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Burdock Root For Hair Loss? A Look Into The Evidence

First Published Jan 13 2025
Last Updated Jan 13 2025
Ingredients
Natural Remedies
Researched & Written By:
Ben Fletcher, PhD
Reviewed By:
Rob English, Medical Editor
Burdock Root For Hair Loss? A Look Into The Evidence

Article Summary

Burdock root, derived from the plant Arctium lappa, has long been used in traditional medicine for its purported anti-inflammatory, antimicrobial, and antioxidant properties. In recent years, it has been included in natural hair loss treatments, with claims that it promotes hair growth. Some studies have explored compounds within burdock root, such as arctiin and chlorogenic acid, showing protective effects on hair follicle cells in laboratory settings. However, no clinical trials directly support the use of burdock root for treating hair loss in humans. Current evidence is limited to in vitro studies and small-scale trials on other uses, making it difficult to draw firm conclusions about its effectiveness for hair growth. Additionally, there are no established safety guidelines for its use on hair, and more research is needed to confirm whether it can have any meaningful impact on hair regrowth.

Full Article

Arctium lappa, commonly known as burdock, is a type of plant that can now be found growing around the world. Different parts of the burdock plant have seen use in traditional medicine, particularly the root, and it is claimed to have anti-inflammatory and anti-cancer properties, amongst many others.[1]Yosri, N., Alsharif, S.M., Xiao, J., Musharraf, S.G., Zhao, C., Saeed, A., Gao, R., Said, N.S., Di Minno, A., Daglia, M. and Guo, Z. (2023). Arctium lappa (Burdock): Insights from ethnopharmacology … Continue reading Some studies have investigated the ingredients found within burdock root, revealing positive effects on human hair follicle cells grown in a dish.

In this article, we’ll examine what burdock root really is, some of its functions, and whether or not it can affect the hair follicle. We will also find any clinical evidence that supports the use of burdock root in treating hair loss and, finally, establish if it is safe to use. 

Key Takeaways

  • What is it? Burdock is a biennial plant native to Europe and Asia, now found growing around the world. Although evidence surrounding burdock root itself is lacking regarding hair and the hair follicle, some studies have investigated key active ingredients found within the root. Arctiin has been shown to exhibit protective effects in human hair follicle dermal papilla cells (HHDPCs) treated with reactive oxygen species (ROS), with arctiin pretreatment protecting the cells from death and reducing ROS production. Similar effects were observed when pretreating HHDPCs with chlorogenic acid, suggesting that both compounds might possess functions beneficial to hair loss. A clinical study also investigated the use of a capsule containing β-sitosterol in treating androgenic alopecia (AGA), with the authors reporting increased hair density by the end of the study. However, each of these studies presents caveats, all of which we critically examine in this article.
  • Clinical Data. Despite the wealth of clinical studies involving burdock root, none appear to have assessed its efficacy in treating hair loss or promoting hair growth.
  • Evidence Quality. 5/100 by our metrics
  • Safety. There is currently no safety data regarding the consumption or application of burdock root.
  • Best Practices. Given the lack of clinical data, there are no current best practices to note.

What is Burdock?

Burdock is a type of biennial plant that is native to Europe and Asia, but due to its ability to grow in a variety of environments, it can now be found around the world.[2]de Souza, A. R. C., de Oliveira, T. L., Fontana, P. D., Carneiro, M. C., Corazza, M. L., de Messias Reason, I. J., & Bavia, L. (2022). Phytochemicals and biological activities of burdock (Arctium … Continue reading Burdock has seen use for thousands of years for both nutritional and medicinal reasons, and it is the root of the plant which is generally utilized the most.[3]Chan, Y.S., Cheng, L.N., Wu, J.H., Chan, E., Kwan, Y.W., Lee, S.M.Y., Leung, G.P.H., Yu, P.H.F. and Chan, S.W. (2011). A review of the pharmacological effects of Arctium lappa … Continue reading Indeed, the therapeutic applications of burdock root are wide-ranging, having been used in traditional medicine to treat everything from skin diseases to tuberculosis.[4]Yosri, N., Alsharif, S.M., Xiao, J., Musharraf, S.G., Zhao, C., Saeed, A., Gao, R., Said, N.S., Di Minno, A., Daglia, M. and Guo, Z. (2023). Arctium lappa (Burdock): Insights from ethnopharmacology … Continue reading

How Does Burdock Root Work?

Research into burdock root is extensive, which is perhaps unsurprising given its reputation in traditional medicine. Burdock root contains active ingredients such as phenolic acids, flavonoids, tannins, and phytosterols, amongst others. [5]Yosri, N., Alsharif, S.M., Xiao, J., Musharraf, S.G., Zhao, C., Saeed, A., Gao, R., Said, N.S., Di Minno, A., Daglia, M. and Guo, Z. (2023). Arctium lappa (Burdock): Insights from ethnopharmacology … Continue reading This variety of compounds likely contributes to the wide range of biological activity exhibited by burdock root.

Before we jump into those studies, it is important to note that burdock root can be prepared and applied in a great many ways. From brewing a tea with the whole root through to alcohol-based extractions, the effects of burdock root may be influenced by how it is prepared. This means that the potential benefits of a burdock root tea may not be exhibited by a burdock root extract, and vice versa. Furthermore, many of the studies discussed here were performed outside of the human body, so the benefits may not apply to humans.

We will start by summarizing the most prominent beneficial effects of burdock root, some of which are not directly related to the hair, before taking a more in-depth look at how this ingredient may benefit hair loss.

Anti-tumor activity
One of the foremost areas of research into burdock root comes in relation to its anti-cancer and anti-tumor activity. It has been shown that treatment of various cancer cell lines in vitro (outside of a living organism, in a dish) with different burdock root extracts caused the cells to lose viability (Figure 1); in other words, burdock root extract caused the cancer cells to die.[6]Don, R. A. S. G., & Yap, M. K. K. (2019). Arctium lappa L. root extract induces cell death via mitochondrial-mediated caspase-dependent apoptosis in Jurkat human leukemic T cells. Biomedicine … Continue reading

Figure 1: Cell viability of cancerous cell lines HeLa (A), MCF-7 (B), Jurkat T cells (C), and normal cell line 3T3 (D). Cells were treated for 24 hours with increasing concentrations of ethanol (EtOH), hexane (Hex), and ethyl acetate (EA) extracts of burdock root. Cell viability indicates the proportion of healthy, living cells.[7]Don, R. A. S. G., & Yap, M. K. K. (2019). Arctium lappa L. root extract induces cell death via mitochondrial-mediated caspase-dependent apoptosis in Jurkat human leukemic T cells. Biomedicine … Continue reading

A separate study investigated the anti-tumor effects of burdock root on tumors in mice.[8]Zhang, M., Wang, Y. W., Zhu, Y. Z., & Gu, X. L. (2021). Discovery of quality control ingredients in burdock root by combining anti‐tumor effects and UHPLC–QqQ–MS/MS. Biomedical … Continue reading Tumor-bearing mice were treated orally with or without burdock root [2.25g per kg of body weight] for 15 days. One group of mice was also treated with fluorouracil, a chemotherapy drug that would act as a positive control (something that should exhibit the desired effect). Unsurprisingly, fluorouracil caused the greatest reduction in tumor volume and weight; however, eight of the ten burdock root-treated groups (S1-10) also had reduced tumor weight compared to the untreated mice (Figure 2).

Figure 2: Tumor weight in mice after 15 days of treatment with the negative control (ctrl), fluorouracil (positive), or burdock root (S1-10).[9]Zhang, M., Wang, Y. W., Zhu, Y. Z., & Gu, X. L. (2021). Discovery of quality control ingredients in burdock root by combining anti‐tumor effects and UHPLC–QqQ–MS/MS. Biomedical … Continue reading

It is believed that much of the anti-tumor activity may be elicited by arctigenin and/or arctiin, two of the key active compounds found within burdock root, and a significant amount of research continues to investigate their beneficial effects.[10]de Souza, A. R. C., de Oliveira, T. L., Fontana, P. D., Carneiro, M. C., Corazza, M. L., de Messias Reason, I. J., & Bavia, L. (2022). Phytochemicals and biological activities of burdock (Arctium … Continue reading

Anti-inflammatory activity

Several animal-based studies have shown the anti-inflammatory potential of burdock root. One such study was conducted on rats that had inflammation induced in their paws.[11]Conea, S., Mogosan, C., Vostinaru, O., Toma, C.C., HEPCAL, I.C., Cazacu, I., Cristina, P.O.P. and Vlase, L. (2017). Polyphenolic profile, anti-inflammatory and antinociceptive activity of an extract … Continue reading

They found that inflammation was significantly inhibited in the rats that had been orally administered burdock root extract before the test when compared to the control group. Similar results had previously been reported by another study, which found that subcutaneous administration (injection into the fat under the skin) of burdock root extract significantly decreased inflammation levels in the rats’ paws.[12]Lin, C. C., Lin, J. M., Yang, J. J., Chuang, S. C., & Ujiie, T. (1996). Anti-inflammatory and radical scavenge effects of Arctium lappa. The American journal of Chinese medicine, 24(02), 127-137. … Continue reading

It has also been shown that burdock root extract can inhibit allergy-induced inflammation in mice.[13]Knipping, K., van Esch, E. C., Wijering, S. C., van der Heide, S., Dubois, A. E., & Garssen, J. (2008). In Vitro and in vivo anti-allergic effects of Arctium lappa L. Experimental biology and … Continue reading Mice received topical or oral burdock root extract before receiving an allergic challenge, and they found that although the oral burdock root had no effect, the topical burdock root reduced swelling by 50%. The same study also revealed that burdock root significantly reduced the release of inflammatory cytokines from human white blood cells in vitro, which potentially offers some insight into how burdock root mediates its anti-inflammatory effects.

Antimicrobial activity

A number of studies have also highlighted the antimicrobial activity of burdock root, whether antibacterial or antifungal.

As an antibacterial, burdock root inhibits the formation of biofilms, the communities of bacteria that form, which increase their resistance against the immune system.[14]Rajasekharan, S. K., Ramesh, S., Bakkiyaraj, D., Elangomathavan, R., & Kamalanathan, C. (2015). Burdock root extracts limit quorum-sensing-controlled phenotypes and biofilm architecture in major … Continue reading

In vitro application of burdock root significantly reduced the thickness and surface area of biofilms produced by E. coli, P. mirabilis, and S. marcescens, three bacterial species that are commonly associated with urinary tract infections (Figure 3).

Figure 3: Antibiofilm activity of burdock root extract against bacteria found in the urinary tract.[15]Rajasekharan, S. K., Ramesh, S., Bakkiyaraj, D., Elangomathavan, R., & Kamalanathan, C. (2015). Burdock root extracts limit quorum-sensing-controlled phenotypes and biofilm architecture in major … Continue reading

A separate study described the antifungal effects of burdock root. They grew two common types of fungus – A. niger and P. hirsutum – in a dish which also contained burdock root extract.[16]Fierascu, R.C., Georgiev, M.I., Fierascu, I., Ungureanu, C., Avramescu, S.M., Ortan, A., Georgescu, M.I., Sutan, A.N., Zanfirescu, A., Dinu-Pirvu, C.E. and Velescu, B.S. (2018). Mitodepressive, … Continue reading After 6 days, they observed a significantly larger inhibition zone in the burdock root plate vs the negative control; in other words, reduced fungal growth in the plate containing burdock root (Figure 4).

Figure 4: Inhibition zone diameters of the controls, V. persica, and A. lappa (burdock) against the tested fungal species. The different letters above the bars represent statistical significance. If a letter is different between groups, then it indicates a significant difference (p<0.05). If the letter is the same then the groups are not statistically different. Comparisons were only performed within each group; no comparisons were performed between A. niger and P. hirsutum. For example: in the A. niger group, the inhibition zone in the A. lappa test was significantly larger than the negative control, but not significantly larger than V. persica.[17]Fierascu, R.C., Georgiev, M.I., Fierascu, I., Ungureanu, C., Avramescu, S.M., Ortan, A., Georgescu, M.I., Sutan, A.N., Zanfirescu, A., Dinu-Pirvu, C.E. and Velescu, B.S. (2018). Mitodepressive, … Continue reading

Some of the compounds within burdock root have also been shown to exhibit antiviral activity. Arctigenin has been shown in vitro and in vivo to exert activity against human immunodeficiency virus type-1, while caffeic acid and chlorogenic acid exhibit antiviral effects against both herpesvirus and adenovirus.[18]Chan, Y.S., Cheng, L.N., Wu, J.H., Chan, E., Kwan, Y.W., Lee, S.M.Y., Leung, G.P.H., Yu, P.H.F. and Chan, S.W. (2011). A review of the pharmacological effects of Arctium lappa (burdock). … Continue reading

Antioxidant Activity

Antioxidants are compounds that neutralize free radicals, a collection of molecules that cause damage via oxidative stress, and are believed to play a role in a range of human health issues.

One study conducted a test of orally administered burdock root in protecting rats from lead acetate (Pb(II)) induced liver injury.[19]Alhusaini, A., Fadda, L., Hasan, I.H., Ali, H.M., El Orabi, N.F., Badr, A.M., Zakaria, E., Alenazi, A.M. and Mahmoud, A.M. (2019). Arctium lappa root extract prevents lead-induced liver injury by … Continue reading Rats received lead and burdock root extract [200mg per kg] or vitamin C for 7 days. After the 7 days, the rats which had received burdock root or vitamin C had significantly reduced levels of malondialdehyde (MDA; marker of oxidative stress) and nitric oxide (NO; free radical), as well as increased levels of glutathione (GSH; major antioxidant) and superoxide dismutase (SOD; key antioxidant component), indicating that burdock root protected the rats against oxidative damage to the liver (Figure 5).

Figure 5: The effects of ALRE (A. lappa root extract) and vitamin C on markers of oxidative stress in the liver of rats treated with lead acetate (Pb(II)). First column = negative control; second column = rats treated with lead; third column = rats treated with lead and burdock root extract; fourth column = rats treated with lead and vitamin C. Burdock root protected against the lead-induced increase of malondialdehyde (MDA) and nitric oxide (NO) as well as the decrease in glutathione (GSH) and superoxide dismutase (SOD).[20]Alhusaini, A., Fadda, L., Hasan, I.H., Ali, H.M., El Orabi, N.F., Badr, A.M., Zakaria, E., Alenazi, A.M. and Mahmoud, A.M. (2019). Arctium lappa root extract prevents lead-induced liver injury by … Continue reading

Burdock root has also been shown to exhibit antioxidant properties in humans. 36 patients (10 men, 26 women) aged between 50 and 70 years, all with osteoarthritis of their knee, were studied for 42 days.[21]Maghsoumi‐Norouzabad, L., Alipoor, B., Abed, R., Eftekhar Sadat, B., Mesgari‐Abbasi, M., & Asghari Jafarabadi, M. (2016). Effects of Arctium lappa L.(Burdock) root tea on inflammatory status … Continue reading They took acetaminophen and glucosamine every day and, alongside this, three cups of burdock root tea or boiled water. At the end of the 42 days, patients who received burdock root tea had significantly reduced MDA levels in their blood compared to baseline and control patients. They also had significantly increased SOD levels vs baseline and significantly increased total antioxidant capacity vs baseline and the control group.

So, the evidence shows that burdock root can exhibit anti-tumor, anti-inflammatory, antimicrobial, and antioxidant effects. As stated, it was not possible to discuss all of the studies here, but there are several published reviews that explore these and other effects in greater detail.[22]de Souza, A. R. C., de Oliveira, T. L., Fontana, P. D., Carneiro, M. C., Corazza, M. L., de Messias Reason, I. J., & Bavia, L. (2022). Phytochemicals and biological activities of burdock (Arctium … Continue reading,[23]Chan, Y.S., Cheng, L.N., Wu, J.H., Chan, E., Kwan, Y.W., Lee, S.M.Y., Leung, G.P.H., Yu, P.H.F. and Chan, S.W. (2011). A review of the pharmacological effects of Arctium lappa (burdock). … Continue reading,[24]Yosri, N., Alsharif, S.M., Xiao, J., Musharraf, S.G., Zhao, C., Saeed, A., Gao, R., Said, N.S., Di Minno, A., Daglia, M. and Guo, Z. (2023). Arctium lappa (Burdock): Insights from ethnopharmacology … Continue reading

None of these studies were completed on the hair follicle; however, they do not offer us direct insight into the effects that burdock root may have on hair growth. So, let’s take a look at some studies that do offer insight into the effects of burdock root on the hair follicle.

How Can Burdock Root Have an Impact on Hair Follicles?

Unfortunately, no studies have investigated the effects of burdock root on hair loss, whether as a tea, an extract, or anything in between. However, as burdock root contains so many active ingredients, some of these have been studied in relation to hair growth and hair loss.

Given the absence of burdock root studies, we will explore the effects of some of these isolated ingredients below. However, it is important to note that ingredients may behave differently when isolated compared to how they behave when they are part of the whole burdock root.

Arctiin

Arctiin, one of the key active ingredients found within burdock root, is a lignan that has seen wide usage in traditional medicine. A large number of studies have investigated arctiin for potential therapeutic applications, identifying beneficial effects such as working as an anti-inflammatory, inhibiting the growth of pathogens, exhibiting neuroprotection, and more.[25]Gao, Q., Yang, M., & Zuo, Z. (2018). Overview of the anti-inflammatory effects, pharmacokinetic properties and clinical efficacies of arctigenin and arctiin from Arctium lappa L. Acta … Continue reading

Interestingly, one study also investigated the effects of arctiin in human hair follicle dermal papilla cells (HHDPCs), a key type of cell for hair growth which is found in the bulb of the hair follicle.[26]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading The study was based on the hypothesis that a group of molecules called reactive oxygen species (ROS) are key causative factors in hair loss, a hypothesis that is gaining increasing support.

ROS are highly reactive molecules that come from oxygen. They elicit their effects by transferring electrons with another molecule, which causes changes to both molecules.[27]Sies, H., Belousov, V.V., Chandel, N.S., Davies, M.J., Jones, D.P., Mann, G.E., Murphy, M.P., Yamamoto, M. and Winterbourn, C. (2022). Defining roles of specific reactive oxygen species (ROS) in cell … Continue reading ROS are largely produced internally, such as hydrogen peroxide (H2O2) produced by melanin production in the hair follicle, but there are also external sources.[28]Denat, L., Kadekaro, A. L., Marrot, L., Leachman, S. A., & Abdel-Malek, Z. A. (2014). Melanocytes as instigators and victims of oxidative stress. Journal of Investigative Dermatology, 134(6), … Continue reading

Although ROS are crucial to various biological processes, including cell signaling, they can cause damage to the body when their levels become too high. This occurs through a process called oxidative stress, and studies have linked increased levels of ROS to balding and different types of alopecia.[29]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

As such, the present study sought to investigate the protective effects of arctiin against H2O2-induced damage to HHDPCs. Firstly, the authors treated HHDPCs in vitro with increasing concentrations of arctiin to see if it had any effect on the cells without any other stimuli (Figure 6A). They noted that arctiin at 10uM, 20uM, and 30uM significantly increased cell viability (there were a greater number of healthy cells); however, as no statistical analysis appears to have been performed, it is not possible to draw conclusions from this.[30]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

Figure 6: Arctiin treatment of HHDPCs. (A) Cell viability in HHDPCs treated with increasing concentrations of arctiin for 24hrs. (B) Cell viability in HHDPCs treated with or without H2O2 and arctiin.[31]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

They then moved on to H2O2 treatment of the cells, which acts as a model of ROS-induced damage. Here, some cells were treated with arctiin for 8 hours before being treated with H2O2. In the cells treated with 20uM or 30uM of arctiin, they observed a statistically significant increase in cell viability vs the H2O2-only cells, indicating that arctiin was able to attenuate the cell death caused by H2O2 (Figure 6B).[32]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

It was found that pretreatment with arctiin influenced the cell cycle of the HHDPCs. Treatment with H2O2 caused an accumulation of cells in the sub-G1 phase (Figure 7B), which is indicative of cell death, and an accumulation of G2 phase cells (Figure 7C), which is indicative of cell cycle arrest (the cycle stops, preventing the cell from dividing and impairing the growth of the cell population). However, by pretreating the cells with 20uM of arctiin for 8 hours, these detrimental effects were prevented.[33]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

Figure 7: Effects of H2O2 and arctiin on the HHDPC cell cycle. (A) The proportion of HHDPC cells in each stage of the cell cycle. (B) The percentage of cells in the sub-G1 phase, which would indicate cell death. (C) The ratio of cells in the G1 phase to cells in the G2 phase, with a lower ratio indicating increased cell cycle arrest (in other words, cells that are not growing). [34]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

The authors then assessed the effects of arctiin on ROS accumulation in the cells. Treatment of the HHDPCs with H2O2 caused a statistically significant increase (45.77%) in ROS production within the cells (Figure 8). Once again, however, pretreatment of the cells with 20uM of arctiin largely diminished this detrimental effect (29.77%).[35]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

Figure 8: Pretreatment of HHDPCs with arctiin [20uM] significantly reduces the H2O2-mediated increase in ROS production. A reduction in the number of M phase cells is indicative of reduced ROS production.[36]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

Finally, the authors investigated the effects of arctiin on senescence. Cellular senescence is essentially cell cycle arrest, a state that we explored earlier in this section. In this state, the cell no longer progresses through the cell cycle and divides – growth is stopped. Cellular senescence is linked to a number of health issues, including cancer, and studies have shown increased levels of senescence in cells of the balding scalp.[37]Bahta, A. W., Farjo, N., Farjo, B., & Philpott, M. P. (2008). Premature senescence of balding dermal papilla cells in vitro is associated with p16INK4a expression. Journal of Investigative … Continue reading

The researchers observed a statistically significant increase in the proportion of senescent cells when treating HHDPCs with H2O2 (Figure 9). Although this was not completely alleviated by arctiin pretreatment, application of arctiin did lead to a significant reduction in the proportion of senescent cells.[38]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

Figure 9: Pretreatment of HHDPCs with Arctiin reduces the H2O2-mediated increase in cellular senescence.[39]Bae, S., Lim, K.M., Cha, J.H., An, I.S., Lee, J.P., Lee, K.S., Lee, G.T., Lee, K.K., Jung, H.J., Ahn, K.J., An, S. (2014), Arctiin blocks hydrogen peroxide-induced senescence and cell death through … Continue reading

So, this study not only adds support to the theory that ROS may induce hair loss, but it also reveals that arctiin might be able to reduce or alleviate some of these detrimental effects. However, there are a couple of important caveats.

Firstly, the entire study was conducted on cells in vitro. While this is generally the first step when starting a new investigation, it is not directly relevant to humans as a whole. How HHDPCs, H2O2, and arctiin all interact in vitro is not necessarily indicative of how they interact within the body, so the results cannot be used to draw definitive conclusions on potential therapeutic applications of arctiin.

Moreover, the authors declared that they treated cells with dimethyl sulfoxide (DMSO) whenever they were not using arctiin (in their control groups). Studies have shown that DMSO can affect cells in a number of ways, including by reducing ROS accumulation due to DMSO acting as a scavenger of ROS.[40]Verheijen, M., Lienhard, M., Schrooders, Y., Clayton, O., Nudischer, R., Boerno, S., Timmermann, B., Selevsek, N., Schlapbach, R., Gmuender, H. and Gotta, S. (2019). DMSO induces drastic changes in … Continue reading Unfortunately, it is unclear if the authors properly controlled for the potential effects of DMSO, so we cannot be sure it did not influence the results.

β-sitosterol

β-sitosterol is a naturally occurring compound found within plants. It is a phytosterol, which is a type of compound that is similar to cholesterol. Numerous studies have investigated β-sitosterol, identifying potentially beneficial effects such as protection for the liver, aiding in wound healing, and working as an antioxidant, amongst many others.[41]Babu, S., & Jayaraman, S. (2020). An update on β-sitosterol: A potential herbal nutraceutical for diabetic management. Biomedicine & Pharmacotherapy, 131, 110702. Available at: … Continue reading
An in silico (computer simulation) study suggested that β-sitosterol may be a potent inhibitor of 5α-reductase type I (5AR1).[42]Zamani, P., Mokhtari, O., & Dehghanian, F. (2021). Identification of beta-sitosterol and stigmasterol as possible inhibitors of 5 alpha-reductase 1: an in-silico study. Precision Medicine and … Continue reading

Expressed in the sebaceous glands of the hair follicle, the primary function of 5AR1 is to convert testosterone into dihydrotestosterone (DHT). Indeed, the 5α-reductase inhibitor dutasteride is prescribed off-label to treat AGA, as it targets both 5AR1 and 5α-reductase type II (which is also linked to hair loss). In a highly interesting finding, the in silico study predicted that β-sitosterol may have a stronger binding affinity to 5AR1 than dutasteride, presenting the possibility that it might function as a natural inhibitor of 5AR1 (and, therefore, be useful for treating AGA).

Fortunately, one clinical study has investigated the effects of β-sitosterol of AGA.[43]Prager, N., Bickett, K., French, N., & Marcovici, G. (2002). A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of … Continue reading

This randomized, double-blinded, placebo-controlled study recruited 26 males with AGA, aged between 23 and 64 years. Twice a day for 21 weeks, the subjects consumed a capsule containing β-sitosterol [50mg] and saw palmetto extract [200mg] or a placebo. Subjects were assessed at baseline (the start of the study) and endline (the end of the study) by staff members, who then visually graded each participant’s hair on a scale of -3 (greatly decreased hair density) to 3 (greatly increased hair density). Self-assessment questions were also provided to each subject, which asked for their opinion on the following: size of bald spot, appearance of hair, growth of hair, rate of hair loss, and satisfaction with appearance of hair.

It should be noted that 7 subjects did not complete the study, 2 of whom cited perceived adverse events as their reason for leaving. In total, 8 adverse events were self-reported by 7 patients, with 4 of those events being reported in the test group (Table 1).[44]Prager, N., Bickett, K., French, N., & Marcovici, G. (2002). A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of … Continue reading

Table 1: Adverse events reported during the study.[45]Prager, N., Bickett, K., French, N., & Marcovici, G. (2002). A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of … Continue reading

At the end of the study, the staff determined that 60% of patients in the treatment group had improvements in their hair density, compared to just 11% of the placebo group (Figure 10).[46]Prager, N., Bickett, K., French, N., & Marcovici, G. (2002). A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of … Continue reading

Figure 10: Staff assessment of improvements in hair density. The percentage of patients determined to exhibit improved density is reported.[47]Prager, N., Bickett, K., French, N., & Marcovici, G. (2002). A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of … Continue reading

Furthermore, via self-assessment, nobody in the treatment group reported deterioration of their bald spot, compared to 33% of the placebo group (Figure 11).[48]Prager, N., Bickett, K., French, N., & Marcovici, G. (2002). A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of … Continue reading

Figure 11: Percentage of patients who reported deterioration of their bald spot during the study, via the self-assessment. [49]Prager, N., Bickett, K., French, N., & Marcovici, G. (2002). A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of … Continue reading

Unfortunately, the results of this study are not conclusive. First and foremost, the treatment group received both β-sitosterol and saw palmetto extract. Moreover, the authors report that the capsule also contained lecithin [50mg], inositol [100mg], phosphatidylcholine [25mg], niacin [15mg], and biotin [100ug] to improve the bioavailability of the β-sitosterol and saw palmetto extract.[50]Prager, N., Bickett, K., French, N., & Marcovici, G. (2002). A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of … Continue reading This creates a very difficult situation whereby it is not at all possible to determine which effects were mediated by β-sitosterol alone, if any.

Furthermore, the methods and results are not robust. Subjective assessments of hair growth/loss (such as visual inspection) are not reliable, with objective methods (such as the use of a trichogram) providing much better analysis. In addition, the authors did not appear to present all the results (what were the outcomes of the other self-assessment questions?), and they did not perform statistical analysis (the authors themselves state that this was not a primary outcome of this small-scale study).

Collectively, this study does not offer useful insight into the effects of β-sitosterol on hair loss.

Chlorogenic Acid

Chlorogenic acid is a polyphenol found abundantly in different plants, fruits, and vegetables. Exhibiting a wide range of effects, numerous studies have explored the therapeutic applications of chlorogenic acid, revealing potential benefits in the treatment of neurodegenerative and cardiovascular diseases, amongst others.[51]Nguyen, V., Taine, E. G., Meng, D., Cui, T., & Tan, W. (2024). Chlorogenic Acid: A Systematic Review on the Biological Functions, Mechanistic Actions, and Therapeutic Potentials. Nutrients, … Continue reading

In a very similar study to that which was discussed in the arctiin section, one research team investigated the protective effects of chlorogenic acid against ROS-induced damage.[52]Benedetto, N., Mangieri, C., De Biasio, F., Carvalho, R. F., Milella, L., & Russo, D. (2024). Malus pumila Mill. cv Annurca apple extract might be therapeutically useful against oxidative stress … Continue reading As before, the authors pretreated HHDPCs with chlorogenic acid (CGA) or procyanidin B2 (PG2), this time for 24hrs, before exposing the cells to H2O2. They showed that pretreatment with chlorogenic acid [1.05 ug per ml] diminished the H2O2-mediated reduction in cell viability (Figure 12) and reduced the H2O2-mediated increase in ROS generation (Figure 13).

Figure 12: Pretreatment of HHDPCs with PB2 or CGA attenuates the H2O2-mediated decrease in cell viability.[53]Benedetto, N., Mangieri, C., De Biasio, F., Carvalho, R. F., Milella, L., & Russo, D. (2024). Malus pumila Mill. cv Annurca apple extract might be therapeutically useful against oxidative stress … Continue reading

Figure 13: Pretreatment of HHDPCs with PG2 or CGA prevented the H2O2-mediated increase in ROS production.[54]Benedetto, N., Mangieri, C., De Biasio, F., Carvalho, R. F., Milella, L., & Russo, D. (2024). Malus pumila Mill. cv Annurca apple extract might be therapeutically useful against oxidative stress … Continue reading

These results are very similar to those presented in the arctiin study we discussed above, so it leads us to a similar conclusion – chlorogenic acid might exhibit effects that are useful in treating hair loss. However, this study also carries with it the caveat of being completed in vitro, meaning that these results are also not indicative of how chlorogenic acid may function in humans.

Can Burdock Root Treat Hair Loss?

Unfortunately, despite the wealth of clinical studies involving burdock root, none have investigated its efficacy in treating hair loss. Therefore, we can’t know for sure what effects it could have on humans with hair loss.

Where Does Burdock Root Rank On The Hierarchy of Evidence?

The hierarchy of evidence is a classification system for the strength of evidence of research. Usually depicted as a pyramid (as below: Figure 14), the lowest quality evidence is shown at the bottom, and the highest quality evidence is shown at the top.[55]Baur, C. (2021). Hierarchy of Evidence, Research Square. Available at: https://www.researchsquare.com/bloog/what-is-the-hierarchy-of-evidence (Accessed: 21 Oct 2024)

Figure 14: Hierarchy of Evidence.[56]Yetley. E.A., MacFarlane, A.J., Greene-Finestone, L.S., Garza, C., Ard, J.D., Atkinson, S.A., Bier, D.M., Carriquiry, A.L., Harlan, W.R., Hattis, D., King, J.C., Krewski, D., O’Connor, D.L., … Continue reading

Given that burdock root is yet to be the subject of randomized control trials, cohort studies, case-control studies, cross-sectional studies, or case studies, the highest level that it can currently be assigned is 2 – mechanistic studies. Low ranks such as this one are given to ingredients that lack robust evidence, which is certainly the case for burdock root. This is not to say that burdock root is ineffective in treating hair loss; rather, it indicates that additional studies must be performed to confirm that burdock root is a suitable treatment for hair loss.

Is Burdock Root Safe?

There are no guidelines relating to safe dosages of burdock root in tea, extract, or other preparations.

One clinical study provided knee osteoarthritis patients (36 males and females between the ages of 50 and 70 years) with 6g of burdock root per day (2g of burdock root in a tea, three times a day): no adverse effects were noted by the authors.[57]Alipoor, B., Norouzabad, L. M., Abed, R., Oskouei, M. A. E., Sadat, B. E., & Jafarabadi, M. A. (2014). Effect of Arctium lappa L.(Burdock) root tea on clinical signs and symptoms in patients with … Continue reading

However, this study was performed on a small scale and should not be used as conclusive evidence of burdock root’s safety. Large-scale clinical studies are required to determine the safe dosages of burdock root for oral consumption and topical application.

Is Burdock Root For Me?

Given that no safety data or relevant clinical evidence exists for burdock root, we do not currently recommend experimenting with it to treat hair loss.

However, those who might want to experiment with burdock root might be:

  • Happy using a product with no data that supports its efficacy in treating hair loss.
  • Happy to experiment with a natural supplement to see if it affects hair growth.

References

References
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Ben Fletcher, PhD

Ben Fletcher, PhD

Benjamin Fletcher is a researcher & writer who holds a BSc in Biological Sciences and an MSc in Genes, Drugs & Stem Cells. Benjamin is currently pursuing a Ph.D. in Molecular Biology & Genetics, conducting research to better understand the regulatory mechanisms that drive muscle atrophy in disease, with a particular focus on the influence of microRNAs.

"... Can’t thank @Rob (PHH) and @sanderson17 enough for allowing me to understand a bit what was going on with me and why all these [things were] happening ... "
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— RDB, 35, New York, U.S.A.
"... There is a lot improvement that I am seeing and my scalp feel alive nowadays... Thanks everyone. "
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— Aayush, 20’s, Boston, MA
"... I can say that my hair volume/thickness is about 30% more than it was when I first started."
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— Douglas, 50’s, Montréal, Canada