Interesting. A 2018 systematic review in 'Psychology, Health and Medicine'.
The abstract reads: 'The review was conducted for all English, Portuguese and Spanish language articles published between 2005 and 2015. Independent investigators analysed 42 studies concerning human psychoneuroimmunology-based interventions. Decreased levels of cortisol, epinephrine and norepinephrine (stress-related hormones) were associated to interventions like yoga, meditation, tai chi, acupuncture, mindfulness, religious/spiritual practices, cognitive behaviour therapy, coping and physical exercises. Moreover, those interventions were also associated with reductions in inflammatory processes and levels of pro-inflammatory cytokines in cancer, HIV, depression, anxiety, wound healing, sleep disorder, cardiovascular diseases and fibromyalgia. Despite the associations between PNI variables and clinical/therapeutic interventions, only one study evidenced significant effects on a disease progression'.