This post may contain affiliate links, which means I'll receive a commission if you purchase through my link, at no extra cost to you. Please read the full disclosure here.
Is Saw Palmetto actually effective in treating hair loss? What's the Saw Palmetto hair loss dosage being used for treatment in the clinical studies for androgenic alopecia?
In this blog post we will investigate the above questions. You may have heard of Saw Palmetto before...This shrub like palm tree is native to the Southeastern United States and has a crown of thorn-shaped leaves that are arranged like a fan along with oblong shaped berries (1).
The botanical extract prepared from its berries is thought to have anti-androgenic effects. You know in this blog we love anything anti-androgenic. So naturally I was interested...Get it? Naturally? Like this is a natural remedy for hair loss... lol.
Anyways...Moving on...
I've seen it being toted as an anti-inflammatory and doing a quick google search I found tons of information about Saw Palmetto being investigated as a treatment for improving urinary tract symptoms associated with prostate enlargement in men...
(Apparently the metabolism of dihydrotestosterone (DHT) via the enzyme 5-alpha reductase is also key to the onset and progression of benign prostatic hyperplasia (BPH) (2).
Who knew?
But in this post we will take a look at some of the published studies which report on the efficacy, tolerability and safety of these supplements and topicals for the treatment of hair loss. I will also highlight the saw palmetto for hair loss dosage being used in the supplements reported in these studies.
I want to highlight that in my opinion not all Saw Palmetto dosages are created equal. The method of extraction of saw palmetto may impact the levels of bio-activity around 5α-reductase inhibition. I discuss this more below...
First Let's Get Acquainted...Some Background On Saw Palmetto...
Saw palmetto (SP) is a botanical extract from the berries of the Serenoa repens dwarf tree (1).
The mechanism of action is thought to be similar to that of finasteride. Finasteride is one of the drugs that is FDA approved to treat androgenic alopecia in men by 5α-reductase inhibition.(5α-reductase converts testosterone to dihydrotestosterone (DHT) which is thought to play a role in hair follicle miniaturization) (1). Saw palmetto is also thought to be an inhibitor of 5α-reductase (1).
Saw Palmetto is also thought to decrease DHT uptake by the hair follicle and decrease the binding of DHT to androgenetic receptors (1)
The botanical extract has been evaluated for the treatment of conditions like benign prostatic hyperplasia, migraine, chronic pelvic pain, androgenic alopecia, telogen effluvium, seborrheic dermatitis, facial sebum, and more (1,6).
For medicinal purposes it has been used in both oral and topical formulations (1).
Saw Palmetto is thought to have minimal side effects and low drug interaction potential (1).
As discussed earlier, Saw Palmetto extraction methods may impact the levels of bio-activity around 5α-reductase inhibition. So when we're looking at the data in the studies below keep in mind that these studies may be using Saw Palmetto supplements with different extraction processes which may make it difficult to assess how potent one Saw Palmetto supplement is compared to another, (Even if their milligrams per pill are listed as the same). (Check out this paper linked HERE for more on Saw Palmetto extraction techniques and their impact on the Saw Palmetto pharmacological profile (8)). I discuss this further along with the extraction method I'd look for when purchasing a supplement in the "Sum it all up" section at the end of this post.
Talk Data To Me...
Let's take a look at some of the studies which have investigated saw palmetto and its effects on hair loss.
To my knowledge the first study I discuss is the largest to date. This is an open label study with a treatment period of 24 months. This study enrolled 100 male patients with clinically diagnosed mild to moderate androgenic alopecia (AGA).
You can stalk the study HERE
What was the saw palmetto hair loss dosage used?
Group 1: Serenoa repens--(Saw Palmetto containing tablets) 320 mg every day for 24 months
Group 2: Received Finasteride 1 mg every day for the same period
How was efficacy assessed? 3 expert dermatologists in alopecia essentially used a scoring system based on the comparison of the global photos taken at the beginning of the study and at the end (T24) of the treatment.
What did the results show?
68% of patients treated with finasteride had higher hair density scores from baseline as compared to 38% of the SP group (p < 0.05). So this would mean that Saw Palmetto was inferior to finasteride.
Something else to note was that neither finasteride or saw palmetto was reported to be clinically effective in 10% of the patients. It was also noted that saw palmetto did stabilize the progression of AGA in 52% of cases.
It was also clinically observed, that finasteride acts in both the front area and the vertex of the scalp, while the Saw Palmetto containing tablet mostly acted in the vertex of the scalp (3).
This next study aimed to investigate the safety and efficacy of a food supplement containing L-cystine, Serenoa repens, Equisetum extract, zinc, and vitamins (Lambdapil® Anti Hair Loss capsules, ISDIN, Provençals, Barcelona, Spain) in improving hair loss in both women and men. I have linked the supplement HERE and you can also find it linked in the image below.
(So essentially the Saw Palmetto---(serenoa repens) was part of this anti-hair loss supplement formulation).
You can stalk the study HERE.
The study population included:
70 people total--(35 men and 35 women)
23 men received the anti-hair loss capsule containing saw palmetto. 12 received placebo
23 women received the anti-hair loss capsule containing saw palmetto. 12 received placebo. 1 woman in the treatment group discontinued treatment due to bloating symptoms
Men with androgenic alopecia and women with acute telogen effluvium. They were randomized to receive two capsules per day of the saw palmetto containing anti-hair loss supplement or the placebo product during a 6 months treatment period.
What was the saw palmetto for hair loss dosage in the treatment group being used in this capsule?
100 mg per 2 capsusles (They took these two capsules at the same time with breakfast)
How was the efficacy measured?
Essentially digital images were taken evaluating hair volume and appearance which were assessed by dermatologists through a 7-point clinical score scale.
Some of the other efficacy measures were done by the participants in the study completing a self-assessment survey regarding how they perceived the results of their treatment.
What did the results show?
In women, the number of hairs removed in the pull test decreased earlier for the group taking the saw palmetto containing capsule over the 6-month period with a significantly greater decrease (p<0.05) for the treated group compared to the placebo group
For men, the anagen/telogen ratio increased in the Lambdapil® treated group by 22.3% over baseline. (This would indicate that there were more hairs in the growing phase vs. placebo treated group (p<0.05).
The hair volume was also reported to have improved at 1, 3 and 6 months significantly more in the Saw palmetto capsule containing group than compared to the placebo group (p<0.05).
The participants also reported increased hair volume, improved quality of life, and enhanced self-perceived efficacy while on the saw palmetto containing anti-hair loss tablet (4).
The authors also concluded that the treatment was well tolerated.
Next up is a study that was actually conducted in women...Woooo! You know I love that!
This study was a six-month, randomized, double-blind, placebo-controlled study evaluating the safety and efficacy of a nutraceutical supplement (Nutrafol) for promoting hair growth in women with self-perceived thinning hair.
So not necessarily androgenic alopecia... (self perceived thinning)
I've linked the product HERE but you can also find it linked below.
You can stalk the study HERE.
26 women were in the Nutrafol group and 14 women were assigned to placebo.
What was the saw palmetto dosage for treatment being used to combat hair loss?
This is where it gets a little tricky. The Saw Palmetto was part of their "Patented Synergen Complex" where it was described as: Saw Palmetto CO2 Extract (>45% fatty acids). (We discuss CO2 extract more in the sum it all up section).
The authors concluded that taking this supplement daily resulted in a significant increase in the number of terminal and vellus hairs in the target area at day 90 and day 180 vs placebo.
It was also reported that there were significant improvements in hair growth and hair quality. A significant percentage of subjects receiving the Nutrafol treatment also reported improvement in hair growth, volume, thickness, and hair growth rate, as well as decreased anxiety and other wellness parameters (5).
There were no reported adverse events.
Saw Palmetto Topical Application...
This study assessed the efficacy of a topical Saw Palmetto-containing lotion applied to the entire scalp daily for the treatment of androgenic alopecia in 50 men. The participants also applied a concentrated Saw Palmetto containing serum dedicated to thinning areas of the scalp for the first 4 weeks (6).
There was no control group for this study.
You can stalk the study HERE.
Some results that stood out to me were:
The Norwood scale was used to measure the extent of male pattern baldness and was taken at baseline.... (So before the treatment started.) The median androgenic alopecia stage changed from 4 at baseline to 3 at 24 weeks. I've linked an image of the Norwood scale HERE in case you were curious about the scale and wanted to see what number 3 and 4 look like.
The authors reported a slight increase of hair over the anterior and vertex scalp and higher patient satisfaction scores were noted at the end of the study.
More on Saw Palmetto Topical Application...
For topical application: Saw Palmetto is diluted in carrier oils and then massaged into the scalp... I've linked my favorite scalp massager below. For more information on scalp massage as a way to combat hair loss check out my post HERE which also includes how I use this massager. In the study above some of the additional ingredients in this lotion were things like peony root, oligopeptides, green tea extract...
Any Side Effects/ Safety Concerns With Saw Palmetto?
The most commonly reported side effects with the use of oral Saw Palmetto for alopecia are mild and most commonly gastrointestinal in nature, including nausea, constipation, and diarrhea (1).
Applying saw palmetto extract topically has been associated with minor side effects like cold sensation, mild burning, unpleasant smell, itchy scalp, acne on the forehead, and allergic contact dermatitis (1).
What about use in men and women of child bearing potential? You should always consult your physician for a specific recommendation. In some of the clinical trials I was reading, women were excluded from the study if they were pregnant, were trying to become pregnant, or lactating. I found one resource that said it may be unsafe to use while pregnant or breastfeeding (7).
Sum It All Up...My Thoughts on Saw Palmetto Hair Loss Dosage Being Used For Treatment... Along With What Extraction Method I Would Search For In A Supplement...
I think Saw Palmetto may have some modest effect on hair regrowth in androgenic alopecia and telogen effluvium but we need more randomized clinical trials to really be able to confirm. We don't have a ton of data to work with here and so the clinical evidence regarding the efficacy of Saw Palmetto containing products to treat hair loss is very limited. (Keep in mind I'm just discussing a few of the studies in the scientific literature and I encourage you to do your own research as well)
The Saw Palmetto hair loss dosage for treatment being used for oral supplementation in the studies that I reviewed were around 200-320mg daily dose
In the only head-to-head study comparing Saw Palmetto containing tablets to finasteride the results did show moderate efficacy in hair regrowth in the Saw Palmetto group...But...Overall the outcomes were still inferior to finasteride.
When choosing a supplement or deciding on topical application you may want to consider the way that Saw Palmetto is being extracted because this may impact how well it inhibits 5a-reducatse (the enzyme responsible for converting Testosterone to DHT). I think this is super critical and many of the supplements don't actually list how the Saw Palmetto is being extracted
So what extraction method would I look for when searching for a supplement? This is just my opinion. But I found a paper discussing a novel saw palmetto supercritical CO2 extract (SPSE) for 5α-reductase inhibition (9). In the study Saw Palmetto supercritical CO2 extraction was tested against Finasteride, the approved 5α-reductase inhibitor as positive control, which led to 63%–75% inhibition of 5α-reductase type II. Stalk the study HERE. Just for some background without getting too technical 5α-reductase type II is found in the outer root sheaths of hair follicles (10). The inhibition of this enzyme therefore may reduce hair thinning. For more details about Finasteride and the mechanism of action behind this drug, check the info I've linked HERE.
For a table assessing different Saw Palmetto Supplement brands along with a list of their extraction techniques used in BPH studies check out the link HERE. Unfortunately I couldn't find a table like this for studies in hair loss but in this table you can find brands using supercritical CO2 extraction.
Lots of the current formulations containing Saw Palmetto also contain other vitamins, minerals, or chemical additives. So this makes it difficult for us to know exactly what is doing what... What is saw palmetto's actual contribution to the clinical findings?
These studies are small and the population being assessed is mostly in men. There's also different endpoints being used to determine efficacy. There's also different extraction methods being used by different supplements. also the studies we looked at were in androgenic alopecia, perceived hair thinning, and telogen effluvium... So pretty much all over the place... There isn't s set protocol for treatment in androgenic alopecia that has been established in the literature.
Some of these studies have been sponsored by pharmaceutical companies, which does make you wonder if there could be bias when evaluating results?
Hopefully some of this data has helped you to make a determination if Saw Palmetto could be right for you. Again be sure to discuss any treatment changes you'd like to implement with your physician.
Thank you for reading! Be sure to subscribe to make sure you never miss a post!
Sending all the love to my hair loss community! You are not alone!
XOXO
-Riley
References:
1. Evron E, Juhasz M, Babadjouni A, Mesinkovska NA. Natural Hair Supplement: Friend or Foe? Saw Palmetto, a Systematic Review in Alopecia. Skin Appendage Disord. 2020 Nov;6(6):329-337. doi: 10.1159/000509905. Epub 2020 Aug 23. PMID: 33313047; PMCID: PMC7706486.
2. Prager N, Bickett K, French N, Marcovici G. A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia. J Altern Complement Med. 2002 Apr;8(2):143-52. doi: 10.1089/acm.2002.8.143. Erratum in: J Altern Complement Med. 2006 Mar;12(2):199. PMID: 12006122.
3. Rossi A, Mari E, Scarno M, Garelli V, Maxia C, Scali E, Iorio A, Carlesimo M Int J Immunopathol Pharmacol. 2012 Oct-Dec; 25(4):1167-73.
4. Narda M, Aladren S, Cestone E, Nobile V. Efficacy and safety of a food supplement containing L-cystine, Serenoa repens extract and biotin for hair loss in healthy males and females. A prospective, randomized, double-blinded, controlled clinical trial. J Cosmo Trichol. 2017;3((127)):2.
5. Ablon G, Kogan S. A Six-Month, Randomized, Double-Blind, Placebo-Controlled Study Evaluating the Safety and Efficacy of a Nutraceutical Supplement for Promoting Hair Growth in Women With Self-Perceived Thinning Hair. J Drugs Dermatol. 2018 May 1;17(5):558-565. PMID: 29742189.
6. Wessagowit V, Tangjaturonrusamee C, Kootiratrakarn T, Bunnag T, Pimonrat T, Muangdang N, Pichai P. Treatment of male androgenetic alopecia with topical products containing Serenoa repens extract. Australas J Dermatol. 2016 Aug;57(3):e76-82. doi: 10.1111/ajd.12352. Epub 2015 May 25. PMID: 26010505.
7. https://www.nccih.nih.gov/health/saw-palmetto
8. De Monte, C., Carradori, S., Granese, A. et al. Modern extraction techniques and their impact on the pharmacological profile of Serenoa repens extracts for the treatment of lower urinary tract symptoms. BMC Urol 14, 63 (2014). https://doi.org/10.1186/1471-2490-14-63
9. Pais, Pilar et al. “Determination of the potency of a novel saw palmetto supercritical CO2 extract (SPSE) for 5α-reductase isoform II inhibition using a cell-free in vitro test system.” Research and reports in urology vol. 8 41-9. 21 Apr. 2016, doi:10.2147/RRU.S96576
10. Zito PM, Bistas KG, Syed K. Finasteride. [Updated 2021 Dec 18]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK513329/