Research table: Hair dyes and breast cancer risk

This summary table contains detailed information about research studies. Summary tables are a useful way to look at the science behind many breast cancer guidelines and recommendations. However, to get the most out of the tables, it’s important to understand some key concepts. Learn how to read a research table.

Introduction: Most studies, including a meta-analysis that combined the results of 14 studies, have found no increased risk of breast cancer among women who use permanent hair dye.

However, some findings suggest women who use permanent hair dye may have a slight increase in risk. This topic is under study.

Learn more about hair dyes, hair relaxers and breast cancer risk.

Learn about the strengths and weaknesses of different types of studies.

See how this risk factor compares with other risk factors for breast cancer.

Study selection criteria: Prospective cohort studies and meta-analyses.

Table note: Relative risk above 1 indicates increased risk. Relative risk below 1 indicates decreased risk.

Study	Study Population (number of participants)	Follow-up (years)	Relative Risk of Breast Cancer in Women who Ever Used Hair Dye Compared to Those who Never Used Hair Dye, RR (95% CI)
Prospective cohort studies
Nurses’ Health Study [1]	117,200 (9,252 cases)	36	1.02 (0.98-1.07)
Cancer Prevention Study II (CPS-II) [2]	573,369 (number of cases not given)	7	0.95 (0.83-1.08)
Sister Study [3-4]	47,522 (3,380 cases)*	10	Hair dye use ages 10-13: 0.97 (0.78-1.20)
	46,709 (2,794 cases)*	8	Hair dye use during adulthood: 1.09 (1.01-1.17)
Shanghai Women’s Health Study [5]	73,366 (592 cases)	7	0.93 (0.78-1.09)
Meta-analyses
Takkouche et al. [6]	14 studies including 680,633 women (any hair dye use)		1.06 (0.95-1.18)
	9 studies (permanent hair dye use only)		0.98 (0.91-1.07)
	9 studies (intensive hair dye use)		0.99 (0.89-1.11)

NS = Not statistically significant

* All participants have a sister diagnosed with breast cancer.

References

1. Zhang Y, Birmann BM, Han J, et al. Personal use of permanent hair dyes and cancer risk and mortality in US women: prospective cohort study. BMJ. 370:m2942, 2020.
2. Thun MJ, Altekruse SF, Namboodiri MM, et al. Hair dye use and risk of fatal cancer in U.S. women. J Natl Cancer Inst. 86(3):210-215, 1994.
3. White AJ, Gregoire AM, Taylor KW, et al. Adolescent use of hair dyes, straighteners and perms in relation to breast cancer risk. Int J Cancer. 148(9):2255-2263, 2021.
4. Eberle CE, Sandler DP, Taylor KW, White AJ. Hair dye and chemical straightener use and breast cancer risk in a large US population of black and white women. Int J Cancer. 147(2):383-391, 2020.
5. Mendelsohn JB, Li QZ, Ji BT, et al. Personal use of hair dye and cancer risk in a prospective cohort of Chinese women. Cancer Sci. 100(6):1088-91, 2009.
6. Takkouche B, Etminan M, Montes-Martinez A. Personal use of hair dyes and risk of cancer: a meta-analysis. JAMA. 293(20):2516-25, 2005.

Updated 11/08/23