Saw Palmetto (serenoa repens) is actually a palm tree in the Arecaceae family and also comes with the name sabal or palmera de Florida. Studies have shown that saw palmetto has similar properties to finasteride, a drug used for enlarged prostate and more an dmore, for hair loss.
Several promising looking topical hair loss treatments containing powerful natural DHT blockers have been introduced to the market in recent years. Here are a few good examples:
Saw Palmetto vs Finasteride
the saw palmetto group experienced a distinct increase in hair growth
A study showed that men receiving saw palmetto had moderate response to the treatment versus men receiving finasteride. Even though the finasteride effect was higher, the study concluded that the saw palmetto induced suppression was statistically significant. (Marks et al.,2001)
Another study (Rossi et al., 2012) was conducted to determine how effective saw palmetto was for hair loss prevention and compared its effects with finasteride. The researchers used 100 male patients that were diagnosed with mild to moderate androgenetic alopecia. The patients were split into two groups, one received saw palmetto(320 mg) and the other received finasteride (1mg).
The researchers concluded that the saw palmetto group experienced a distinct increase in hair growth. When compared with the finasteride group, those treated with saw palmetto didn’t have spectacular results. Another difference between the two was the fact that finasteride acted both in the front area and the vertex while saw palmetto acted mostly in the vertex.
Although both studies show that finasteride is superior when it comes to treating hair loss, the fact that saw palmetto’s results are comparable with the drug is noteworthy. The mechanism behind saw palmetto’s effects on the scalp was not conclusive and further study was required to see exactly how saw palmetto works.
How does saw palmetto reduce hair loss?
The extract that is often used as a hair loss treatment is produced from the fruits of the plant which contain a wide array of beneficial elements: flavonoids, fatty acids, plant sterols, etc., which may account for the effects saw palmetto has on the scalp. Studies show that these compounds have anti-inflammatory effects, antioxidant effects, improve blood circulation and some have been researched as successful DHT blockers.
Flavonoids in Saw Palmetto
Saw palmetto contains various flavonoids such as: rutin, isoquercitrin, kaempferol 3-O-glucoside, apigenin 7-O-rhamnoglucoside and anthranilic acid. Some of these flavonoids can have significant benefits for hair and skin. For example, rutin is used as an anti-inflammatory drug in patients with osteoarthritis and it has been shown to improve blood circulation and can be used as an anti-thrombotic and anticoagulant;(Choi et al.,2015) this may help improve circulation in the scalp and nourish the hair follicle.
There’s even a direct link between rutin and hair follicle health. A study (Carelli et al., 2012) on the hair follicle regression focused on the activation of apoptosis (cell death) in the hair follicle cells. The researchers used a combination of rutin, spermidine and zeaxanthin on hair cells and noticed that the cells treated with this combination preserved their anti-apoptotic molecules, concluding that these agents might be an effective treatment for hair bulb regression.
Another flavonoid contained by saw palmetto that may be beneficial to your hair’s health is Kaemferol, which has been considered a powerful anti-inflammatory compound and antioxidant. (Chen and Chen 2013) Furthermore, Kaemferol can be used to improve blood circulation and remove blood stasis (Yu et al., 2013), which may account for Saw Palmetto’s potential effects on promoting hair growth.
Apigenin, another flavonoid in Saw Palmetto is also known as a good anti-inflammatory and antioxidant agent (Karamese et al., 2016), so both these flavonoids may help with the treatment of folliculitis and reducing inflammation of the scalp.
Phytosterols in Saw Palmetto
The beta sitosterol in saw palmetto is similar to cholesterol in its chemical structure and may be one of the ingredients in the plant that help most in the treatment of hair loss. It is used as a prevention method and in the management of a multitude of illnesses, from cancer to allergies.
Saw Palmetto is a DHT Blocker
A study in 2002 used 5-alpha reductase inhibitors such as liposterolic extract from saw palmetto and beta-sitosterol to see whether they work in the treatment of Androgenetic alopecia. The results of the study showed a great response to the treatment as 60% of the patients showed improvements. The authors believe that the beta-sitosterols and the liposterolic extract from the saw palmetto may work in the treatment of androgenetic alopecia as a DHT blocker via the enzyme 5-alpha reductase.(Prager et al.,2002)
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Another study hypothesized that targeting 5AR as well as inflammatory pathways may have positive effects in AGA and benign prostatic hyperplasia, both being treated with 5-alpha reductase inhibitors such as finasteride. After testing hair follicle dermal papilla cells and prostate cells in vitro by exposing them to stigmasterol and beta sitosterol the authors concluded that the naturally derived 5-alpha reductase inhibitors represent a good approach in the treatment of androgenetic alopecia and benign prostatic hyperplasia. (Chen et al.,2016)
There’s another study that confirms the results of using stigmasterol and beta sitosterol isolated from plants as anti-inflammatory compounds (Gomez et al.,1999). The study was performed on rats with induced ear edema by using a topical solution and measuring the effect it had on their skin. The inflammation was reduced depending on the amount used in the ear with authors concluding that beta sitosterols and stimasterols are good anti-inflammatory agents when applied topically in acute inflammation.
Saw Palmetto’s Fatty Acids
It has been hypothesized that the fatty acids in saw palmetto may also contribute in inhibiting 5-alpha reductase and studies have shown their efficacy in benign prostatic hyperplasia (Horacio et al.,2011), which may suggest their effect as DHT blockers. Saw Palmetto’s fatty acids that may have effects on the scalp are lauric acid and oleic acid.
A study in 2009(Abe et al.) concluded that the major constituents of Saw Palmetto Extract, lauric acid, oleic acid, mysritic acid and linoleic acid inhibit 5AR activity. These fatty acids may contribute to inhibiting DHT in the scalp when using topical saw palmetto extract or liposterolic supplements and may account for the similar effects saw palmetto has with finasteride.
Saw Palmetto seems like a promising treatment with few to no side effects. It is already available and can be used by anyone as a liposterolic extract in capsules, a liquid extract or can be consumed as tea. However, those who want to get the benefits of the plant’s fatty acids should know that they are not soluble in water and by consuming it as tea they might miss on some of its beneficial effects.
What is 5-alpha reductase?
5-alpha reductase is an enzyme that’s responsible for catalyzing the conversion of the male sex hormone testosterone into DHT by adding a double bond to the hormones’s structure. This enzymatic conversion is essential for various biological processes.
DHT is a more potent androgen (male hormone) than testosterone and is primarily responsible for the development and maintenance of male characteristics, particularly during puberty. It plays a vital role in the development of male sex organs, body hair growth, and the deepening of the voice.
However, 5-alpha reductase and DHT are not exclusive to males; they also exist in females but at lower levels. In males, DHT is involved in hair growth on the face, body, and scalp, but it can also contribute to male pattern baldness (androgenetic alopecia).
References and further reading
- Marks, Leonard S et al. Tissue effects of saw palmetto and finasteride: use of biopsy cores for in situ quantification of prostatic androgens, Urology , Volume 57 , Issue 5 , 999 – 1005 https://www.ncbi.nlm.nih.gov/pubmed/11337315
- Rossi A, Mari E, Scarno M, Garelli V, Maxia C, Scali E, Iorio A, Carlesimo M. Comparitive effectiveness of finasteride vs Serenoa repens in male androgenetic alopecia: a two-year study. Int J Immunopathol Pharmacol. 2012 Oct-Dec;25(4):1167-73. https://www.ncbi.nlm.nih.gov/pubmed/23298508
- Jun-Hui Choi, Dae-Won Kim, Se-Eun Park, Hyo-Jeong Lee, Ki-Man Kim, Kyung-Je Kim, Myung-Kon Kim, Sung-Jun Kim, Seung Kim, Anti-thrombotic effect of rutin isolated from Dendropanax morbifera Leveille, Journal of Bioscience and Bioengineering, Volume 120, Issue 2, August 2015, Pages 181-186, ISSN 1389-1723, http://dx.doi.org/10.1016/j.jbiosc.2014.12.012. (http://www.sciencedirect.com/science/article/pii/S1389172314004915)
- h Carelli, S., Hebda, D. M., Traversa, M. V., Messaggio, F., Giuliani, G., Marzani, B., Benedusi, A., Di Giulio, A. M. and Gorio, A. (2012), A specific combination of zeaxanthin, spermidine and rutin prevents apoptosis in human dermal papilla cells. Exp Dermatol, 21: 953–955. doi:10.1111/exd.12029 https://www.ncbi.nlm.nih.gov/pubmed/23088714
- Chen, A. Y., & Chen, Y. C. (2013). A review of the dietary flavonoid, kaempferol on human health and cancer chemoprevention. Food Chemistry, 138(4), 2099–2107. http://doi.org/10.1016/j.foodchem.2012.11.139 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3601579/
- Victoria García-Mediavilla, Irene Crespo, Pilar S. Collado, Alejandro Esteller, Sonia Sánchez-Campos, María J. Tuñón, Javier González-Gallego, The anti-inflammatory flavones quercetin and kaempferol cause inhibition of inducible nitric oxide synthase, cyclooxygenase-2 and reactive C-protein, and down-regulation of the nuclear factor kappaB pathway in Chang Liver cells, European Journal of Pharmacology, Volume 557, Issues 2–3, 28 February 2007, Pages 221-229, ISSN 0014-2999, http://dx.doi.org/10.1016/j.ejphar.2006.11.014.(http://www.sciencedirect.com/science/article/pii/S0014299906012659)
- Murat Karamese, Huseyin Serkan Erol, Mevlut Albayrak, Gulname Findik Guvendi, Emsal Aydin, and Selina Aksak Karamese Anti-oxidant and anti-inflammatory effects of apigenin in a rat model of sepsis: an immunological, biochemical, and histopathological study Immunopharmacology And Immunotoxicology Vol. 38 , Iss. 3,2016 https://www.ncbi.nlm.nih.gov/pubmed/27144896
- 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. Erratum in: J Altern Complement Med. 2006 Mar;12(2):199. https://www.ncbi.nlm.nih.gov/pubmed/12006122
- Chen, L., Wang, J., Mouser, G., Li, Y. C., and Marcovici, G. (2016) Blockade of Androgen Markers Using a Novel Betasitosterol, Thioctic Acid and Carnitine-containing Compound in Prostate and Hair Follicle Cell-based Assays. Phytother. Res., 30: 1016–1020. doi: 10.1002/ptr.5611. https://www.ncbi.nlm.nih.gov/pubmed/26990224
- Gómez MA, Sáenz MT, García MD, Fernández MA., Study of the topical anti-inflammatory activity of Achillea ageratum on chronic and acute inflammation models. Z Naturforsch C. 1999 Nov;54(11):937-41.https://www.ncbi.nlm.nih.gov/pubmed/10627992
- Priestap, H.A., Quirke, J.M.E., Houle, P. et al. Chem Nat Compd (2011) 47: 511. doi:10.1007/s10600-011-9983-4 http://link.springer.com/article/10.1007/s10600-011-9983-4
- Masayuki Abe, Yoshihiko Ito, Luvsandorj Oyunzul, Tomomi Oki-Fujino, , Shizuo Yamada, Pharmacologically Relevant Receptor Binding Characteristics and 5α-Reductase Inhibitory Activity of Free Fatty Acids Contained in Saw Palmetto Extract – Department of Pharmacokinetics and Pharmacodynamics and Global Center of Excellence (COE) Program, School of Pharmaceutical Sciences, University of Shizuoka https://www.ncbi.nlm.nih.gov/pubmed/19336899/