Role and Mechanisms of Phytochemicals in Hair Growth and Health

Pharmaceuticals (Basel). 2023 Jan 30;16(2):206. doi: 10.3390/ph16020206.
Role and Mechanisms of Phytochemicals in Hair Growth and Health
Periyanaina Kesika 1 2, Bhagavathi Sundaram Sivamaruthi 2, Subramanian Thangaleela 1, Muruganantham Bharathi 1, Chaiyavat Chaiyasut 1

Hair health is associated with personal distress and psychological well-being. Even though hair loss (alopecia) does not affect humans' biological health, it affects an individual's social well-being. So, treatment for hair problems and improving hair health are obligatory. Several pharmacological and cosmeceutical treatment procedures are available to manage hair loss and promote growth. Several factors associated with hair health include genetics, disease or disorder, drugs, lifestyle, chemical exposure, and unhealthy habits such as smoking, diet, and stress. Synthetic and chemical formulations have side effects, so people are moving towards natural compounds-based remedies for their hair problems. The history of using phytochemicals for hair health has been documented anciently. However, scientific studies on hair loss have accelerated in recent decades. The current review summarizes the type of alopecia, the factor affecting hair health, alopecia treatments, phytochemicals' role in managing hair loss, and the mechanisms of hair growth-stimulating properties of phytochemicals. The literature survey suggested that phytochemicals are potent candidates for developing treatment procedures for different hair problems. Further detailed studies are needed to bring the scientific evidence to market.

Keywords: alopecia; hair growth stimulation; hair health; hair loss; phytochemicals.

As usual, "they" list genetics as a 'cause' in both the short and long-form. There is zero evidence to support this hypothesis whatsoever.

Full: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9963650/

"Role of Phytochemicals in Managing Hair Loss
This section summarizes the representative studies on hair growth-promoting activities of phytochemicals.

The herbal extract was prepared with aqueous extracts of Urtica dioica L. root, Urtica urens L. leaf, Equisetum arvense L. leaf, Achillea millefolium L. aerial part, Matricaria chamomilla L. flower and Ceratonia siliqua L. fruit. The herbal extract mixture (HEM) was rich in vitamins (thiamine, riboflavin, pyridoxine, and ascorbic acid) and flavonoids (myricetin, quercetin, and kaempferol). The treatment of HEM significantly downregulated the expression of IL-1α, one of the important hair loss mediators and growth inhibitory agents, in HaCaT cells compared to the control. The study suggested that HEM could be an adjuvant therapeutic agent for nonscarring alopecia [85].

Cyclic adenosine monophosphate (cAMP), an intracellular messenger, is one of the hair growth-promoting target molecules. Dermal papilla cells (DPCs) are involved in hair morphogenesis and regeneration. The treatment of α-phellandrene supported the proliferation of DPCs and increased the PKA C α (protein kinase A catalytic subunit) and CREB (cAMP-responsive element binding protein). Furthermore, CREB-dependent growth factors, such as VEGF (vascular endothelial growth factor, known for its role in accelerating hair growth) expression, were upregulated in DPCs. The cAMP inhibitors reversed the changes, which showed that α-phellandrene could prevent hair loss via the cAMP-dependent pathway [86].

The ethanolic (EEAS) and aqueous extracts of Albizia saponaria (Lour.) Blume ex Miq. barks (AEAS) were studied for their ability to promote hair growth. The EEAS was rich in tannins, alkaloids, flavonoids, saponins, phenols, and triterpenoids. The treatment of EEAS and AEAS, at a concentration of 5–20%, significantly nourished and promoted hair growth in rabbits [87]. León et al. [88] reported that the aqueous extract of latex of Jatropha gaumeri Greenm. treatment showed wound-healing effects and hair growth stimulation by facilitating the regeneration of hair follicles in male Balb/c mice [88].

The oral and topical application of β-cyclodextrin inclusion complex containing γ-linolenic acid, β-sitosterol, EGCG, and genistein for 270 days showed hair loss preventive effects in androgenetic alopecia male subjects. The baldness in the vertex scalp of subjects was noticed at baseline. After 90 days of treatment, a significant improvement in hair thickening was observed. After 270 days of treatment, there was no evidence of hair loss in the study subjects. The study suggested that a plant-based, nano-complexed formula could be a supportive treatment strategy for androgenetic alopecia and drug-based treatments [89]. Leaves and roots of Arctium lappa L. are used to treat skin inflammation, promote wound healing, act against dandruff, and prevent hair loss [90]."

Interesting stuff. So is there any practical use of this knowledge?

It wouldn't hurt to experiment with a topical since these are all natural ingredients

I've independently researched most of these over the years. They all have some merit.

One could search here within the "Google", not the default "inside" and locate some of the research in the upper left-hand corner.