Miracle hair growth spice or well-intentioned rumor?
The spice I’m talking about is cayenne pepper.
Many bloggers tout the miracle hair-growing properties of cayenne pepper.
While these results may be promising, are they truly based on science? Or is it just a simple coincidence?
In this article, I’ll pick apart the actual science on cayenne pepper for hair loss and answer the question:
Does cayenne pepper really work for hair growth?
Make sure you read until the end for the ways to use cayenne pepper for hair.
Quickly, make sure you take the free hair quiz later in this article.
What Is Cayenne Pepper?
Cayenne pepper is a red chili. It’s often used in powder form and added to food and beverages.
Current research suggests that cayenne pepper may boost your metabolism (1). However, this is still under investigation.
For this reason, it’s often a popular additive in weight loss and cleansing drinks.
But, it might go beyond potential weight management.
The stimulating, thermal effect of cayenne pepper has drawn people to use it on their scalp to promote hair growth.
This effect is mediated by a compound called capsaicin. It’s what gives cayenne pepper its spice and thermal properties.
Although cayenne pepper also contains other beneficial compounds, this is by far the most relevant to hair growth.
But, just because it sounds beneficial, doesn’t mean it always is.
So, let’s take a deep dive into understanding how capsaicin works in the body and how that might relate to hair growth.
Key Takeaway: Cayenne pepper’s heating and stimulating properties are attributed to capsaicin, the compound that gives cayenne pepper its spice.
How Does Cayenne Pepper Work?
Here’s the cool thing about capsaicin:
It acts on a bunch of receptors to exert various effects.
I’ll discuss each one in detail and explain to you how it relates to hair growth.
Capsaicin and TRPV1
You know that feeling you get on your tongue when you eat spicy foods? The stinging pain?
What you’re feeling is actually the activation of transient receptor potential vanilloid 1 (TRPV1) receptors on the tongue. These receptors are also found in various other cells in the body.
These receptors are involved in the perception of pain. However, they also have other functions.
Capsaicin is one of the most potent activators of TRPV1 receptors.
When it binds to these receptors, it causes a huge increase of calcium within cells. This modulates the cell function in many different ways. These changes can be dependent on the type of cell.
What does this mean for hair?
Interestingly, research using animal models and cell cultures suggest that it may not be so good.
In animal studies, TRPV1 activation leads to hair follicle regression from anagen (growing phase) to catagen (resting phase) (2).
Mirroring these results is a study on cell culture of human hair follicles (3).
When TRPV1 was activated, hair growth was stunted, hair follicle cell division was suppressed, and more hair follicle cells died off.
These results are enough to make you question whether or not cayenne pepper is truly effective.
But, there’s more to the story.
TRPV1 activation isn’t simply about the activation itself. TRPV1 activation also triggers various downstream effects that might be beneficial for hair growth.
Key Takeaway: Capsaicin activates TRPV1, a receptor found in various tissues. TRPV1 activation seems to hamper hair growth in animal and cell culture studies, however, it may signal downstream effects that benefit hair growth.
Capsaicin and UCP2
Here’s one of the more hair-friendly results of TRPV1 activation:
Uncoupling protein 2 (UPC2) (1).
This protein is an uber-critical component of ATP energy production by cell mitochondria.
Mitochondrial energy production results in the production of damaging compounds called free radicals.
Here’s the great part:
Increased production of UPC2 results in less free radical production by mitochondria.
UCP2 proteins have been identified in human skin, suggesting they play a role in regulating skin free radical damage or oxidative stress (4).
By preventing excessive oxidative stress, enhanced UCP2 expression by TRPV1 may prevent hair loss.
Analysis of hair follicles indicates that balding dermal papilla cells (DPCs), the cells that are essential for hair growth, are more susceptible to oxidative stress than normal DPCs.
So, in theory, preventing oxidative stress in any way may help prevent hair loss.
But, no studies have been performed connecting increased UPC2 expression to hair loss prevention. So, we can’t predict just how UCP2 levels might influence hair growth or loss.
Key Takeaway: TRPV1 activation stimulates enhanced expression of UPC2 which prevents excessive free radical production by mitochondria. Considering balding DPCs are more susceptible to oxidative stress than normal DPCs, this may be helpful for hair loss prevention. But, no studies have been performed to test this.
Capsaicin and IGF-1
Another novel effect of TRPV1 activation is this:
Increased levels of IGF-1 (5).
IGF-1 is a growth factor that stimulates the division of DPCs in hair follicles (6). This means it plays a critical role in hair growth.
Interestingly, research suggests dihydrotestosterone (DHT), the main culprit behind androgenetic alopecia (AGA; pattern hair loss common in both men and women), inhibits hair growth by lowering hair follicle IGF-1 levels (7).
It works by blocking calcitonin gene-related peptide (CGRP) release, which is responsible for increasing the production of IGF-1.
Here’s where capsaicin can make a difference:
It counteracts the action of DHT by activating TRPV1 and increasing CGRP release. This stimulates the production of IGF-1.
In this way, capsaicin may stimulate enhanced hair growth.
Hint: They’ve actually performed a study on this, keep reading on to the next sections!
- TRPV1 activation increases the release of CGRP which stimulates IGF-1 production.
- IGF-1 plays a key role in DPCs proliferation and hair growth.
- Interestingly, the main factor in AGA, DHT, lowers IGF-1 by blocking CGRP release.
- Capsaicin may counteract these effects.
- In this way, capsaicin may stimulate enhanced hair growth.
Capsaicin and Nitric Oxide
Remember earlier when I mentioned TRPV1 stimulates a calcium influx in cells?
Well, this increase in calcium stimulates the production of one important enzyme:
Nitric oxide synthase (1).
This is the enzyme that synthesizes a compound called nitric oxide.
Nitric oxide is a molecule that dilates blood vessels, enhances blood flow, stimulates the creation of new blood vessels, and promotes the relaxation of muscles.
Considering blood supply is a key factor in nutrient delivery and hair growth, nitric oxide production might be essential for hair growth (8).
However, the exact role of nitric oxide in hair growth is not fully known.
Researchers do believe that it is involved with blood supply to the follicle, although they haven’t confirmed this (9).
But, nitric oxide can be a double-edged sword.
Too much of it can lead to oxidative damage, which we established can hamper hair growth.
So, in some cases, application of capsaicin may lead to excess nitric oxide and possibly damage hair follicles (10).
Let’s put the pieces together:
- Using cayenne pepper for hair growth might be beneficial in that it could enhance blood flow to hair follicles through nitric oxide production.
- However, capsaicin application may also cause excess nitric oxide production, leading to oxidative stress.
And here’s the hard thing:
There’s currently no data to pinpoint the exact concentration that might induce too much production of nitric oxide.
So, each and every time you apply cayenne pepper to your scalp, you’re risking excess nitric oxide in your hair follicles.
- TRPV1 activation leads to enhanced nitric oxide synthase expression and increased nitric oxide production.
- In the body, nitric oxide is important for stimulating blood flow. However, too much can lead to oxidative stress.
- We don’t know the exact concentration at which capsaicin might cause excess nitric oxide production.
A Controversial Viewpoint: Capsaicin, TGF-β1, and Androgenetic Alopecia
This last mechanism is slightly controversial but super interesting.
Let’s start with this:
Researchers examined the effects of capsaicin on a skin cell culture that included fibroblasts.
Fibroblasts are cells in connective tissues that are responsible for producing collagen. This is the protein essential for skin integrity.
When researchers added capsaicin to the cell culture, they observed that fibroblasts degenerated.
They determined that capsaicin could slow wound healing and was toxic to skin cells.
But, here’s the thing:
It’s called perifollicular fibrosis or scarring around the hair follicle.
The main culprit behind it is the fibroblasts who produce collagen in response to inflammation. Excessive collagen production is what causes this perifollicular fibrosis.
This is mediated by two cell components:
PPAR-γ and TGF-β1.
When PPAR-γ is activated, TGF-β1 is downregulated (12). In other words, PPAR-γ blocks the activity of TGF-β1.
TGF-β1 is a crucial regulator of fibrosis (13).
Not surprisingly, in mice who have their PPAR-γ deleted from their genetic code develop scarring alopecia (14).
This could be because of the dysregulation of TGF-β1, causing excessive fibrosis around the hair follicle.
What does this have to do with capsaicin?
Researchers have observed that capsaicin prevents liver fibrosis through the activation of PPAR-γ and inhibition of TGF-β1 (15).
Whether or not capsaicin can activate PPAR-γ in hair follicles still remains to be studied, though.
- Researchers determined capsaicin was toxic to skin cells because it caused degradation of fibroblasts.
- However, this might be beneficial in the case of perifollicular fibrosis that is a factor in scarring alopecia and AGA.
- Capsaicin has demonstrated an ability to reduce fibrosis by activating PPAR-γ and downregulating TGF-β1, a crucial regulator of fibrosis.
- Mice who have their PPAR-γ deleted from their genetic code develop scarring alopecia.
- Whether or not capsaicin can activate PPAR-γ in hair follicles still remains to be studied.
Studies on Cayenne Hair Loss Treatment
Now that we know how cayenne pepper might work, let’s dive into some actual, real-life studies.
These will tell us whether or not cayenne pepper is actually worth using.
Currently, there are two studies that look at using cayenne pepper for hair loss.
One that examines the effects of capsaicin supplementation and one that utilizes a topical capsaicin ointment.
Capsaicin and Isoflavone Supplementation
Researchers performed this study on this basis:
Capsaicin and soy isoflavones have both demonstrated an ability to increase IGF-1, which is a key player in hair growth (16).
Of 48 volunteers with hair loss, 31 received a capsaicin and isoflavone supplement while 17 received the placebo. The study ran for 5 months.
At the end of the study, 20 of 31 subjects in the active group experienced hair growth, compared to 2 out of 17 in the placebo group.
However, researchers in this study noted that soy isoflavones are more effective at promoting IGF-1 production compared to capsaicin.
So, the majority of these results could be a result of the isoflavone supplementation.
Therefore, we can’t really make a conclusion on whether or not cayenne pepper alone will benefit hair growth.
- A capsaicin and soy isoflavone supplement was more effective than a placebo at promoting hair growth.
- However, researchers on the study note that soy isoflavones are more effective at increasing IGF-1 production than capsaicin.
- So, the majority of the effectiveness could have been a result of the isoflavone supplementation.
Capsaicin Ointment for Alopecia Areata
In a randomized, placebo-controlled, triple-blind trial, researchers observed the effects of a 0.075 percent concentration capsaicin ointment for the treatment of alopecia areata (17).
Of 40 volunteers diagnosed with alopecia areata, 20 were randomly assigned to receive the capsaicin ointment while 20 received a placebo for 12 weeks.
At the end of the twelve weeks, there was no statistically significant difference between the active or placebo group.
This suggests that capsaicin is not effective for alopecia areata when used topically at a 0.075 percent concentration.
However, we don’t know if it would be more effective at a higher concentration. It also hasn’t been tested for other forms of hair loss like AGA.
- When compared to a placebo, a 0.075% capsaicin ointment was not more effective than the placebo.
- This suggests that at a 0.075% concentration, capsaicin does not effectively treat alopecia areata.
- But, we don’t know if it would be more effective at a higher concentration or if it would treat other forms of hair loss.
Popular Ways to Use Cayenne Pepper for Hair Loss
Although the research on cayenne pepper is relatively inconclusive and bare, many people still use it.
The good news is that it is lipophilic, or fat-soluble (18).
So, if the proposed mechanisms actually do work, it is easily absorbed into the skin.
But, try topical cayenne pepper at your own risk:
Research indicates that TRPV1 receptors may downregulate their production in response to continual capsaicin application (1). This could cause unwanted side effects.
Here are some of the ways cayenne pepper can be used.
Cayenne Pepper Paste for Hair Growth
A cayenne pepper paste is one way you can utilize cayenne pepper for your hair.
Although, there’s no guarantee that it will accomplish anything beyond a slight burning sensation.
But, if you really want to try a cayenne pepper paste for hair growth, here’s how to do it:
- In a mixing bowl, adding equal parts cayenne pepper and water.
- Mix together using a spoon or other mixing utensil.
- When fully combined, apply the mixture to areas of your scalp where hair is thinning.
- The longer you allow a cayenne pepper paste, the more capsaicin that will be absorbed.
- After allowing the mixture to sit, rinse and cleanse as usual.
Cayenne pepper can cause skin irritation. If you experience a painful sensation following application, rinse immediately.
Key Takeaway: There’s no guarantee that a homemade cayenne pepper paste will have any effect on hair growth.
Cayenne Pepper and Coconut Oil
Another way to incorporate cayenne pepper into your hair care routine is this:
Add it to your weekly oil masks.
Capsaicin, being lipophilic, can easily incorporate into the coconut oil.
As coconut oil is absorbed into the skin and hair follicle, the capsaicin will be absorbed along with it.
Keep in mind, though, that there’s no hard evidence to prove it will truly work for hair growth.
Key Takeaway: Cayenne pepper is great to include with your weekly coconut oil masks.
Cayenne Pepper and Apple Cider Vinegar
One of the most popular ways to use cayenne pepper is in a tonic with apple cider vinegar.
While there’s definitely no studies to back the effectiveness of consuming apple cider vinegar and cayenne pepper to promote hair growth, you can use it to potentially support overall health.
A healthy body is important for sustaining healthy hair.
Here’s how to make it:
- In 8oz of water, add 1 tbsp of organic apple cider vinegar with the mother.
- Add a pinch of cayenne pepper to the tonic and stir to evenly distribute the cayenne pepper.
- Optional: Add a drop or two of organic, raw, unfiltered honey, a squeeze of lemon, and a few ice cubes.
The tonic is surprisingly tolerable!
Key Takeaway: There are no studies available that can tell us how consuming apple cider vinegar and cayenne pepper tonics could benefit hair growth. However, it may support overall health which is important for sustaining healthy hair.
Cayenne Pepper for Hair Growth: Is It Worth It?
Here’s the verdict:
The research on cayenne pepper for hair growth is mixed and inconclusive.
There are some proposed mechanisms that seem really promising.
But, there’s no hard evidence that demonstrates whether these mechanisms work in a live human setting.
So, we can’t say whether or not cayenne pepper will promote hair growth.
If you still choose to use it, keep in mind that continual use may have a negative impact on cells. TRPV1 receptors might downregulate as an adaptation.
What do you think about cayenne pepper for hair loss? Are you still planning on using it? Let me know in the comments below.