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Can Intermittent Fasting Cause Hair Loss? A Look Into A New Study

First Published Jan 14 2025
Last Updated Jan 19 2025
Ingredients
Natural Remedies
Researched & Written By:
Sarah King, PhD
Reviewed By:
Rob English, Medical Editor
Can Intermittent Fasting Cause Hair Loss? A Look Into A New Study

Article Summary

Intermittent fasting has gained popularity for its potential health benefits, but recent research highlights its possible impact on hair health. Studies on mice and humans suggest that fasting-induced metabolic shifts can slow hair growth and weaken hair shafts by depleting activated hair follicle stem cells (HFSCs) through oxidative stress. While intermittent fasting may pose risks for those concerned about hair loss, modifying fasting durations or incorporating antioxidants could help mitigate these effects. The takeaway? Fasting can benefit overall health, but it’s worth considering its implications for hair growth, especially if you’re already dealing with thinning hair.

Full Article

Intermittent fasting (IF) has gained significant popularity as a dietary strategy that alternates between periods of eating and fasting. While IF is known for potential benefits such as weight management, improved metabolic health, and cellular repair, one study published in Cell has raised concerns about its possible impact on hair health.

The emerging question is whether intermittent fasting might inadvertently contribute to hair loss. This concern stems from new studies suggesting a potential link between fasting patterns and slower hair growth or increased hair shedding. In this article, we will cover the importance of hair follicle stem cells (HFSCs) in hair health and dive into the new intermittent fasting research.

The Role of HFSCs in Hair Health

HFSCs are essential for maintaining hair health and regeneration. HFSCs are located in a specialized microenvironment called the bulge region of the hair follicle.[1]Kinde, M.Z., Mekuria, T.A., Gessese, A.T., Mengistu, B.A. (2024). Molecular mechanisms of hair follicle development. The Scientific World Journal. 25. 5259055. Available at: … Continue reading They are essential for: 

  1. Initiating new hair growth cycles.
  2. Producing progenitor cells that form the hair shaft.
  3. Maintaining the hair follicle structure.

HFSCs are regulated by a number of internal and external signals, including transcription factors and key signaling pathways like:

  • Bone morphogenetic protein (BMP): A signaling pathway that maintains the resting state (quiescence) and specialization (differentiation) of HFSCs. BMP signaling balances growth (anagen) and rest (telogen) phases in the hair cycle.[2]Cai, B., Zheng, Y., Yan, J., Wang, J., Liu, X., Yin, G. (2019). BMP2-mediated PTEN enhancement promotes differentiation of hair follicle stem cells by inducing autophagy. Experimental cell research. … Continue reading 
  • Forkhead Box C1 (FOXC1): A transcription factor essential for the maintenance and self-renewal of HFSCs. It regulates genes involved in the preservation of the HFSC niche.[3]Cao, S., Wang, Z., Gao, X., He, W., Cai, Y., Chen, H., Xu, R. (2018). FOXC1 induces cancer stem cell-like properties through upregulation of beta-catenin in NSCLC. Journal of Experimental & … Continue reading  
  • Nuclear Factor of Activated T Cells, Cytoplasmic 1 (NFATc1): A transcription factor maintaining HFSC quiescence by repressing proliferative signals.[4]Horsley, V., Aliprantis, A.O., Polak, L., Glimcher, L.H., Fuchs, E. (2008). NFATc1 balances quiescence and proliferation of skin stem cells. Cell. 132(2). 299-310. Available at: … Continue reading
  • Sonic hedgehog (Shh): A key signaling pathway involved in the activation of HFSCs during hair follicle regeneration. Shh signaling is critical for initiating hair follicle growth and morphogenesis.[5]Suen, W.J., Li, S.T., Yang, L.T.  (2019). Hes1 regulates anagen initiation and hair follicle regeneration through modulation of hedgehog signaling. Stem Cells. 38(2). 301-314. Available at: … Continue reading
  • Wingless-related Integration Site (Wnt): A signaling pathway that we have discussed a lot on Perfect Hair Health as it is pivotal for HFSC activation and hair follicle regeneration. Wnt signals stimulate the transition of HFSCs from a quiescent to an active state, driving the anagen phase of the hair cycle.[6]Xiong, J., Wu, B., Hou, Q., Huang, X., Jia, L., Li, Y., Jiang, H. Comprehensive analysis of LncRNA AC010789.1 delays androgenic alopecia progression by targeting microRNA-21 and the Wnt/ꞵ-catenin … Continue reading

HFSC Response to Metabolic and Nutritional Changes

HFSCs are highly responsive to metabolic and nutritional changes. Glutamine metabolism, in particular, is critical for HFSC activation and maintenance, serving as an important energy source for hair follicles. This metabolic pathway sits at the nexus of HF regeneration by promoting the production of HF regenerative signals and directly activating HFSCs.[7]Wang, G., Sweren, E., Andrews, W., Li, Y., Chen, J., Xue, Y., Weir, E., Alphonse, M.P., Luo, L., Miao, Y., Chen, R., Zeng, D., Lee, S., Li, A., Dare, E., Kim, D., Archer, N.K., Reddy, S.K., Resar, … Continue reading When HFs don’t have enough glutamine, they shift into a “low-energy” mode, which changes how they process energy and nutrients, slowing down several important metabolic processes in the cells.[8]Piccini, I., Sousa, M., Altendorf, S., Jiminez, F., Rossi, A., Funk, W., Biro, T., Paus, R., Seibel, J., Jakobs, M., Yesilkaya, T., Edelkamp, J., Bertolini, M. (2022). Intermediate hair follicles … Continue reading

Oxygen levels also significantly impact HFSC function. Research has shown that HFSCs can prolong their lifespan by switching their metabolic state and gene expression in response to low oxygen tissue concentrations.[9]Salehi, M.S., Khani, F.C., Ansari, s., Mokhtari, M.J, Dara, M., Bayat, M., Hooshmandi, E., Ashjazadeh, N., Borhani-Haghighi, A., Unal, G., Pandamooz, S. (2024). Hypoxic preconditioning prevents … Continue reading This metabolic flexibility allows HFSCs to adapt to changing environmental conditions and maintain their regenerative potential.

Vitamins like Vitamin A are also important in regulating HFSC activity, as they affect BMP and Wnt signaling. Retinoic acid and retinol, the main active metabolites of vitamin A, regulate various aspects of hair follicle function, affecting the hair cycle, wound healing, and melanocyte stem cells.[10]Tierney, M.T., Polak, L., Yang, Y., Abdusselamoglu, M.D., Baek, I., Stewart, K.S., Fuchs, E. (2024). Vitamin A resolves lineage plasticity to orchestrate stem cell lineage choices. Science. 383(6687) … Continue reading You can read more about vitamin A and its sometimes paradoxical effects on hair growth here.

The mTORC1 Pathway and HFSC Activity

The mechanistic target of rapamycin complex 1 (mTORC1) is a key cellular nutrient-sensing mechanism that plays a critical role in HFSC activation and hair growth. mTORC1 signaling is activated in HFSCs during the telogen-to-anagen transition, coinciding with HFSC activation. This timing is crucial for the initiation of the hair growth cycle.[11]Deng, Z., Lei, X., Zhang, X., Zhang, H., Liu, S., Chen, Q., Hu, H., Wang, X., Ning, L., Cao, Y., Zhao, T., Zhou, J., Chen, T., Duan E. (2015). mTOR signaling promotes stem cell activation via … Continue reading

One of the primary mechanisms by which mTORC1 facilitates HFSC activation is through the regulation of BMP signaling. mTORC1 signaling negatively affects BMP signaling, which typically suppresses HFSC activation. By counterbalancing this BMP-mediated repression, mTORC1 helps overcome the suppressive signals and promotes hair regeneration.

The importance of mTORC1 in hair cycle regulation is further evidenced by studies showing that inhibition or ablation of mTOR signaling in adult skin before the start of anagen leads to significantly delayed HFSC activation and an extended telogen phase.[12]Kellenburger, A.J., Tauchi, M. (2013). Mammalian target of rapamycin complex 1 (mTORC1) may modulate the timing of anagen entry in mouse hair follicles. Experimental Dermatology. 22(1). 77-80. … Continue reading

Crash Dieting and Hair Loss

Crash dieting can lead to significant hair loss through the pathogenesis of telogen effluvium, which typically occurs 2-5 months after the onset of severe caloric restriction and is characterized by diffuse hair shedding. This hair loss is primarily due to nutritional deficiencies and psychological stress caused by rapid weight loss.[13]Rajput, R.J. (2022). Influence of nutrition, food supplements and lifestyle in hair disorders. Indian Dermatology Online Journal. 13(6). 721-724. Available at: https://doi.org/10.4103/idoj.idoj_175_22

Telogen effluvium occurs when a large number of hair follicles prematurely enter the resting (telogen) phase of the hair growth cycle.[14]Goette, D.K., Odomo, R.B. (1976). Alopecia in crash dieters. JAMA. 235(24). 2622-2633. In crash dieters, this is triggered by:

  • Severe caloric restriction
  • Rapid weight loss
  • Nutritional deficiencies

Studies show that crash dieters can experience telogen counts of 25-50% compared to the normal 10-15%, resulting in noticeable hair shedding, which can persist for up to 6 months after starting the diet.[15]Malkud, S. (2015). Telogen Effluvium: A Review. Journal of Clinical & Diagnostic Research. 9(9).01-03. Available at: https://doi.org/10.7860/JCDR/2015/15219.6492 

Crash dieting often leads to deficiencies in essential nutrients crucial for HFSC function and hair growth. Protein, a primary component of hair, is often reduced during crash diets, resulting in weakened hair structure and reduced hair growth.[16]Guo, E.L., Katta, Rajani. (2017). Diet and hair loss: effects of nutrient deficiency and supplement use. Dermatology Practical & Conceptual. 7(1). 1-10. Available at: … Continue reading Iron deficiency, common in women, affects the hair growth cycle and can cause diffuse shedding.[17]Cheng, T., Fang, H., Wang, Y., Yang, Z., Wu, R., Yang, D. (2021). The diagnostic value of serum ferritin for telogen effluvium: a cross-sectional comparative study. Clinical Cosmetic and … Continue reading Zinc deficiency impairs protein synthesis and cell division in hair follicles, while lacking essential fatty acids can trigger telogen effluvium.[18]Asghar, F., Shamim, N., Farooque, U., Sheikh, H., Aqeel, R. (2020). 12(5). E8320. Available at https://doi.org/10.7759/cureus.8320 Vitamins A, C, D, and E are crucial for HFSC function, and their deficiencies can hinder hair growth.[19]Almohanna, H.M., Ahmed, A.A., Tsatalis, J.P., Tosti, A. (2018). The role of vitamins and minerals in hair loss: a review. Dermatology and Therapy. 9(1). 51-70. Available at: … Continue reading

These nutritional deficiencies have severe consequences for HFSCs. They impair stem cell proliferation and maintenance, reduce the ability of HFSCs to differentiate into hair follicle progenitor cells, and can trigger autophagy in hair follicle cells.[20]O’Conner. K., Goldberg, L.J. (2021). Nutrition and hair. Clinics in Dermatology. 39(5). 809-878. Available at: https://doi.org/10.1016/j.clindermatol.2021.05.008 Autophagy leads to the programmed breakdown of intracellular organelles, further compromising hair health.

The physiological stress induced by crash dieting can also compound the issue. Rapid weight loss and severe calorie restriction trigger survival responses in the body, prioritizing essential functions over hair growth.[21]Hadshiew, I.M., Foitzik, K., Arck, P.C., Paus R. (2004). Burden of hair loss: stress and the underestimated psychosocial impact of telogen effluvium and androgenetic alopecia. Journal of … Continue reading This metabolic stress is accompanied by increased oxidative stress. Moreover, severe caloric restriction can alter hormone levels, particularly thyroid hormones, which play an important role in hair growth regulation.[22]Lips, M.A., Pijl, H., van Klinken, J.B., de Groot, G.H., Janssen, I.M., van Ramshorst, B., Van Wagensveld, B.A., Swank, D.J., Dielen, F.V., Smit, J.W.A. (2013). Roux-en-Y gastric bypass and calorie … Continue reading

Intermittent Fasting and HFSC Function

So, this brings us to the focus of the article, a new in vivo study conducted in mice and a human clinical trial, indicating that IF inhibits hair follicle regeneration.[23]Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to … Continue reading  The researchers show that this effect is primarily due to metabolic shifts during fasting, where the body switches from glucose to fat utilization, leading to increased oxidative stress in HFSCs.

Key Findings

Mouse Study

  • Intermittent Fasting regimens:
    • Two fasting regimens, 16/8 time-restricted feeding (TRF) and alternate-day fasting (ADF), were tested and compared to an ad libitum (AL) feeding control.
    • Mice on these regimens exhibited significantly impaired hair follicle regeneration compared to AL feeding controls.
Intermittent fasting induces hair loss in mice.

Figure 1: Effect of fasting on hair regeneration after depilation. Mice in the TRF and ADF groups showed noticeably impaired hair regrowth.[24]Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to … Continue reading

  • Mechanism of Impairment:
    • IF selectively caused cell death (apoptosis) in activated HFSCs, while quiescent HFSCs and epidermal stem cells were unaffected. Furthermore, this apoptosis peaked at 16-24 hours during fasting and then reduced again with refeeding. But how does that work?

When fasting surpasses 16 hours, the body transitions from using glucose to relying on fat stores for energy, breaking these fats down into free fatty acids (FFAs) via lipolysis, a process regulated by stress hormones like corticosterone (the mouse equivalent of cortisol) and epinephrine. This shift compels hair follicle stem cells (HFSCs) to metabolize FFAs for energy through fatty acid oxidation (FAO). Although FAO generates energy, it also produces reactive oxygen species (ROS) due to electron “leaks” during mitochondrial activity. This oxidative stress overwhelms the HFSCs’ limited defenses, leading to cellular damage, stem cell death, and disrupted hair follicle regeneration.

Figure 2: Effect of fasting on apoptosis in the mouse hair follicle. Apoptosis (red) peaked during 16-24 hours of fasting before dropping again at the refeed.[25]Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to … Continue reading

    • This apoptosis was linked to interorgan communication involving the adrenal glands and dermal adipocytes, leading to lipolysis and apoptosis.
    • Fasting induced lipolysis in dermal adipocytes, releasing FFAs, which disrupted HFSC metabolism, increasing ROS and oxidative damage.
Intermittent fasting led to a state of oxidative stress in hair follicle stem cells.

Figure 3: Effect of fasting on oxidative stress and mitochondrial damage in HFSCs.[26]Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to … Continue reading

  • Long-Term Effects (8 months):
    • Chronic fasting led to HFSC depletion, baldness in mice, and hair follicle degeneration.
    • Increased fasting duration exacerbated the effects, with greater HFSC apoptosis and impaired hair regeneration. 
  • Countermeasures:
    • Enhancing antioxidant defenses with topical vitamin E or genetic overexpression of antioxidant enzymes mitigated HFSC apoptosis and restored hair regeneration.

Figure 4: Left. Vitamin E (VE) or genetic overexpression of catalase (CAT OE) rescued apoptosis after fasting. Right. Hair regrowth of mice receiving VE or CAT OE under alternate-day fasting.[27]Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to … Continue reading

Human Study

  • Clinical Trial:
    • 49 healthy men and women were randomized into the 18/6 time-restricted diet, the energy restriction diet (1,200 – 1,500 kcal/day), or a control group with a normal diet.
    • Hair was shaved in a 1 cm2 section, and then the length of hair regrown after three days was measured at Baseline and Endline. 
    • Human participants undergoing intermittent fasting showed a significant decrease in the speed of hair growth (18% compared to the control group).

Effect of intermittent fasting (TRD) on hair growth speed in the last three days of the study. Those in the intermittent fasting group showed significantly decreased hair growth compared to the control group. *p < 0.05, **p < 0.01, ***p < 0.001, n.s., not significant.[28]Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to … Continue reading

  • Mechanistic Parallels with the Mouse Study:
    • Human HFSCs treated with FFAs showed elevated ROS, mitochondrial damage, and apoptosis, similar to the findings in mice.

Figure 6: Effect of free fatty acid treatment on reactive oxygen species in human HFSCS. FFA treatment led to a significant increase in reactive oxygen species. *p < 0.05, **p < 0.01, ***p < 0.001, n.s., not significant.[29]Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to … Continue reading

    • Increased lipolytic hormone levels like corticosterone and epinephrine were observed in participants. This increase leads to fat breakdown and elevated FFAs around hair follicles,  increasing oxidative stress and hair damage.

Changes in (left) cortisol and (right) epinephrine in the control or fasting groups. The fasting groups showed an increase in both hormones, which led to an increase in fat breakdown and FFAs.[30]Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to … Continue reading

  • Observations on Hair Characteristics
    • While hair density did not show any significant difference, many of the hairs were shorter and thinner in diameter. 

So, what are the potential implications of this for those who want to try intermittent fasting?

Hair loss risks: People undergoing intermittent fasting may experience slower hair growth and thinner hair shafts due to the depletion of activated HFSCs. Furthermore, chronic or extended fasting might increase the risk of hair follicle degeneration. 

However, it is possible that incorporating antioxidants or modifying fasting durations to reduce oxidative stress could counteract hair loss. Shorter fasting durations, for example, with extended eating windows, could reduce the adverse effects on HFSCs and hair regeneration. Those concerned about hair loss might consider fasting regimens with shorter periods of extended fasting and include dietary or topical antioxidants to protect HFSCs. It should be noted that the antioxidant treatments were only conducted in mice, so we don’t know if a similar protective effect will be observed in humans.

Should I Avoid Intermittent Fasting if I Am Already Losing My Hair?

Well, we can’t give a definitive answer, but it doesn’t seem out of the realm of possibility. Ultimately, we will have to wait for future research to determine what effect intermittent fasting might have on those with hair loss disorders or hair thinning. However, if you do decide to undergo intermittent fasting to reap its other benefits, you could try incorporating antioxidants into your diet or applying topical vitamin E to potentially protect your HFSCs.

Final Thoughts

Intermittent fasting offers various health benefits, but its impact on hair health, particularly through its effects on hair follicle stem cells, raises valid concerns. While the evidence is still emerging, modifying fasting regimens and incorporating protective measures like antioxidants may mitigate potential hair growth issues. As always, those considering intermittent fasting should weigh the benefits against the potential risks before taking the dive. 

References

References
1 Kinde, M.Z., Mekuria, T.A., Gessese, A.T., Mengistu, B.A. (2024). Molecular mechanisms of hair follicle development. The Scientific World Journal. 25. 5259055. Available at: https://doi.org/10.1155/twsj/5259055
2 Cai, B., Zheng, Y., Yan, J., Wang, J., Liu, X., Yin, G. (2019). BMP2-mediated PTEN enhancement promotes differentiation of hair follicle stem cells by inducing autophagy. Experimental cell research. 385(2). 111647. Available at: https://doi.org/10.1016/j.yexcr.2019.111647
3 Cao, S., Wang, Z., Gao, X., He, W., Cai, Y., Chen, H., Xu, R. (2018). FOXC1 induces cancer stem cell-like properties through upregulation of beta-catenin in NSCLC. Journal of Experimental & Clinical Cancer Research. 6(37). 220. Available at: https://doi.org/10.1186/s13046-018-0894-0
4 Horsley, V., Aliprantis, A.O., Polak, L., Glimcher, L.H., Fuchs, E. (2008). NFATc1 balances quiescence and proliferation of skin stem cells. Cell. 132(2). 299-310. Available at: https://doi.org/10.1016/j.cell.2007.11.047
5 Suen, W.J., Li, S.T., Yang, L.T.  (2019). Hes1 regulates anagen initiation and hair follicle regeneration through modulation of hedgehog signaling. Stem Cells. 38(2). 301-314. Available at: https://doi.org/10.1002/stem.3117
6 Xiong, J., Wu, B., Hou, Q., Huang, X., Jia, L., Li, Y., Jiang, H. Comprehensive analysis of LncRNA AC010789.1 delays androgenic alopecia progression by targeting microRNA-21 and the Wnt/ꞵ-catenin signaling pathway in hair follicle stem cells. 13.782750. Available at: https://doi.org/10.3389/fgene.2022.782750
7 Wang, G., Sweren, E., Andrews, W., Li, Y., Chen, J., Xue, Y., Weir, E., Alphonse, M.P., Luo, L., Miao, Y., Chen, R., Zeng, D., Lee, S., Li, A., Dare, E., Kim, D., Archer, N.K., Reddy, S.K., Resar, L., Hu, Z., Grice, E.A., Kane, M.A., Garza, L.A. (2023). Commensal microbiome promotes hair follicle regeneration by inducing keratinocyte HIF-1a signaling and glutamine metabolism. Science Advances. 9(1). 7555. Available at: https://doi.org/10.1126/sciadv.abo7555
8 Piccini, I., Sousa, M., Altendorf, S., Jiminez, F., Rossi, A., Funk, W., Biro, T., Paus, R., Seibel, J., Jakobs, M., Yesilkaya, T., Edelkamp, J., Bertolini, M. (2022). Intermediate hair follicles from patients with female pattern hair loss are associated with nutrient insufficiency and a quiescent metabolic phenotype. Nutrients. 14(16). 3357. Available at: https://doi.org/10.3390/nu14163357
9 Salehi, M.S., Khani, F.C., Ansari, s., Mokhtari, M.J, Dara, M., Bayat, M., Hooshmandi, E., Ashjazadeh, N., Borhani-Haghighi, A., Unal, G., Pandamooz, S. (2024). Hypoxic preconditioning prevents oxidative stress-induced cell death in human hair follicle stem cells. Iranian Journal of Biotechnology. 22(3). E3888. Available at: https://doi.org/10.30498/ijb.2024.447077.3888
10 Tierney, M.T., Polak, L., Yang, Y., Abdusselamoglu, M.D., Baek, I., Stewart, K.S., Fuchs, E. (2024). Vitamin A resolves lineage plasticity to orchestrate stem cell lineage choices. Science. 383(6687) 7342. Available at: https://doi.org/10.1126/science.adi7342
11 Deng, Z., Lei, X., Zhang, X., Zhang, H., Liu, S., Chen, Q., Hu, H., Wang, X., Ning, L., Cao, Y., Zhao, T., Zhou, J., Chen, T., Duan E. (2015). mTOR signaling promotes stem cell activation via counterbalancing BMP-mediated suppression during hair regeneration. Journal of molecular cell biology. 7(1). 62-72. Available at: https://doi.org/10.1093/jmcb/mjv005
12 Kellenburger, A.J., Tauchi, M. (2013). Mammalian target of rapamycin complex 1 (mTORC1) may modulate the timing of anagen entry in mouse hair follicles. Experimental Dermatology. 22(1). 77-80. Available at: https://doi.org/10.1111/exd.12062
13 Rajput, R.J. (2022). Influence of nutrition, food supplements and lifestyle in hair disorders. Indian Dermatology Online Journal. 13(6). 721-724. Available at: https://doi.org/10.4103/idoj.idoj_175_22
14 Goette, D.K., Odomo, R.B. (1976). Alopecia in crash dieters. JAMA. 235(24). 2622-2633.
15 Malkud, S. (2015). Telogen Effluvium: A Review. Journal of Clinical & Diagnostic Research. 9(9).01-03. Available at: https://doi.org/10.7860/JCDR/2015/15219.6492
16 Guo, E.L., Katta, Rajani. (2017). Diet and hair loss: effects of nutrient deficiency and supplement use. Dermatology Practical & Conceptual. 7(1). 1-10. Available at: https://doi.org/10.5826/dpc.0701a01
17 Cheng, T., Fang, H., Wang, Y., Yang, Z., Wu, R., Yang, D. (2021). The diagnostic value of serum ferritin for telogen effluvium: a cross-sectional comparative study. Clinical Cosmetic and Investigational Dermatology. 10(14). 137-141. Available at: https://doi.org/10.2147/CCID.S291170
18 Asghar, F., Shamim, N., Farooque, U., Sheikh, H., Aqeel, R. (2020). 12(5). E8320. Available at https://doi.org/10.7759/cureus.8320
19 Almohanna, H.M., Ahmed, A.A., Tsatalis, J.P., Tosti, A. (2018). The role of vitamins and minerals in hair loss: a review. Dermatology and Therapy. 9(1). 51-70. Available at: https://doi.org/10.1007/s13555-018-0278-6
20 O’Conner. K., Goldberg, L.J. (2021). Nutrition and hair. Clinics in Dermatology. 39(5). 809-878. Available at: https://doi.org/10.1016/j.clindermatol.2021.05.008
21 Hadshiew, I.M., Foitzik, K., Arck, P.C., Paus R. (2004). Burden of hair loss: stress and the underestimated psychosocial impact of telogen effluvium and androgenetic alopecia. Journal of Investigative Dermatology. 123(3). 455-457. Available at: https://doi.org/10.1111/j.0022-202X.2004.23237.x
22 Lips, M.A., Pijl, H., van Klinken, J.B., de Groot, G.H., Janssen, I.M., van Ramshorst, B., Van Wagensveld, B.A., Swank, D.J., Dielen, F.V., Smit, J.W.A. (2013). Roux-en-Y gastric bypass and calorie restriction induce comparable time-dependent effects on thyroid hormone function tests in obese female subjects. European Journal of Endocrinology. 169(3). 339-347. Available at: https://doi.org/10.1530/EJE-13-0339
23, 24, 25, 26, 27, 28, 29, 30 Chen, H., Liu, C., Cui, S., Xia, Y., Zhang, K., Cheng, H., Peng, J., Yu, X., Li, Y., Yu, H., Zhang, J., Zheng, J.H., Zhang, B. (2025). Intermittent fasting triggers interorgan communication to suppress hair follicle regeneration. Cell. 188(1). 157-174. Available at: https://doi.org/10.1016/j.cell.2024.11.004
Sarah King, PhD

Sarah King, PhD

Dr. Sarah King is a researcher & writer who holds a BSc in Medical Biology, an MSc in Forensic Biology, and a Ph.D. in Molecular and Cellular Biology. While at university, Dr. King’s research focused on cellular aging and senescence through NAD-dependent signaling – along with research into prostaglandins and their role in hair loss. She is a co-author on several upcoming manuscripts with the Perfect Hair Health team.

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