Ashwagandha and Curcumin in Hair Growth Supplements
The review examines why healthy liver function matters in the context of hair-growth supplements.
William Gaunitz, WTSClinical Trichologist · Expert Reviewer
Inside this review
Use these questions to navigate the complete physician-authored review below.
The review places supplement use in the wider context of liver function and follicular health.
Read this section →Read the author’s discussion of ashwagandha and reported liver-injury concerns.
Read this section →Complete production article and literature cited.
Ashwagandha and Curcumin in Hair Growth Supplements
Introduction
Over the past decade, the hair supplement industry has expanded dramatically, reflecting growing consumer interest in nutritional and botanical approaches to supporting hair growth.
Many modern formulations now extend beyond basic vitamins and minerals to include plant-derived compounds marketed for their ability to reduce stress and regulate inflammation. The most common ingredients are ashwagandha (Withania somnifera) and curcumin, the primary bioactive compound in turmeric.
The appeal is easy to understand: these ingredients sound calming, natural, and even protective. Ashwagandha is positioned as a stress-adaptation herb; curcumin is promoted as an anti-inflammatory compound. For patients already worried about shedding, inflammation, hormones, or stress, they can look like ideal additions to a hair growth regimen.
However, the clinical safety story has become more complicated. These ingredients do not always behave like culinary herbs once they are concentrated, paired with absorption enhancers, and taken daily in supplement form. A botanical extract can deliver pharmacologically meaningful exposure to the liver, even when the label still reads like a wellness product.
This is not only a theoretical concern. NIH LiverTox now classifies ashwagandha as a likely cause of clinically apparent liver injury, while turmeric/curcumin is described as a well-documented cause of clinically apparent liver injury, particularly in high-bioavailability supplement forms1,2.
For practitioners working with individuals experiencing hair loss, the question becomes whether a concentrated hair supplement could be quietly adding systemic stress at the exact moment the follicle needs metabolic stability.
Hair Follicles Depend on Healthy Liver Function
To understand why certain supplements may influence hair shedding in unexpected ways, it is important to recognize the central role the liver plays in maintaining the internal environment required for healthy hair growth.
Hair follicles are among the most metabolically active structures in the body. During the anagen (growth) phase, follicular matrix cells divide rapidly and require a continuous supply of nutrients, hormones, and energy substrates3.
Because of this high metabolic demand, the hair follicle is extremely sensitive to disturbances in systemic physiology.
The liver serves as the body’s primary metabolic hub and sits at the center of many of the processes that sustain follicular activity.
One of the liver’s key functions is nutrient metabolism and storage of macronutrients (amino acids, fatty acids, glucose) and micronutrients (iron, zinc, and several B-vitamins). If liver stress interferes with nutrient processing or availability, follicles may shift prematurely out of the growth phase4.
The liver also metabolizes and clears multiple hormones that influence hair follicles, including thyroid hormones, estrogens, and androgens5. Disruption of these metabolic pathways can affect anagen duration, hair shaft thickness, or the timing of follicular cycling6.
The liver also acts as a major detoxification organ of metabolic byproducts and environmental chemicals through a complex network of phase I and phase II detoxification systems4. When hepatic detoxification capacity becomes overwhelmed, oxidative stress and inflammatory signaling may increase. These inflammatory mediators can circulate systemically and influence the scalp.
Finally, the liver plays a crucial role in bile production, which is essential for the absorption of fat-soluble nutrients (Vitamins A, D, E, and K)4. These vitamins contribute to scalp barrier function, immune balance, and cellular differentiation within the hair follicle. Impaired bile flow or liver stress can indirectly influence the availability of these nutrients7.
For these reasons, hair health cannot be viewed in isolation from systemic physiology. When hepatic function is overloaded, even mildly, hair follicles may interpret this shift as a signal of metabolic stress.
A patient may not connect fatigue, darker urine, itching, nausea, or jaundice to a hair growth product. Yet those systemic signals may appear in the same window in which the follicle begins to shed from metabolic disruption.
Ashwagandha
Ashwagandha has become one of the most widely used botanical ingredients in modern dietary supplements. Traditionally used in Ayurvedic medicine, it is classified as an adaptogen, meaning it is believed to help the body adapt to physiological stress and restore systemic balance8.
In recent years, ashwagandha has increasingly appeared in hair growth supplements because of its potential effects on stress physiology, endocrine signaling, and inflammatory balance.
Theoretically, these properties make ashwagandha an appealing ingredient for hair health. Elevated cortisol can shorten the anagen phase of the hair cycle and increase the likelihood of telogen effluvium9. By helping regulate cortisol activity, Ashwagandha is often promoted to support hair growth indirectly through improved stress resilience.
The concern is that the same ingredient promoted for stress resilience now has a recognizable, if rare, liver-injury signal. The typical ashwagandha-associated presentation begins 2 to 12 weeks after starting supplementation and usually shows a cholestatic or mixed pattern of injury with jaundice and pruritus. Long-lasting jaundice can occur, and liver tests often take 1 to 4 months to normalize after discontinuation1.
That pattern is clinically important because it is not subtle. Patients in published cases have presented with fatigue, nausea, abdominal discomfort, dark urine, intense itching, and visible jaundice1,10.
A case series from Iceland and the U.S. Drug-Induced Liver Injury Network identified five adults with liver injury attributed to ashwagandha-containing supplements. The patients developed jaundice after 2 to 12 weeks of use, with cholestatic or mixed injury patterns and prolonged pruritus or hyperbilirubinemia lasting weeks; liver tests normalized within 1 to 5 months in the patients with follow-up10.
More severe outcomes have also been described in higher-risk patients. In a 2023 case series from India, investigators identified eight patients with single-ingredient ashwagandha formulation-related herb-induced liver injury among 23 patients evaluated for ashwagandha-associated liver injury. Five had underlying chronic liver disease; three developed acute-on-chronic liver failure and died on follow-up. This does not mean ashwagandha commonly causes fatal injury in healthy users, but it does show why the risk cannot be dismissed as harmless or merely theoretical11.
These cases do not occur in most individuals taking ashwagandha, particularly when used short-term and at moderate doses. NCCIH notes that ashwagandha may be safe for short-term use up to about 3 months, but there is not enough information to draw conclusions about long-term safety, and rare cases have linked ashwagandha supplements to liver injury12.
The pattern of liver injury reported in these cases is typically cholestatic or mixed hepatocellular, characterized by elevated liver enzymes such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST), along with increased bilirubin levels in some individuals13.
Symptoms may include:
- Fatigue
- Abdominal discomfort
- Dark urine
- Jaundice
Symptoms can take anywhere from weeks to months to appear, making it difficult to diagnose.
These do not occur in most individuals taking ashwagandha, particularly when consumed in traditional forms or moderate doses. However, several factors appear to increase the likelihood of hepatic stress in reported cases.
One of the most important considerations is concentration and extraction method. Modern supplements contain highly concentrated root extracts standardized for active compounds known as withanolides14. While these compounds drive the herb’s adaptogenic effects, concentrated extracts may expose the liver to levels of phytochemicals that differ significantly from traditional dietary intake.
For practitioners it is important to track that concentrated herbal extracts, especially when combined with other ingredients, may place additional demands on hepatic detoxification pathways in susceptible individuals.
Curcumin
Curcumin, the primary bioactive compound found in turmeric (Curcuma longa), is widely recognized for its anti-inflammatory and antioxidant properties. It modulates the nuclear factor kappa B (NF-κB) inflammatory pathway, cyclooxygenase enzymes, and oxidative stress cascades15.
The paradox of curcumin is that its weakness, poor natural bioavailability, became a supplement marketing strategy. Curcumin is poorly absorbed when taken orally, so manufacturers often combine it with piperine from black pepper or use lipid/nanoparticle delivery systems to increase systemic exposure2,16.
Piperine can make that change dramatic. In a human pharmacokinetic study, adding 20 mg of piperine to 2 g of curcumin increased curcumin bioavailability by 2000%17. That is valuable if the goal is higher absorption, but it also means the body is no longer handling ordinary dietary turmeric exposure.
This matters because turmeric-related liver injury has become much better defined in recent years. High-bioavailability forms of purified curcumin have been linked to several cases of liver injury and were discussed as a possible contributor to outbreaks of acute hepatitis with jaundice in Italy. The typical latency is 1 to 4 months, and reported cases often present with fatigue, nausea, poor appetite, dark urine, jaundice, and marked aminotransferase elevations, sometimes above 1000 U/L2.
The most dramatic U.S. signal comes from the Drug-Induced Liver Injury Network. In a 10-case series of turmeric-associated liver injury, 9 patients had a hepatocellular pattern, 5 were hospitalized, and 1 died of acute liver failure. Chemical analysis confirmed turmeric in all 7 available products tested; 3 also contained piperine. HLA typing showed that 7 patients carried HLA-B*35:01, suggesting a genetic susceptibility pattern18.
Regulators have also responded. Australia’s Therapeutic Goods Administration reported 18 liver-problem reports involving turmeric or curcumin products through June 29, 2023; 9 had enough information to suggest turmeric/curcumin may have caused the injury19.
Health Canada reviewed more than 60 international case reports involving oral turmeric- or curcuminoid-containing health products. Three deaths were reported, two of which were because of hepatotoxicity linked with oral turmeric or curcuminoid products, leading Health Canada to update risk-label information for licensed products20.
Turmeric as a culinary spice has a long history of use and is not the concern in typical food amounts. The safety signal is most relevant to oral supplement forms: concentrated curcumin, high-dose turmeric extracts, products modified for enhanced absorption, and formulations combined with piperine or other bioavailability technologies2,19.
When Hair Supplements Stack Liver-Active Compounds
Contemporary hair formulas include combinations of ingredients such as ashwagandha, curcumin, mushroom extracts, phytoestrogens, antioxidants, and herbal adaptogens, alongside traditional nutrients like biotin, zinc, and B-vitamins.
This situation becomes even more complex when supplements include ingredients designed to enhance absorption or alter metabolism, such as piperine. While these compounds can improve the effectiveness of certain ingredients, these absorption-enhancing technologies can change the pharmacokinetic behavior of multiple ingredients at once.
Individuals experiencing hair loss often take multiple supplements and prescription medications (finasteride) simultaneously, sometimes without realizing the degree of overlap between them. Over time, this layering can result in a high cumulative intake of herbal extracts and concentrated phytochemicals21.
When supplements and medications compete for the same detoxification enzymes, metabolic interactions may occur that alter how these compounds are processed.
The liver itself is remarkably resilient and capable of managing a wide range of metabolic demands. However, when the detoxification system becomes overloaded, the resulting metabolic stress can influence other systems in subtle ways.
Hair follicles are particularly sensitive to systemic changes in metabolic balance. When the body experiences increased inflammatory signaling, altered hormone metabolism, or reduced nutrient availability due to hepatic strain, the follicle may interpret this as physiological stress. The result can be premature transition of follicles into the telogen phase and increased shedding.
Importantly, these scalp changes do not necessarily indicate permanent hair loss. When the underlying stressor is addressed, the follicular cycle frequently stabilizes and normal growth can resume.
Clinical Implications for Trichologists
For trichologists evaluating patients with unexplained shedding or persistent scalp inflammation, the growing use of complex nutritional supplements introduces an additional layer of consideration.
The supplement history should now be more specific than simply asking whether a patient takes vitamins. Practitioners should ask about turmeric or curcumin capsules, black pepper extract or piperine, ashwagandha stress formulas, sleep supplements, hormone-support blends, liver detox products, mushroom extracts, and any recent changes in brands or dosages.
The timing also matters. Ashwagandha-associated liver injury often appears within 2 to 12 weeks, while turmeric-associated injury is often reported within 1 to 4 months1,2,18. A new shedding episode that develops after a new supplement routine should not automatically be blamed on the supplement, but the temporal relationship is important enough to document.
Practitioners should also screen for systemic warning signs, especially when shedding is accompanied by symptoms that do not fit a purely scalp-based condition.
Identifying stacking regimens can help explain cases in which hair shedding appears without a clear hormonal or genetic driver.
Inflammatory symptoms (itching, tightness, or localized redness) may indicate that the follicular environment is experiencing metabolic or immune stress. When these symptoms are present along with new supplement use, it can raise the possibility that systemic factors are influencing follicular cycling.
Hair loss in these scenarios may not be caused by a single ingredient alone. More often, the issue arises from cumulative metabolic load, where multiple compounds interact with hepatic metabolism.
When supplement-related stress is suspected, clinical management involves simplifying the patient’s regimen. Reducing the number of concentrated botanical ingredients allows the body’s metabolic systems to stabilize and help restore the follicular growth cycle over time.
Conclusion
Hair growth is deeply connected to systemic physiology, and the increasing popularity of complex nutritional supplements has introduced new variables into the landscape of hair health.
Ingredients such as ashwagandha and curcumin are widely used for their potential benefits related to stress regulation and inflammation control, and most individuals tolerate these compounds without issue.
However, the literature now supports a more urgent message: these ingredients are not automatically benign simply because they are botanical. Ashwagandha has documented cases of cholestatic or mixed liver injury with jaundice and pruritus, and turmeric/curcumin supplements – especially high-bioavailability formulations – have been associated with hepatocellular injury, hospitalization, and rare fatal outcomes1,10,11,18–20.
This does not mean that hair supplements or botanical compounds are inherently harmful. The issue lies in concentrated extracts, enhanced absorption technologies, stacked supplement regimens, long-term use, underlying liver vulnerability, and individual susceptibility.
For trichologists and hair health practitioners, this highlights the importance of viewing hair loss through a whole-body lens. Careful evaluation of supplement use, nutritional status, metabolic health, systemic stressors, and liver-related red flags can provide valuable insights when addressing unexplained shedding or inflammatory scalp conditions.
The take-home message is simple: a product designed to help hair grow should not quietly increase the body’s burden elsewhere. When the scalp is signaling stress, the supplement shelf deserves a closer look.
References
1. Ashwagandha. in LiverTox®: Clinical and Research Information on Drug-Induced Liver Injury (National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda (MD), 2012).
2. Turmeric. in LiverTox: Clinical and Research Information on Drug-Induced Liver Injury (National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda (MD), 2012).
3. Saleh, D., Nassereddin, A., Saleh, H. M. & Cook, C. Anagen Effluvium. in StatPearls (StatPearls Publishing, Treasure Island (FL), 2026).
4. Kalra, A., Yetiskul, E., Wehrle, C. J. & Tuma, F. Physiology, Liver. in StatPearls (StatPearls Publishing, Treasure Island (FL), 2026).
5. Cazzagon, N. et al. Sex Hormones and the Liver: Implications for Disease Progression and Hormonal Therapy. Liver Int 46, e70509 (2026).
6. Hasan, R. et al. Effects of Hormones and Endocrine Disorders on Hair Growth. Cureus 14, e32726.
7. Almohanna, H. M., Ahmed, A. A., Tsatalis, J. P. & Tosti, A. The Role of Vitamins and Minerals in Hair Loss: A Review. Dermatol Ther (Heidelb) 9, 51–70 (2018).
8. Mikulska, P. et al. Ashwagandha (Withania somnifera)—Current Research on the Health-Promoting Activities: A Narrative Review. Pharmaceutics 15, 1057 (2023).
9. Novak, M. A. et al. Hair Loss and Hypothalamic–Pituitary–Adrenocortical Axis Activity in Captive Rhesus Macaques (Macaca mulatta). J Am Assoc Lab Anim Sci 53, 261–266 (2014).
10. Björnsson, H. K. et al. Ashwagandha-induced liver injury: A case series from Iceland and the US Drug-Induced Liver Injury Network. Liver Int 40, 825–829 (2020).
11. Philips, C. A. et al. Ashwagandha-induced liver injury-A case series from India and literature review. Hepatol Commun 7, e0270 (2023).
12. Ashwagandha: Usefulness and Safety. NCCIH https://www.nccih.nih.gov/health/ashwagandha.
13. Lubarska, M. et al. Liver Dangers of Herbal Products: A Case Report of Ashwagandha-Induced Liver Injury. Int J Environ Res Public Health 20, 3921 (2023).
14. Yang, L., Chen, X. & Gao, Y. Efficacy of Different Concentrations of Withanolides in Ashwagandha Supplements for Insomnia and Enhancing Energy Level. Curr Dev Nutr 6, 881 (2022).
15. Hewlings, S. J. & Kalman, D. S. Curcumin: A Review of Its’ Effects on Human Health. Foods 6, 92 (2017).
16. Turmeric: Usefulness and Safety. NCCIH https://www.nccih.nih.gov/health/turmeric.
17. Shoba, G. et al. Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteers. Planta Med 64, 353–356 (1998).
18. Halegoua-DeMarzio, D. et al. Liver Injury Associated with Turmeric–a Growing Problem: Ten Cases from the Drug-Induced Liver Injury Network [DILIN]. Am J Med 136, 200–206 (2023).
19. Administration (TGA), T. G. Medicines containing turmeric or curcumin – risk of liver injury | Therapeutic Goods Administration (TGA). https://www.tga.gov.au/safety/safety-monitoring-and-information/safety-alerts/medicines-containing-turmeric-or-curcumin-risk-liver-injury (2023).
20. Summary Safety Review – Turmeric and Curcuminoids for Oral Use – Assessing the Potential Risk of Hepatotoxicity. https://dhpp.hpfb-dgpsa.ca/review-documents/resource/SSR1758121117867.
21. Navarro, V. et al. Liver Injury from Herbal and Dietary Supplements. Hepatology 65, 363–373 (2017).