Article

Effects of shampoo and water washing on hair cortisol concentrations

Neuroscience and Behavior Graduate Program, University of Massachusetts, Amherst, MA 01003-9271, USA.
Clinica chimica acta; international journal of clinical chemistry (Impact Factor: 2.82). 10/2010; 412(3-4):382-5. DOI: 10.1016/j.cca.2010.10.019
Source: PubMed

ABSTRACT

Measurement of cortisol in hair is an emerging biomarker for chronic stress in human and nonhuman primates. Currently unknown, however, is the extent of potential cortisol loss from hair that has been repeatedly exposed to shampoo and/or water.
Pooled hair samples from 20 rhesus monkeys were subjected to five treatment conditions: 10, 20, or 30 shampoo washes, 20 water-only washes, or a no-wash control. For each wash, hair was exposed to a dilute shampoo solution or tap water for 45 s, rinsed 4 times with tap water, and rapidly dried. Samples were then processed for cortisol extraction and analysis using previously published methods.
Hair cortisol levels were significantly reduced by washing, with an inverse relationship between number of shampoo washes and the cortisol concentration. This effect was mainly due to water exposure, as cortisol levels following 20 water-only washes were similar to those following 20 shampoo treatments.
Repeated exposure to water with or without shampoo appears to leach cortisol from hair, yielding values that underestimate the amount of chronic hormone deposition within the shaft. Collecting samples proximal to the scalp and obtaining hair washing frequency data may be valuable when conducting human hair cortisol studies.

Download full-text

Full-text

Available from: Amanda M Dettmer
  • Source
    • "The latter findings may be in line with the in vitro experiments on hair of humans and rhesus macaques because the captive subjects in the in vivo animal studies were not exposed to rain and presumably not to strong UV-irradiation either. A systematic HCC decrease along the hair shaft should only be expected if hair is frequently exposed to water (Hamel et al., 2011), or UV-light (Li et al., 2012). However, Macbeth et al. (2010) also found no systematic decline along the hair shafts of water and light exposed free ranging grizzly bears, which raises the question whether some animal hair is inert to systematic HCC decrease along the hair shaft. "

    Full-text · Dataset · Dec 2015
  • Source
    • "How the external environment impacts hair cortisol content is not well studied, and there are inconsistent reports on this subject in the literature. Repeated hair-washings in hot water and shampoo have been reported to decrease hair cortisol content by some, and this could perhaps be due to damage of the hair structure (Stout et al. 2007; Hamel et al. 2011; Li et al. 2012). Conversely, Kirschbaum et al. (2009), Manenschijn et al. (2011), and Stalder et al. (2012) found no significant differences in hair cortisol content in hair related to frequency of hair-washing or treatment. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Stress is known to contribute to overall health status. Many individuals in sub-Saharan Africa are believed to be stressed about their employment, income, and health. This study aimed to investigate hair cortisol as a biomarker of chronic stress in settlement communities in Kenya. Hair samples were collected from 108 volunteers from settlement communities in Kenya. An enzyme-linked immunosorbent assay technique was used to measure hair cortisol concentrations. In parallel, a health survey was completed. The mean ± SD for the cortisol concentration in the hair of volunteers from the settlement communities in Naivasha was 639 ± 300 ng/g, which was higher than found for a Caucasian reference group (299 ± 110 ng/g; one-way ANOVA, P = 0.0003). There were no differences in hair cortisol concentrations between members of slum settlements adjacent to large floriculture farms in Naivasha (Karagita, Kamere/Kwa Muhia/DCK, and Kasarani) compared with those well-removed from all floriculture in Mogotio (Mogotio and Westlands/Katorongot). However, hair cortisol concentrations were significantly higher in females, divorced volunteers, those who made below minimum wage, and those who reported feeling unsafe collecting water or using sanitation facilities within these 2 settlement groups. We found no evidence for increased chronic stress (measured by hair cortisol content) between members of slum settlements adjacent to versus distant to large floriculture farms. Cultural and socio-economic conditions that prevail in much of sub-Saharan Africa were found to be factors contributing to chronic stress.
    Full-text · Article · Jul 2014 · Canadian Journal of Physiology and Pharmacology
  • Source
    • "Com isso, percebe-se que o viés da pesquisa se deveria aos períodos longos entre uma coleta e outra. E, para controlar essa variável confundidora,Hamel et al. (2011)afirmam que se deve perguntar à pessoa avaliada qual a frequência com que lava os cabelos. Além disso, outros autores ressaltam a importância de que estudos assim sejam feitos em humanos, tendo em vista que os estudos preliminares foram realizados com macacos, cuja higienização tem uma especificidade diferente da humana.Qual a diferença entre cortisol capilar e os outros métodos? "

    Full-text · Article · Jan 2014
Show more