Caffeine is an Immunomodulator
Caffeine appears to have an anti-inflammatory effect in some situations and helps calm down an “overactive” immune system. In animal (rodent) models, it’s quite clear that caffeine can affect a variety of different types of inflammation. The effects on humans appear similar, with caffeine having an effect on multiple parts of the immune system – particularly immune cells known as lymphocytes.
To date, there is good evidence to suggest a suppressive effect of caffeine on the proliferation of “stimulated” lymphocytes. In other words, immune cells that have become too active can be quieted down with caffeine. Other immune cells such as natural killer cells and macrophages also exhibited a reduced activity in the presence of high doses of caffeine.
Caffeine may also be truly Immunosuppressive in some situations given the reduced levels of anti-inflammatory cytokines such as TNF-α, IL-2 and IL-6. Moreover, certain receptors, such as TLR1, TLR2, TLR4, and MHC class I-related chain B molecules are also decreased by caffeine.A recent study showed that caffeine inhibits STAT1 signaling and downregulates inflammatory pathways involved in autoimmunity.
Caffeine is a widely consumed pharmacologically active product. We focused on characterizing immunomodulatory
effects of caffeine on peripheral blood mononuclear cells. Caffeine at high doses showed a
robust downregulatory effect on cytokine activity and genes related to several autoimmune diseases including
lupus and rheumatoid arthritis. Dose-dependent validation experiments showed downregulation at the mRNA
levels of key inflammation-related genes including STAT1, TNF, IFNG, and PPARG. TNF and PPARG were
suppressed even with the lowest caffeine dose tested, which corresponds to the serum concentration of caffeine
after administration of one cup of coffee. Cytokine levels of IL-8, MIP-1β, IL-6, IFN-γ, GM-CSF, TNF, IL-2, IL-4,
MCP-1, and IL-10 were decreased significantly with caffeine treatment. Upstream regulator analysis suggests
that caffeine inhibits STAT1 signaling, which was confirmed by showing reduced phosphorylated STAT1 after
caffeine treatment. Further studies exploring disease-modulating potential of caffeine in autoimmune diseases
and further exploring the mechanisms involved are warranted.
In actual human epidemiologic studies, coffee has mixed effects. Caffeine (coffee) consumption appeared to increase the risk of developing type 1 diabetes and rheumatoid arthritis. In contrast, coffee may help somewhat to prevent ulcerative colitis and multiple sclerosis. There does not appear to be an association ether way for other autoimmune diseases such as systemic lupus erythematosus, psoriasis and Crohn’s disease.
In the world of hair loss, there are very few studies which have objectively examined the benefits of caffeine. Some studies have suggested a minor benefit for caffeine containing shampoos but these studies are small and have not yet been independently replicated to any significant degree.
It is fascinating to consider that caffeine has the potential to effect so many parts of our immune system. More studies are needed to understand whether or not caffeine can integrate into the treatment of various types of hair loss.
The cultivated hair follicles were split into three groups: control (which contained various levels of testosterone), caffeine (which contained various levels), and both (cultivated in testosterone first, and then cultivated in caffeine in various concentrations).
After a period of 120 – 192 hours, the follicles were removed and researchers studied hair shaft length to determine efficacy of caffeine:
As shown above, the longer the follicle was exposed to caffeine, the longer the hair shaft became. There was even a slight difference in the elongation effects of the two different concentrations (0.001% and 0.005%), though it’s quite negligible.
However, this wasn’t the only thing that researchers found.
Surprisingly, hair follicles that were exposed to caffeine even after exposure to testosterone showed positive (and significant) elongation:
Addition of caffeine in amounts as small as 0.001% were found to counteract the suppressive effects of testosterone on hair growth, with higher shaft elongation achieved compared to the control group.
It Stimulates Hair Growth
Even more than just suppressing the effects of DHT, caffeine has been shown to actually stimulate hair growth in human hair follicles. Let’s take a closer look at the research behind this intriguing finding.
Whole human hair follicles were extracted from the scalps of both men and women. The men were confirmed to be a stage III to stage IV on the Norwood-Hamilton scale, while the women were ‘normal’.
After a 24-hour ‘recovery time’, the hair follicles were cultivated in one of three mediums:
- Testosterone only;
- Testosterone + caffeine; or
- Normal medium (as a control).
The total culture time was 120 hours.
So, what did this study teach us?
Caffeine Enhanced Hair Shaft Elongation
Just as the previous study showed, the presence of caffeine even after the hair follicle has been exposed to testosterone can elongate the shaft.
Interestingly, this elongation was shown to be different between men and women.
In the previous study, concentrations of caffeine as low as 0.001% were found to be effective in counteracting the effects of testosterone. However, these were shown to be too high for women, and the concentration was lowered to 0.0005%. This proved to be beneficial, and results were shown to be similar to those of male hair follicles.
Caffeine Prolonged Anagen Phase
There are three stages within the hair growth cycle:
- Anagen (active growth);
- Catagen (transition); and
- Telogen (rest).
In men and women with AGA, the process of follicle miniaturization shortens the anagen phase. This results in less hair growth.
By prolonging anagen phase, the effects of DHT (which trigger miniaturization) can be counteracted.
As shown by researchers, this is exactly what caffeine was able to do:
When exposed to testosterone, the percentage of male and female hair follicles in anagen phase reduced dramatically (to 39% and 55%, respectively). When conincubated with caffeine, though, these percentages raised to 70% in men and to 63% and 65% in women.
This shows that caffeine can not only suppress DHT, but it can also make it possible for the hair follicles to function even in its presence.
Caffeine Stimulated Hair Matrix Keratinocyte Proliferation
The hair follicle is a complex organ, containing multiple parts that work together to produce hairs from the skin. One major component of the follicle is the hair matrix, which is where the hair shaft (and the inner and outer root sheaths) are actually produced.
Within the matrix are cells tasked with producing keratin, the protein that makes up the majority component of hair.
One major finding within this study was that caffeine actually stimulated the proliferation of keratinocytes.
The above shows an increase in the presence of Ki-67, a protein that marks cellular proliferation. As the concentration of caffeine goes up, so too does the amount of Ki-67 present within the follicles.
What does this mean for hair growth?
If keratin is necessary for the growth of hair, then an increased presence of keratin-producing cells can be beneficial during the anagen phase of hair growth. This can lead to more hairs being produced over time.
It Can Be Absorbed Through the Scalp
Caffeine can be absorbed through the scalp! Amazing, right?
Skin Pharmacol Physiol. 2007;20(4):195-8. Epub 2007 Mar 29. Follicular penetration of topically applied caffeine via a shampoo formulation. Otberg N1, Teichmann A, Rasuljev U, Sinkgraven R, Sterry W, Lademann J.
AIMS: Follicular drug delivery is the prerequisite for an effective treatment of androgenetic alopecia or other reasons of premature hair loss. METHODS: The follicular penetration of caffeine, applied topically in a shampoo formulation for 2 min, was measured with highly sensitive surface ionization in combination with mass spectroscopy, a selective method for the detection of very small quantities of transcutaneously absorbed substances in the blood. An experimental protocol, developed to selectively block the follicular pathway within the test area, was used. Based on this principle, a clear distinction between interfollicular and follicular penetration of topically applied caffeine was feasible. RESULTS: After 2 min, caffeine penetrated via the hair follicles and stratum corneum. CONCLUSION: It was found that the penetration via hair follicles was faster and higher compared with the interfollicular route and that hair follicles are the only pathway for fast caffeine absorption during the first 20 min after application.
But how did this discovery come to be?
Researchers from Berlin, Germany and Tashkent, Uzbekistan recruited six healthy, Caucasian men to take part in their study. The goal was to determine the ability of caffeine to penetrate the skin and absorb into the hair follicles.
The six volunteers underwent two separate experiments, which took place one week apart:
- In the first experiment, a shampoo with caffeine (1%) was applied to a test area on their chest. The follicles in this area remained open.
- In the second experiment, a shampoo with caffeine (1%) was applied to a test area on their chest. The follicles were then closed with a varnish-wax mixture.
Each volunteer had their caffeine levels tested via blood test before beginning.
The shampoo was washed away after two minutes, and blood samples were taken at 5, 10, 20 and 30 minutes, as well as 1, 2, 5, 8, 24 and 72 hours after the caffeine shampoo application.
In the first group, it was found that caffeine levels could be detected in the blood as early as five minutes post application. The concentration showed at 6.3 ng/ml.
In the second group, though, caffeine levels were only detected once 30 minutes had passed. Researchers theorized that the inability to permeate the follicles significantly slowed its absorption (as its only way through was the skin).
This shows that, when in the presence of follicles, caffeine is able to be significantly absorbed. This makes it a great addition to shampoos, which is why I included it in my own Grogenix line.
What Amount of Caffeine is Healthy for Your Hair?
Scientists estimate that you’d have to consume about 60 cups of coffee (the main source of caffeine) for you to ensure that the amount reaching the hair follicles is significant.
However, that would be a detriment to your body and would put you at risk of a heart attack. It is also known to be addictive: if you take more than two cups a day, you can form a dependence and might experience headaches, anxiety, or even depression.
So, instead of taking caffeine in the form of drinks, a caffeine-rich solution rubbed on your scalp would be the best treatment for your hair. Luckily, there are caffeinated shampoos out there that you can readily buy.
Moreover, you can make your own coffee oil shampoo at home.
A Simple Coffee Oil Shampoo
Coffee grounds can be dried and infused into oil which can be rubbed on the scalp either directly or when combined with pre-made shampoo treatments and leave-in conditioners.
- Green or roasted whole coffee beans (3 ounces)
- Coconut oil (3 cups)
- Pour the coconut oil into a small glass crock pot
- Add the 3 ounces of coffee beans
- Cover the beans and the oil and cook for approximately 5-6 hours over a slow heat. Regular checks might be necessary to ensure the oil and the beans do not burn up. Be sure to stir the mixture every half hour or so.
- When the mixture is cooked, turn off the crock pot and use a paper coffee filter to strain the oil and remove the beans, which can now be disposed.
- Pour the oil into a clean container, ready for use.
- Apply the oil directly to the scalp, either on its own or combined with shampoo and leave it for 5-8 minutes.
- Rinse thoroughly with plenty of cold water.
There is overwhelming evidence that strongly suggests caffeine is a good natural product for your hair.
Besides helping you to fight off scalp conditions like androgenetic alopecia, caffeine can help grow your hair quickly and also improve its vitality.
Its ability to penetrate the scalp pretty easily makes it a good addition to your favorite hair shampoo.