May 2016 in “Endocrine Abstracts” Proximal hair cortisol is a reliable tool for diagnosing Cushing's Syndrome.
Distal hair cortisol is not a reliable measure of early pregnancy cortisol levels.
30 citations
,
July 2023 in “Clinical Chemistry and Laboratory Medicine (CCLM)” Cortisone in hair is a more reliable indicator of stress hormone exposure than cortisol.
23 citations
,
August 2017 in “Scientific Reports” Darker hair may lead to higher cortisol readings, suggesting a need to adjust for hair color in studies.
501 citations
,
October 2008 in “Psychoneuroendocrinology” Hair cortisol levels can show increased stress during late pregnancy but only for up to six months.
August 2019 in “Journal of archaeological science: Reports/Journal of archaeological science: reports” Ancient hair can preserve hormones, revealing health and fertility insights.
January 2023 in “Research Square (Research Square)” Hair cortisol may be a good indicator of recent mood in people with bipolar disorder.
2 citations
,
December 2021 in “Scientific reports” Scalp hair sweating is a significant predictor of hair cortisol levels.
May 2023 in “Animal Reproduction Update” High levels of cortisol in hair show long-term stress which can lower fertility in animals.
November 2025 in “Journal of Laboratory Medicine” Chronic stress increased after lockdown, especially in young adults and females.
November 2025 in “Contraception” COC use doesn't increase hair stress hormone levels, but hair treatments may affect results.
33 citations
,
January 2017 in “Psychoneuroendocrinology” Hair dyeing and washing frequency do not affect hair cortisol levels.
1 citations
,
September 2016 in “Brain Behavior and Immunity” Hair cortisol levels can indicate stress and are affected by washing frequency, not cosmetic treatments.
157 citations
,
June 2015 in “Psychoneuroendocrinology” Hair cortisol and cortisone levels increase with age, are higher in diabetics, vary by gender, decrease with frequent hair washing, and are lower in winter.
122 citations
,
October 2010 in “Clinica Chimica Acta” Washing hair with water or shampoo lowers cortisol levels in hair.
22 citations
,
May 2019 in “Animals” High hair cortisol levels indicate stress in cows due to poor shelter conditions and health issues.
3 citations
,
November 2021 in “Stress” Girls had higher stress hormone levels during school due to social and emotional issues, while boys had higher overall hormone levels with slight changes when school started.
February 2026 in “Psychoneuroendocrinology” Lower family income is linked to more stress in parents and more behavior problems in children.
10 citations
,
November 2018 in “Developmental Psychobiology” Hair can effectively measure DHEA and testosterone levels in children.
23 citations
,
October 2008 in “Experimental and Clinical Endocrinology & Diabetes” Hair can show increased cortisol levels during late pregnancy.
19 citations
,
June 2020 in “General and comparative endocrinology” Hair cortisol is a reliable stress indicator in cattle but may not be valid for pigs.
September 2017 in “OhioLink ETD Center (Ohio Library and Information Network)” Caregivers had lower stress hormone levels than non-caregivers, suggesting caregiving stress affects the body differently.
1 citations
,
December 2018 in “IntechOpen eBooks” Human hair shows promise for non-invasive medical testing, but more research is needed to standardize its use.
Higher cortisol levels might be linked to worsening keratoconus.
January 2018 in “Belarusian State Pedagogical University repository (Belarusian State Pedagogical University)” Stress might trigger hair loss in alopecia areata, but more research is needed.
Hair hormone levels can indicate stress after a medically indicated abortion.
296 citations
,
October 2018 in “General and Comparative Endocrinology” Hair cortisol is a reliable way to measure long-term stress in animals.
January 2026 in “Western Journal of Nursing Research” Hair cortisol levels don't reliably indicate chronic stress in people with multiple sclerosis.
11 citations
,
May 2020 in “Frontiers in psychiatry” Child abuse is linked to higher BMI, but not because of hair cortisol or cortisone levels.
90 citations
,
July 2014 in “Conservation Physiology” Hair cortisol levels in brown bears can be affected by both long-term and short-term stress.