If you haven’t seen it yet, the Andrew Huberman hair loss & hair regrowth episode is–like most of his material–a thorough and expertly delivered resource. What’s particularly interesting is the relationship he draws between hair loss and circulation, which is highlighted by the circulation-boosting molecule known as minoxidil (the active compound in Rogaine®).
Although he occasionally gets things wrong (see this article on his scientifically disproven stance on Tongkat), Dr. Huberman’s information is on point ninety-nine times out of a hundred, and we love learning from his podcast.
Most people know that circulation is of course crucial for cardiovascular health, but considering that every part of your body requires a constant supply of nutrients and oxygen, circulatory health can affect nearly every aspect of your wellbeing.
Hair is no exception.
The relationship between hair growth and circulation is well-known. For example, smoking and vaping are risk factors for hair loss because nicotine is a vasoconstrictor (and smoking also generates free radicals that can damage hair follicles).
Minoxidil can be taken internally or used topically as a foam. It works on the principle of increasing circulation to the hair bulb, and seems to be effective for many, but–according to Huberman–does come with side effects for some.
[Disclaimer: none of this is medical advice, as we’re merely summarizing Dr. Huberman’s presentation on this topic. Discuss all prescription drugs with your doctor.]
Huberman on Basic Hair Physiology and the Importance of Healthy Circulation
Huberman does an excellent job of explaining the basics of how hair growth works on a cellular level. If you’d like to watch these sections, they’re called ‘Hair Anatomy & Stem Cells’ and ‘3 Phases of Hair Growth’.
You can also check out this page from his website, which has additional learning resources and a detailed list of time-stamped links that will take you to each section of the video.
Though this article focuses primarily on how circulation affects hair growth, Dr. Huberman also discusses the importance of hormones as well as a multitude of other treatments, such as microneedling, botox, and DHT blockers.
Here’s a quick summary of the most relevant parts on hair physiology:
- Stem cells are what give rise to all hairs and reside in the hair bulb (stem cells are essentially undifferentiated ‘raw material’ cells that can transform into any kind of cell)
- These stem cells transform into keratin-rich ‘daughter’ cells, which stack on top of each other to form hairs
- There are capillaries that go into the hair bulb and support the stem cells’ differentiation into hair cells
- The delivery of nutrients and oxygen from these capillaries to the hair bulb is essential for healthy hair, which is why boosting circulation is so helpful
- Common practices–like avoiding tight-fitting hats, doing scalp massage, and using heat therapies–are all a reflection of the importance of increasing blood flow to the hair bulb (there isn’t a ton of research to back these up, but it makes logical sense that they might be at least somewhat helpful)
- There are 3 phases of hair growth:
- Anagen Phase – the stem cells become the cells that make up hair proteins (usually 2-8 years for hairs on the head but only a few months for eyebrows, for example)
- Catagen Phase – hair follicle begins to detach from the bulb and pushes up higher toward the skin
- Telogen Phase – hair bulb starts to pinch off the follicle and then recedes and dies
How Minoxidil Works to Slow Hair Loss According to Dr. Huberman
Dr. Huberman says:
“One of the longest standing treatments for halting and reversing hair loss is so-called minoxidil. Minoxidil…was actually a drug that was developed to treat hypertension. So this is a cardiac drug that lowers blood pressure, and it does that by causing vasodilation. It allows more blood flow, not just to the hairs on your scalp…it does that by extending the anagen phase.”
So, in essence, the action of minoxidil is simple: get more blood flowing through the capillaries in your scalp to the hair bulb in order to nourish the stem cells there, helping them turn into healthy, keratin-rich hair cells. This extends the anagen phase, meaning that each hair will last longer before the hair bulb dies.
Dr. Huberman also notes that minoxidil is better at slowing down hair loss than reversing it, and does need to be taken indefinitely, so you’re committing to taking a tablet or applying the foam to your scalp for potentially decades.
Minoxidil Side Effects: Sexual, Circulatory, and More
Here’s a summary of Dr. Huberman’s comments on minoxidil dosing and side effects:
- Doctors will often start people at the lowest dose and work up in order to reduce side effects
- The topical solution does absorb into your general circulation, so you can still experience some of the same side effects that you would from the pill
- It can sometimes cause swelling of the ankles, headaches, low blood pressure, and dizziness
- It also increases prolactin, a hormone that’s released by your pituitary gland and (as the name suggests) is involved in the production of breast milk
- Because of its effect on prolactin, minoxidil can sometimes cause inappropriate lactation in women, increased growth of breast tissue in men (gynecomastia), and decreased libido
- Prolactin is a neurotransmitter-like hormone that is known to antagonize dopamine, and thus can negatively affect mood, focus, and motivation (note that dopamine and testosterone enhance each other, which has to do with one of the ways that Tongkat Ali can boost T levels)
He doesn’t mention exact percentages for how often these side effects occur, so it’s unclear how common these issues are. He does, however, stress that higher doses are much more likely to cause issues.
On the website Askapatient.com, which takes reviews of drugs from real patients, there are currently 309 ratings for minoxidil with an average rating of 1.6 stars (it’s possible that people are more likely to use these sites to report negatively, though).
It’s understandable why people would use this compound, despite the potential for side effects, because hair is such a big deal to many of us. In fact, Huberman says that–based on his studies–hair loss causes a large number of people significant psychological distress.
Healthy Living, Hair Loss, Stress, and Adrenal Function
Surprisingly, Dr. Huberman says that there’s actually agreement that stress can cause or worsen hair loss:
“It is true that our psychological well-being can impact both the coloration (or lack thereof) and the growth rates of our hair. That’s a real thing. And the reverse is also true, which is that, as hair starts to thin or fall out, or change color, many people experience intense anxiety or even depression. This was not something that I was really aware of.”
Huberman does his homework. He typically performs a thorough literature review and speaks with domain experts before he releases a podcast. Thus, it seems that this connection was something that he only discovered as a result of his preparation.
We of course have no opinion on which modalities you should use to treat or prevent hair loss, and whether you decide to use a medication is entirely up to you and your physician. However, considering that healthy eating, supplements, stress reduction, and exercise can have a dramatic impact on both your mental wellbeing and your circulatory health, it’s clear that hair health is deeply connected to lifestyle.
Humans have recognized the connection between the adrenals and hair for thousands of years.
In Traditional Chinese Medicine (TCM), for example, it’s understood that your hair is a reflection of your kidney health, which may seem odd at first, until you realize that:
- In TCM, ‘Kidney Qi’ also includes the function of the adrenal glands (which sit just above the kidneys)
- Your kidneys and adrenals regulate your blood pressure and thus profoundly affect your circulation
- Your adrenal glands secrete the stress hormones adrenaline and cortisol
The word ‘adrenal’ simply means ‘above the kidneys’ and it’s obvious that adrenaline is named after it. What’s lesser known, however, is that the ‘cort’ part of ‘cortisol’ is actually a reference to the adrenal cortex (the outer region of the gland), which also secretes sex hormones like testosterone and estrogen.
If you take a look at the different molecules your body makes that affect hair health, nearly all of them map perfectly onto the adrenal glands. In the video, Huberman also talks about how hormones like dihydrotestosterone (DHT) and insulin-like growth factor 1 (IGF-1) are involved in hair growth, and both of these come from the adrenal glands (IGF-1 directly and DHT indirectly).
So, if you want to keep more of your hair, then the kidney-adrenal system may be the best place to start, and stress management is critical in this department. Additionally, many of the more holistic-leaning cardiologists out there understand that your diet can substantially impact how well your blood flows, so consider doing what you can to eat clean.
And though stress is rarely the sole cause of hair loss–which is often complex and multifactorial–it’s certainly a major player. Whether it’s herbs, diet, getting better sleep, or stress-reduction practices like breathwork or meditation, mitigating stress hormones is always a good idea.
If you’d like to check out some blogs on hormone health, Dr. Huberman, and how you can reclaim your vitality naturally, you might enjoy these:
