There has been a lot of chatter about using green tea to reduce hair loss, and as a potential DHT blocker. In this article I’ll review the scientific evidence to see if you should be adding green tea to your daily supplement list.
Green tea was originally grown in China, but now is grown in other places as well. It can be used either as a drink or an extract. The claims about what makes green tea effective is that it contains polyphenols and flavonoids.
The percentage of flavonoids in green tea is higher than can be found in most vegetables, fruits, or wine, all of which have fairly large amounts.
(Learn more about vitamins and the role they can play in hair growth here!)
It is packed full of things that are recommended to improve the overall quality of your health, and possibly the quality of your hair.
What Could Make Green Tea Work?
Many people who have used green tea to reverse their hair loss problems attribute the effects to the high levels of antioxidants. Other ways in which it could contribute to hair regrowth and prevention of hair loss are:
- Improves circulation of hormones and improves blood flow (4).
- Helps inhibit testosterone production and interferes with the conversion to DHT (5).
- Contains a potent antioxidant called EGCG (6).
Fortunately, there are scientific studies which seem to back these claims.
Is There Scientific Evidence that Green Tea Can Help with Hair Loss?
Let’s look at a few studies which highlight the benefits of green tea as it directly (and indirectly) relates to hair loss.
Saitama Prefecture, Japan
Researchers from the Saitama Cancer Center have published a paper that showed that a particular cytokine, the Tumor Necrosis Factor alpha, has effects on the hair and can result in hair loss (7).
Green tea is able to suppress the production and development of TNF-alpha, which as a result might make it a cure for hair loss (8).
Additionally the paper included information on hair growth as a result of drinking a lot of green tea and the effect this has on DHT, the latter being linked to baldness and hair growth in puberty.
California, USA (2005)
A more direct study was performed in 2005, and it tested the effects of drinking green tea (and more specifically, it’s polyphenic compounds) on hair growth in mice (9).
The mice recruited for the study were all female, and all had suffered spontaneous hair loss on the head, neck, and dorsal regions. The 60 mice were split into two groups:
- Group A received 50% fraction of polyphenol extract from dehydrated green tea in their drinking water for six months; and
- Group B received regular drinking water.
Otherwise, both groups of mice were fed the same diet, and lived in similar environments.
At the end of the study, researchers found that 33% of mice in Group A had significant hair growth during the six months of treatment.
No hair growth at all was seen in Group B, the control group.
Massachusetts, USA (2003)
Prostate cancer isn’t often discussed, but its incidence is concerning. In fact, 1 man out of every 9 will be diagnosed with it in their lifetime.
With this in mind, researchers from Boston, Massachusetts decided to investigate the factors that reduce the prevalence of prostate cancer in Asian countries. To start, they looked at diet.
Soy products and tea (such as green and black) are consumed much more regularly in Asia than other parts of the world. As such, researchers focused on these products (and their compounds), to determine if they had an impact on androgen-sensitive human prostate cancer (as studied in mice) (11).
Ninety-six mice were used in this study, and they were split into six groups:
- Soy Phytochemical Extract (SPC);
- Black tea;
- Green tea;
- SPC and black tea; and
- SPC and green tea
The mice were inoculated with human prostate cancer cells, and serum PSA levels were taken at four and eight weeks to determine tumor-take rate and tumor size. At the end of the 10-week study, the tumors were excised and weighed and blood samples were taken. These were the results:
The results show that all groups except the control and green tea group, significantly reduced final tumor weight. Green tea alone did reduce final tumor weight by 22%, but not as drastically as the other active groups.
Overall, the combination groups (SPC + black tea and SPC + green tea) performed best. They reduced final tumor weight by 93% and 88%, respectively.
Serum levels of DHT were also taken, which is what we’re most interested in.
The black tea treatment group had greater serum testosterone concentrations (34.4%) and 72% lower DHT concentration than control. This suggests that black tea may contain components that inhibit 5AR.
On the other hand, green tea increased serum testosterone and DHT levels by 73.8% and 194%, respectively. The combination of SPC and green tea did reduce DHT levels, though.
So, what does this mean?
Interestingly, this study contradicts the results of the previous two studies. However, further research should be carried out before any final conclusions.
A common theme in the research is that green tea’s antioxidant and anti-inflammatory properties seem to be very important in supporting the growth of new hair by supporting overall health.
Here’s my article on theaflavin extract for hair loss.
In order to get the daily recommended dose of 250 mg of catechins, one needs three to five cups of green tea per day. The supplement form (extract) should not be taken on an empty stomach because there is some concern over liver injury (hepatotoxicity) (12).
It is unlikely for this to occur when drinking the leaves brewed as a tea, but the extract form is much more potent.
There doesn’t seem to be an established recommended amount of how many milligrams per day are needed to improve hair growth, but three to five cups of tea per day is considered safe for most adults unless you have an underlying liver problem.
If you do have liver issues you should speak to your physician before using green tea for hair regrowth. A high dosage is defined as 10 to 29 milligrams of green tea extract per kilogram of body weight per day.
Are There Any Known Side Effects Of Green Tea?
There have been no reported cases of toxicity from people who drink green tea. Toxicity can occur when using green tea extract, though.
Green tea leaves contain polyphenols, and EGCG has the highest concentration of all the polyphenols (13).
This doesn’t cause any problems if you’re just drinking the tea, but an extract taken as a supplement contains a much higher concentration than just hot brewed tea.
It has been documented that high doses of EGCG can lead to liver damage and aggravate any existing liver problems (14).
As such, green tea extract should be taken with food and never on an empty stomach.
If you are using green tea extract and develop any symptoms associated with liver damage (abdominal pain, unusual colored, dark urine, or if you develop signs of jaundice), discontinue using it and see your doctor.
The Correlation Between Green Tea and DHT
Dihydrotestosterone is a sex steroid and androgen hormone (15). It is synthesized from testosterone in three different places in the body: the testicles, the prostate, and the hair follicles.
DHT is also the main culprit when it comes to gradual, natural hair loss.
The problem is that this hormone basically sticks to the follicle and piles up on it, slowly suffocating the hair follicle. When that happens, hair loss is not far behind.
Luckily the process is usually reversible and once the problem is handled, the hair often grows back.
In this case, the enzyme that is responsible for the storage of dietary fat.
That is the main reason why green tea is so popular among dieters, and it does have some medically proven qualities that can actually play a big part in the fat loss process.
But perhaps even more important than its role as an enzyme inhibitor is its ability to blunt androgen receptor function (18).
Androgen hormones, such as DHT, connect to the hair follicles via androgen receptors. For most people, this is fine; however, those with androgen sensitivity will experience symptoms that lead to miniaturization of the hair follicle.
If green tea blunts androgen receptor function, then logically it can help to reduce the sensitivity of the follicles.
Could It Actually Effect Testosterone?
The compounds in green tea can inhibit aromatase too, which is an enzyme that turns androgens (male hormones like testosterone) into estrogen (19).
Contrary to the popular belief, men do have estrogen in their bodies, just as women have testosterone.
There is research out there which suggests that green tea’s compounds could inhibit 5-alpha reductase, the very compound that can synthesize DHT, the hormone that causes male pattern baldness (20).
The reason why many people question the legitimacy of that study, is the fact that the subjects drank a ridiculous amount of green tea, which would be practically impossible in real life, at least in the long run.
There are also scientists that suggest that consuming small amount of green tea could actually have the opposite effect, increasing the level of DHT, which is not a good thing when it comes to natural hair loss.
The studies seem to suggest that drinking excessive amounts of green tea can reduce testosterone levels, while small amounts can increase it.
How Can You Get More Green Tea into Your Diet?
In order to get real, measurable benefits from green tea, you will need to use it consistently and daily. It is recommended that you use it at least twice daily, in some form.
Brewing the tea leaves is the most common way of consuming it.
Depending on the quality of the leaves, brewing time can vary. If you use high quality leaves, they can be steeped in water that is less hot (about 69 degrees Celsius, 160 degrees Fahrenheit), for about 30 seconds.
If you’re using “spent” leaves (lower quality), the brewing time needs to be a bit longer-the recommended time is two to three minutes, at 87 degrees Celsius, which is 190 degrees Fahrenheit.
Some people drink a more concentrated version of green tea which is called matcha tea. Matcha tea is essentially finely powdered green tea leaves. Since the leaves are powdered down they can be drunk. Drinking the tea leaves gives you higher doses EGCG, and is pretty similar to taking the extract as a supplement.
However the caveat to drinking matcha tea is you may get higher concentrations of caffeine and any other heavy metal contaminants like lead or arsenic present in the tea leaves. Consequently it’s important to drink high quality matcha that is carefully sourced and free of heavy metal contamination.
The majority of people tend to consume 1-2 servings of matcha a day, which is the equivalent to around 10-20 cups of regular green tea.
Green Tea versus Finasteride: Which Is the Best DHT Blocker?
Green tea is a natural compound that may lower DHT levels and even blunt androgen receptors at the hair follicles. But how does it compare to the FDA-approved hair loss drug finasteride?
However, an interesting side effect was that of hair growth.
As such, finasteride was soon evaluated as a hair loss treatment and eventually released under the name of Propecia.
But how does it work? Actually, it works quite similarly to green tea.
Finasteride is foremost an inhibitor of type II 5-alpha-reductase (23). This thereby reduces serum and scalp DHT by inhibiting conversion of testosterone to DHT.
And its been proven in numerous studies over the past two decades.
One of the first studies on the drug determined that:
“In men with male pattern hair loss, finasteride 1 mg/d slowed the progression of hair loss and increased hair growth in clinical trials over 2 years.”
There have also been numerous studies since then, including one that took place over five years (24).
So, which is the best: green tea, or finasteride?
The answer isn’t quite so simple, as there haven’t been any studies that directly compare green tea and finasteride.
However, it is much easier to get a therapuetic dose of finasteride than it is to consume multiple cups of green tea on a regular basis. After all, as little as 1 mg of finasteride has been shown to be effective in reducing hair loss (and even inducing growth).
We’ve learned that green tea contains high levels of polyphenols and flavonoids. Flavonoids and an antioxidant called EGCG are what make green tea effective in boosting the immune system (25).
The reviews on the efficacy of green tea are mixed, but overall there seem to be more positive outcomes than negative ones.
It has also been demonstrated that the use of green tea increases metabolism and contributes to improvements in a person’s general health and well-being but no firm evidence has shown it to be valuable enough to add to a daily hair care regime (26).
Though, if you want an easier (and scientifically proven) way to combat hair loss, then you may also want to consider finasteride.