So, what happens is, they stop washing it so often, but even more falls out.

This is an easy trap to fall into. If you wash your hair once a week, you’re mostly going to lose a week’s worth of hair. If you wash it every day, you’ll only lose a day’s worth of hair. This is something that’s easy to confuse, but at the end of the week, it’s still the same number of hairs shed.

So, that’s hair shedding. Now, what’s the difference between hair shedding and hair loss?
In a normal cycle, when the hair has finished growing after 3, 4, or 5 years, an identical, healthy hair will replace it three months later. Hair loss, however, occurs when the strength of the shaft is lost, which means a thinner hair that may not be able to replace the lost hair.
The number of hairs on the scalp varies between 95,000 and 105,000 hairs. Normally, 90% of these hairs are growing, and 10% are in a resting or shedding phase. But with hair loss, you lose either the number of hairs or the quality of the hair shaft—meaning thinner or weaker hair.

That’s a really important point. Sometimes people come in and say, “I’ve been losing hair really quickly.” The reality is, people don’t go bald overnight. Hair loss doesn’t happen like that. Most causes of hair loss involve a gradual thinning process where the new hair that replaces the fallen one is thinner. Over time, this cycle continues, and eventually, the hair gets too thin and frail to regrow.

Let’s talk about how age affects hair loss. Sadly, we all lose hair over our lifetime, but it’s different for men and women. Let’s put up the first diagram.

We’ll have age on the x-axis and the number of hairs on the y-axis. For both men and women, between the ages of 20 and 25, hair numbers stay relatively stable. But from your mid-20s, both men and women begin to lose hair gradually as part of the aging process. The interesting thing is, for women between the ages of 20 and 40, the shaft diameter of their hair actually increases slightly, thanks to estrogen. Even though they lose some hairs, the remaining ones become thicker. However, after the early 40s, as estrogen levels decline, so does the thickness of the hair.

For men, there’s no increase in shaft diameter because there’s no estrogen to stimulate it. For men, both the number and thickness of the hairs decline gradually from the age of 25. This is normal aging.

Right, and this is important because when we’re looking at male or female pattern hair loss, we know that the earlier it starts, the more noticeable the hair loss can become over time.
Exactly. And this is why, when people come in and say, “I don’t have a family history of baldness,” we can look at their hair history and say, “You may be experiencing early male or female pattern hair loss.” It often starts out subtly, but with time, it can become more noticeable.

It’s a great point. Now, before we wrap up, let’s briefly touch on how hair loss can impact your health emotionally.

It’s a really important point, and something we’ll discuss in later episodes. People who are experiencing significant hair loss often feel self-conscious. It can affect confidence and mental health, which makes it even more critical to seek good advice and treatment.
Alright, so that’s our first episode on understanding hair loss.

We hope we’ve made the topic a little clearer and helped you understand the basics. In future episodes, we’ll dive into more specific types of hair loss and discuss treatments in depth.

Until next time, thanks for listening to The Hair Loss Show.