Previous studies using healthy samples have found that higher levels of self-compassion significantly associates with lower cortisol levels (Herriot et al., 2018), lower blood inflammation (interleukin-6; Breines et al., 2014), and lower salivary alpha amylase concentration (another marker of sympathetic nervous system activation; Breines et al., 2015), and including such measures could add valuable knowledge about self-compassion and biological processes underlying stress responding in recurrent MDD. This evidence concerns the gene IL6 and major depressive disorder.