The Science Behind Red Hair and Pain Tolerance: Exploring the MC1R Gene

Red hair, a rare trait found in approximately 2% of the global population, is more than just a distinctive physical characteristic. It is the result of a mutation in the melanocortin-1 receptor (MC1R) gene, which not only determines hair color but also plays a significant role in how individuals perceive pain. ¹

Hannah Fryer, science writer also known as the "fryrsquared" says, "being ginger does come with one particularly gigantic upside, which not a lot of people know about, because ginger people feel less pain. The reason why we have this colouring is because of mutation in the MC1R gene."

The melanocortin-1 receptor (MC1R) gene, part of the G-protein-coupled receptor family, is primarily known for controlling pigmentation by regulating the type of melanin produced in skin and hair. Research has shown that certain variants of MC1R, especially those found in red-haired individuals, also influence how people experience pain. ¹

A recent study by the National Institutes of Health (NIH) has identified a connection between red hair and pain tolerance. Researchers observed that mice carrying the red hair–associated MC1R gene variant showed a higher pain threshold, even when pigment production was inactive.

The study revealed that changes in levels of proopiomelanocortin (POMC), a precursor hormone, influenced how pain signals were processed. This shift favored the activity of opioid receptors, which help reduce pain, suggesting that the effect of the MC1R gene on pain perception operates independently of pigmentation.

The findings highlight a deeper biological role for the MC1R gene in regulating pain, with potential implications for developing more personalized approaches to pain management in clinical care. ²

A controlled study of young women compared those with red hair (and pale skin) to those with blond or dark hair in how they perceive experimentally induced pain.

The researchers evaluated pain thresholds using heat and pressure, then applied topical capsaicin to provoke heightened sensitivity (hyperalgesia). They found no significant differences in basic heat or pressure pain thresholds between groups, but the red-haired participants developed smaller pin-prick hyperalgesic areas after capsaicin exposure compared to non-redheads.

This suggests that red-haired individuals may show a reduced secondary pain sensitization response. In clinical terms, this difference points toward a central role of melanocortin receptors (MCRs) in regulating pain sensitivity—and it may have implications for how analgesics and pain therapies work in people with MC1R gene variants. ³

References:

1. Wolf Horrell, Erin M., John A. D’Orazio, and Stuart G. Jarrett. “MC1R Functions, Expression, and Implications for Targeted Therapy.” Journal of Investigative Dermatology 142, no. 2 (2022): 293–302. https://www.sciencedirect.com/science/article/pii/S0022202X2101441X#:~:text=MC1R%20belongs%20to%20a%20subfamily,et%20al.%2C%202015).

2. Andresen, Trine, Lars Arendt-Nielsen, Asbjørn M. Drewes, and Anne Estrup Olesen. “Pain Sensitivity and Experimentally Induced Sensitisation in Red Haired Females.” Scandinavian Journal of Pain 2, no. 1 (2011): 3–6. https://pubmed.ncbi.nlm.nih.gov/29914002/

3. Robinson, Kathleen C., Lajos V. Kemény, Gillian L. Fell, Andrea L. Hermann, Jennifer Allouche, Wei Ding, Ajay Yekkirala, Jennifer J. Hsiao, Mack Y. Su, Nicholas Theodosakis, Gabor Kozak, Yuichi Takeuchi, Shiqian Shen, Antal Berenyi, Jianren Mao, Clifford J. Woolf, and David E. Fisher. “Reduced MC4R Signaling Alters Nociceptive Thresholds Associated with Red Hair.” Science Advances 7, no. 14 (2021): eabd1310. https://www.nih.gov/news-events/nih-research-matters/study-finds-link-between-red-hair-pain-threshold

(Rh/ARC/MSM)