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Hair Loss Myths with Dr Wendy S Levinbook

08/25/22 Wendy S. Levinbook, MD, Hartford Dermatology Associates;

Season 4 | Episode 5


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Title: Hair Loss
Merck Manuals Medical Author: Wendy S. Levinbook, MD, Dermatologist at Hartford Dermatology Associates in West Hartford, Connecticut

Opening Audio: Going bald is not something you should try to fight, because it's a fight that you can’t win.

Joe McIntyre: Hello, and welcome back to the Merck Manuals Medical Myths podcast, where we set the record straight on today's most talked about medical topics and questions. I'm your host Joe McIntyre. And on this episode, we welcome Dr. Wendy Levinbook. Dr. Levinbook is a dermatologist at Hartford Dermatology Associates in West Hartford, Connecticut. Today, we're here with her to talk about hair loss, Dr. Levinbook. Welcome to the podcast.

Wendy S. Levinbook, MD: Thank you for having me.

Joe McIntyre: Now there are a ton of myths, questions, and misunderstandings when it comes to hair loss. Many of us are curious about what causes hair loss, how hair loss is treated, and if hair loss can be prevented, but first let's start off with a question that I'm sure many of us want to know the answer to. Why do some people experience hair loss?

Wendy S. Levinbook, MD: Well, hair loss can occur for many different reasons. The most common cause of aging or genetics, which is also known as male or female pattern, hair loss or androgenic alopecia. But there are lots of other causes as well, such as underlying systemic disorders, hormone imbalance, other endocrine disorders, lupus or nutritional deficiencies, autoimmune disorders, such as alopecia areata, drugs, such as anabolic steroids or medications such as chemotherapy medicines, infection, trauma to the scalp, such as compulsive hair pulling, wearing tight ponytail or braid or burns, physical stress, which is very high fever or pregnancy or severe psychological stress. So, there are really lots of different causes.

Joe McIntyre: Yeah, there's obviously been a lot of talk in the media recently about alopecia because of Jada Pinkett Smith and her husband Will Smith and the incident at the Oscars. Can you tell our listeners what exactly alopecia is? And is it different from regular old hair loss or baldness?

Wendy S. Levinbook, MD: Yes, the term alopecia is definitely being used a lot in the media right now. And alopecia is just a medical term for hair loss. The two are synonymous. Alopecia is a nonspecific term that includes many different types of hair loss, due to many different causes in different pattern than on any part of the body. Baldness however, is a more specific term that describes diffuse hair loss on the scalp.

Joe McIntyre: Now is the hair that falls out daily in the shower or when brushing your hair a sign that someone's going to have more hair loss or is that just kind of a natural experience of living your life?

Wendy S. Levinbook, MD: No, that isn't natural experience of living your life. So, the hair that falls out daily in the shower, or when brushing your hair is completely normal. A typical scalp has about 100,000 to 150,000 hairs. And so, it's normal for 50 to 100 of those to fall out daily as they complete their growth cycle. And basically, hairs grow in three phases. There's a long growing phase called the antigen phase. And this typically lasts anywhere from two to six years. And as an aside, the maximum length that your hair can grow is a function of the length of your antigen growth phase. And this is genetically determined. So, you know think of Crystal Gayle who had that floor length hair at one point in her career. She must have had an extraordinarily long energy hair growth phase because most people do not grow their hair that long. But in any case, after the growth phase, there's a transitional phase of candidate which lasts a few weeks. And then finally there's a short several month-long resting phase that each hair goes through called the telogen phase. And 50 to 100 hairs will reach the end of this phase and fall out each day. And then the growth cycle for those hairs begins again. So, when you see a small amount of hair falling out in your brush or in the shower again don't worry, this is normal.

Joe McIntyre: When you mentioned that hair has a maximum growth length, I'm assuming that's why hair on someone's arm or someone's leg or wherever else in your body that's not your head kind of stops at some point. Is that correct?

Wendy S. Levinbook, MD: Yes, there is a finite growth phase for hairs and that growth phase differs in different spots on your body.

Joe McIntyre: Do men experience hair loss more frequently than women? It seems like they do but is that just a myth? What's the actual truth there?

Wendy S. Levinbook, MD: Hair loss is more common in men and the reason is that the most common type of hair loss is hair loss associated with aging and there are lots of different statistics for this. But it's thought that this affects over 70% of men and 50% of women over the age of 80. Men do suffer more hair loss on average than women.

Joe McIntyre: Why do some people start to experience hair loss earlier in life compared to others and some later and then some not at all? What's the deal there?

Wendy S. Levinbook, MD:  Yeah, that's a good question. And the answer is just genetics and different sensitivities to circulating hormones. Some people are just programmed to lose their hair early, some later and others will never lose their hair. So, if we can figure out why this is we would probably have some great therapies or hair loss and they are working on it, so we’ll get to the bottom of that.

Joe McIntyre: Is it true that hair loss in men is passed down from the mother side of the family while hair loss and women is passed down for the father side? Is that the truth?

Wendy S. Levinbook, MD: No, this is such a common belief and I'm asked it all the time but it's not true. Male and female pattern hair loss is genetic, but it can be passed down by either one of your parents regardless of whether you are male or female, so not true.

Joe McIntyre: Now how about this one, can wearing hats cause your hair to fall out?


Wendy S. Levinbook, MD: No, also not true wearing a hat will not cause hair loss. It's not true that the scalp needs to breathe. And in fact, hats are a great way to protect the scalp from the sun, so I do recommend their use.

Joe McIntyre: Now I'm sure a lot of people have heard about the importance of shampooing or not shampooing daily. Does too frequent shampooing contribute to hair loss and how about sleeping with wet hair? What is the deal when it comes to shampooing and sleeping in wet hair?

Wendy S. Levinbook, MD: Yeah, so washing your hair every day will not contribute to hair loss. So that's a myth, as far as sleeping with wet hair is a little more debatable. The hair shaft is weaker when it's wet. So, there might be an increased risk for hair breakage when you're sort of tossing and turning on your pillow while you're sleeping. So, I would say that it is probably better to dry your hair before going to sleep. If you can.

Joe McIntyre: Now, when people suffer from hair loss, does that mean it's permanent? Or is there a way to grow back? What are some of the avenues that people use to grow their hair back if that actually is the case?

Wendy S. Levinbook, MD: Yeah, not all hair loss is permanent. Male and female pattern hair loss typically is permanent. Although there are other types of hair loss. You know that caused by trauma, some types of hormonal changes, pregnancy, eating disorders. Other systemic illnesses that can be temporary. So not all as permanent, but there are things you can do to slow down hair loss or prevent further hair loss. For hair loss associated with aging there are two FDA approved medications. Rogaine is approved for use in men and women and Propecia is approved for use in men only. And then there are hormonal therapies that can be used if a hormonal imbalance is the cause, and then avoiding traumatic haircare practices such as excessive styling coloring, straightening or hot comb use can also be helpful to prevent or slow down further hair loss.

Joe McIntyre: I'm sure we've all also seen ads on TV or online about hair growth or hair replacement. Is that real hair? What's the science behind that?

Wendy S. Levinbook, MD: Well, you know, it depends on the ad. They're advertising but you know there are medications that can induce hair growth or thicken existing hairs such as Rogaine, Propecia, and some other hormonal modulators. There are also devices such as low-level laser light sources, and then there's a technique of injecting platelet rich plasma that are thought to grow real new hair. In terms of hair replacement, this usually refers to hair transplantation, where healthy hair follicles are taken from areas of dense hair growth on the scalp, and then implanted were needed to grow new real hairs. So yes, ultimately new hairs can be grown.

Joe McIntyre: How about vitamins like biotin, I'm sure a lot of people either take these supplements or heard of them. Do they help with hair growth?

Wendy S. Levinbook, MD: Yeah, a large percentage of my hair loss patients report taking biotin but there really isn't much scientific evidence to support their use. Unless one has a true biotin, deficiency which is really very rare. Biotin has not proven to be helpful for hair loss and in fact, taking biotin can interfere with certain lab tests results leading to inappropriate treatment and misdiagnosis of certain conditions. So, you do have to be careful when you take this supplement. I just typically recommend that patients eat a healthy diet and avoid nutrient deficiencies to help keep their hair healthy rather than take biotin or other supplements.

Joe McIntyre: Doctor Levinbook, do some haircare routines contribute more to hair loss than others? Are there things or routines that people should avoid when it comes to treating their hair?

Wendy S. Levinbook, MD: Yes, so there are some haircare practices that are more traumatic to the scalp and the hair shaft and that can lead to hair loss, such as traction alopecia which is caused by braiding the hair too tightly or wearing ponytails you know too tightly, you know over and over again. And then there are certain practices such as excessive styling, hot comb use, things like that, that can cause damage to the hair and the scalp.

Joe McIntyre: Now, here's a myth that we've seen I'm sure in popular culture and I'm sure a lot of people have seen online when someone shaves either their face their chest, their arms or legs, any other part of their body. Does that hair that comes back in is that thicker than it would be if they hadn't shaved that part of their body?

Wendy S. Levinbook, MD: It is not, everyone does, you know believe that. And it seems that way because when it comes in at first you know it's a very short hair and does seem to be thicker than regular hair, but it is not. As it grows out, you would notice that it is the same thickness as all the other hairs on your body, so that is not true.

Joe McIntyre: So Dr. Levinbook as we're closing out here, Where should our listeners go if they're looking for resources or more information about hair loss, hair regrowth or hair health

Wendy S. Levinbook, MD: So, the American Academy of Dermatology has a very good website with lots of good information on there. And then of course, the Merck Manual, also has lots of good information.

Joe McIntyre: Well, Dr. Levinbook, thank you so much for joining us on this podcast. Certainly, a lot of interesting topics and a lot of great conversation about hair loss, hair growth and how our hair health is important to everybody. I'm sure many of us deal with hair loss in some form. So, it's great to get to hear from the experts.

As we close out. I'll let Dr. Levin both leave our listeners with the final thing as we always do.

Wendy S. Levinbook, MD: Medical Knowledge is Power Pass it On.