TLDR Hair cortisol levels can reflect salivary cortisol levels in humans.
The study validated the direct correlation between cortisol levels in 1-cm hair segments and salivary cortisol in healthy humans. Researchers collected saliva samples at three different times and hair samples 4 weeks later, measuring cortisol levels using high performance liquid chromatography tandem mass spectrometry. Significant correlations were found between salivary cortisol at different times and between hair cortisol and salivary cortisol at Time 2 and the average salivary cortisol. The results confirmed that blood-related diffusion is a biologically endogenous source of hair cortisol.
375 citations,
July 2006 in “Journal of Investigative Dermatology” Stress can worsen skin and hair conditions by affecting the skin's immune response and hormone levels.
32 citations,
January 2017 in “Physiology & Behavior” New hair growth corticosterone levels are higher in diabetic mice, indicating long-term stress.
16 citations,
January 2021 in “Frontiers in veterinary science” Pigs in farrowing crates and loose-housing systems showed no difference in chronic stress levels as measured by hair cortisol.
2 citations,
January 2013 in “Elsevier eBooks” The chapter explains the causes of excessive hair growth and masculinization in women and how to measure hormone levels related to these conditions.
151 citations,
December 2004 in “Annals of the New York Academy of Sciences” Congenital Adrenal Hyperplasia is a genetic disorder with two forms, causing symptoms like early puberty and severe acne, but can be identified through screening and treated with glucocorticoids.
19 citations,
September 2020 in “General and comparative endocrinology” Hair cortisol is a reliable stress indicator in cattle but may not be valid for pigs.
