Hi everybody. It’s Dr. Eric Balcavage, we’re back for another edition of Thyroid Thursday. Today I talk about hair loss or hair thinning and thyroid physiology. There’s definitely a connection between hair loss or hair thinning and thyroid hormone reaching your hair cells, your hair follicles. All right. There’s a couple of key points we want to talk about. First is the difference between glandular thyroid problems and cellular thyroid problems. So glandular thyroid problems are where your gland is making too much or too little thyroid hormone. If it’s too much thyroid hormone, we call that hyperthyroidism. If it’s too little thyroid hormone, we call that hypothyroidism.
The primary cause of both glandular hyperthyroidism and hypothyroidism is typically an autoimmune condition, either graves’ or Hashimoto’s, and we’ve talked about those things in the past. Then we also have this process called cellular thyroid dysfunction, where you have cellular hyperthyroidism, which is too much thyroid hormone reaching the cells and cellular hypothyroidism where there’s too little T3 getting to the nuclear receptors in the cells. Okay? Both cellular, hyper and cellular hypothyroidism can drive hair thinning and hair loss.
Now, what’s important to understand is that if you have glandular hyperthyroidism or glandular hypothyroidism, you’re going to have cellular hyperthyroidism or hypothyroidism, but you can have cellular hyperthyroidism or cellular hypothyroidism without any problems of the gland because when you have cell stress, typically what happens is instead of the T4 being converted to T3 and the T3 getting to the nuclear receptor, that T4 comes into the cell and it gets converted to reverse T3 which decreases the amount of T3 reaching that nuclear receptor, and that’s going to cause cellular hypothyroidism and that’s going to have a significant impact at that cellular level. Typically, we don’t see cellular hyperthyroidism as much being a problem without the glandular output, but it can definitely happen. Second key point I want to make is TSH and T4 are not reflective of what’s happening in all your cells at the same time.
I know in the allopathic model, that’s the primary mechanism to evaluate thyroid physiology, but really what they’re looking at is, is the gland producing too much or too little? Is the gland dysfunctional? And really what we need to get to is what’s happening at the cellular level, and the best way to really interpret what’s happening at that cellular level is to look at things like reverse T3 to see if you’re causing an increased deactivation of thyroid hormone. You can look at the T3 to reverse T3 ratios. If that’s less than 10 we typically see cellular hypothyroidism, and if we see a free T3 to reverse T3 ratio less than 0.2 then we have the cellular hypothyroidism going on. Okay? And last piece that I want to make sure I reiterate is thinning hair. It can be caused by too much or too little thyroid hormone getting to those hair follicles. Either one of those can cause thinning or hair loss.
So let’s talk about the hair follicle. Here’s your hair follicle. It grows from something called a Dermal Papilla. There’s something called the sebaceous gland there, and what happens is that the hair follicle goes through three phases. The first phase is called the Anagen phase. That’s the growth phase and thyroid hormone plays a key role in that growth phase. That growth phase can last two to seven years, and once that hair follicle reaches that phase of growth where the growth has stopped, we enter into what’s called the Catagen phase, and the hair follicle separates from this Dermal Papilla and essentially it’s the beginning of the death of that hair follicle. That usually lasts about 10 days, and then we’re in this transition phase that’s called the Telogen phase that lasts about three months from the time that this one separates and a new hair follicle takes its place.
At any one period of time, you have about 150,000 hair follicles. Usually in a healthy state about 85% of those hair follicles are in the growth phase, and about 15% are in the regrow phase or that telogen phase. Okay. You shed about 100 hair follicles per day if you have normal physiology, so some hair loss on a regular basis is not unusual, but if it does become excessive, then you typically have either too much thyroid hormone reaching that cell or too little. The most common thing we see is too little thyroid hormone reaching the cell.
And what’s going to impact thyroid hormone reaching that cell or what we would say the deactivation of thyroid hormone at the cellular level is typically some form of cellular stress and that cellular stress could be caused by a decreased blood supply. It could be a stress response, anxiousness, anxiety, or some type of trauma. It could be some type of medication that’s impacting either the thyroid physiology or decreasing blood flow. It could be birth control and could be hormone imbalances. It could be things in your diet that are creating the deactivation of thyroid hormone inside your cells. It could be what you’re doing to your hair with hair treatments that are toxic to the cells and causing deactivation of thyroid hormone. Those chemicals or treatments that damage the hair follicle too soon or too quickly. It could be nutritional deficiencies. It could be toxicity, but at the root of most cases of what we call cellular hypothyroidism is some of stress or inflammatory process.
If you have a thyroid physiology that’s impacting your hair growth, we typically see a generalized thinning through the whole head of hair. If it’s some other form, it might seem more patchy hair loss. Okay. The good news is that if it’s a thyroid related problem, it’s typically a temporary issue. If we can restore normal thyroid physiology to the hair follicles, then we can get the return of a normal head of hair.
So if you have glandular hyperthyroidism, like we’re pumping out too much thyroid hormone that’s causing cellular hyperthyroidism, then reducing that thyroid hormone production is the key way and in the medical model, then you may use medications to slow down that production or block the production of thyroid hormone and in the functional medicine model, there’s a number of things we can do to slow the thyroid hormone physiology down as well.
If you have hypothyroidism at the cellular level, then we have to dig in and figure out what’s causing that cell stress. If it’s a glandular hypothyroid condition and you put in T4 into the system and you normalize TSH and T4, your hair might grow back if there isn’t any cellular stress preventing that conversion of T4 to T3. But if there’s cellular stress going on via one of these mechanisms, and TSH is normalized and T4 is normalized, essentially what you’ve done is you’ve normalized the thyroid levels in the blood and at the brain, but in your peripheral tissues, the cell stress is continuing. You’re still getting the deactivation of thyroid hormone once it reaches the hair follicle, and you’re still going to have thinning hair. So if it’s glandular and you’ve been diagnosed with primary hypothyroidism, you get the LT4 treatment, Synthroid levothyroxine, TSH normalizes, T4 normalizes, but your hair is still thinning. It’s still breaking off, you’re still having excessive hair loss, then you have that cellular hypothyroid condition and that’s where we need to dig in and figure out what’s causing your cellular stress.
Is it some type of toxicity? Do you have some type of infection? Do you have Hypoxia? We have to figure out what’s causing the hair follicles to favor deactivation of T4 and T3 versus the conversion of T4 to T3 and that T3 reaching that nuclear receptor. Unfortunately in the allopathic model, there’s probably not going to be a lot of time spent on trying to figure that process out, but that’s where functional medicine shines and trying to get to that root cause issue.
So if you have thinning hair or hair loss and you think you have a thyroid condition or you’ve been diagnosed with a thyroid condition, TSH is normalized, T4 is normalized, but it’s still thinning, still have hair loss, you have to look at, do we have a cellular hypothyroidism condition going on? And if we do, we need to identify why. And if you don’t have a cellular thyroid physiology issue going on, then we have to look for what are the other mechanisms that may be causing your hair loss.
So, to wrap this one up, thyroid hormone plays a key role in every aspect of hair physiology, the growth phase, the death phase, keratin levels, the texture, and the pigmentation. So if you have problems in any phase of your hair cycle, thyroid hormone probably plays a role and we need to get to the root cause issues, and that’s really where functional medicine shines, finding the root cause issue. I wish there was something we could just tell you if you take Biotin, if you take selenium, that will fix it. But ultimately, if there’s some type of cell stress, you have to get to that root cause issue. All right? hopefully this helps. If you have questions about your thyroid health, schedule a free 15-minute health evaluation, here!