TY - JOUR
T1 - Impact of hair type, hair sample weight, external hair exposures, and race on cumulative hair cortisol
AU - Moody, Shannin N.
AU - van Dammen, Lotte
AU - Wang, Wen
AU - Greder, Kimberly A.
AU - Neiderhiser, Jenae M.
AU - Afulani, Patience A.
AU - Willette, Auriel
AU - Shirtcliff, Elizabeth A.
N1 - Funding Information:
Participants in Study 2 were recruited from a larger research project, Abriendo Caminos, that was supported by the Agriculture and Food Research Initiative Competitive grant no. 2015–68001–23248 from the US Department of Agriculture National Institute of Food and Agriculture under the Childhood Obesity Prevention Challenge Area, and led by Margarita Teran-Garcia, MD, PhD (PI) at University of Illinois at Urbana-Champaign. Kimberly Greder, PhD, Iowa State University, served as the PD for Abriendo Caminos in Iowa. Collection and analysis of hair cortisol data for Study 2 was supported by the College of Human Sciences Collaborative Seed Grant Program (Kimberly Greder, PI; Marian Kohut, Co-PI; Elizabeth Shirtcliff, Co-PI) and a Strategic Initiative Grant from the Vice President for Extension and Outreach at Iowa State University (Kimberly Greder (PI), Himar Hernandez (Co-PI).
Funding Information:
Participants in Study 1 were recruited from the Kenya Study and was supported by the Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health under Award Number R00HD093798 . The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/8
Y1 - 2022/8
N2 - The biomarker cortisol assesses the impact of biopsychosocial stressors that activate the stress response system. Hair has emerged as a valid and non-invasive means of gauging cumulative cortisol deposited over month-long periods of time. Established protocols for the extraction of hair cortisol are being validated and refined in humans, yet methodological information about hair characteristics on cortisol remains limited. In addition to external hair exposures (e.g. dye, time spent outside), we examined hair categorization or type (e.g. kinky, straight) by extending a hair typing methodology for scientific use that is currently popular among hair care professionals. We then examined the interaction between hair type and race on cortisol levels with a hair questionnaire. Three studies were pooled to investigate how sample weight, hair type, race, heat exposures, and hair treatments impacted cumulative hair cortisol concentrations. Study 1 consisted of Adult Kenyan Medical Workers (N = 44); Study 2 Mexican and Mexican Americans (N = 106); and Study 3 American Youth (N = 107). We found significantly higher cortisol in 5 mg of hair when compared to larger sample weights, and higher cortisol in those who spent more time outdoors. Cortisol concentrations differed between racial groups and varied by hair type; moreover, there were directional differences in cumulative cortisol from straighter to curlier hair types which depended on racial group. In addition to demonstrating the impact of relatively novel control factors like hair sample weight, outdoor exposure, and hair type, the present study illustrates the importance of disentangling hair type and race to understand variability in cumulative hair cortisol. These influences should be included in future studies that measure hair cortisol.
AB - The biomarker cortisol assesses the impact of biopsychosocial stressors that activate the stress response system. Hair has emerged as a valid and non-invasive means of gauging cumulative cortisol deposited over month-long periods of time. Established protocols for the extraction of hair cortisol are being validated and refined in humans, yet methodological information about hair characteristics on cortisol remains limited. In addition to external hair exposures (e.g. dye, time spent outside), we examined hair categorization or type (e.g. kinky, straight) by extending a hair typing methodology for scientific use that is currently popular among hair care professionals. We then examined the interaction between hair type and race on cortisol levels with a hair questionnaire. Three studies were pooled to investigate how sample weight, hair type, race, heat exposures, and hair treatments impacted cumulative hair cortisol concentrations. Study 1 consisted of Adult Kenyan Medical Workers (N = 44); Study 2 Mexican and Mexican Americans (N = 106); and Study 3 American Youth (N = 107). We found significantly higher cortisol in 5 mg of hair when compared to larger sample weights, and higher cortisol in those who spent more time outdoors. Cortisol concentrations differed between racial groups and varied by hair type; moreover, there were directional differences in cumulative cortisol from straighter to curlier hair types which depended on racial group. In addition to demonstrating the impact of relatively novel control factors like hair sample weight, outdoor exposure, and hair type, the present study illustrates the importance of disentangling hair type and race to understand variability in cumulative hair cortisol. These influences should be included in future studies that measure hair cortisol.
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U2 - 10.1016/j.psyneuen.2022.105805
DO - 10.1016/j.psyneuen.2022.105805
M3 - Article
C2 - 35687978
AN - SCOPUS:85131512106
SN - 0306-4530
VL - 142
JO - Psychoneuroendocrinology
JF - Psychoneuroendocrinology
M1 - 105805
ER -
