Impaired wound healing

• In 2009 the Journal of Psychosomatic Research published a review of 17 studies – all of which reported that psychological stress was associated with impaired wound healing. [Source]
• In 2003 Psychosomatic Medicine published a study of 47 patients undergoing surgery which found that greater perceived psychological stress was associated with poorer, more painful and slower recovery. [Source]

Gentle touch – reduced stress and anxiety

• In 2007 Evidence-Based Complementary and Alternative Medicine published a study in which 147 subjects with self-identified psychological problems saw significant improvement in stress, anxiety and depression scores after completing 4 one-hour ‘gentle touch’ healing sessions over a 4-6 week period. The greatest improvement was seen in individuals with the most severe symptoms. [Source]

Impaired immune response in children

• In 2014 the Journal of Immunology published a study based on 78 children which found that 5-year-old children with higher stress levels due to parental worries, lack of support, parenting stress and serious life events had an imbalance in immune responses compared to 5-year-old children with no family related stress. [Source]

IBS and ulcerative colitis

• In 2014 Annals of Gastroenterology published a meta-analysis of 7 studies which found that depression and anxiety were both highly prevalent in cases of both IBS and ulcerative colitis. [Source]

IBD and IBS

• In 2012 The American Journal of Gastroenterology published a study including 564 IBS patients and 126 IBD patients, which found that the psychological distress associated with IBD and IBS have a stronger negative effect on health-related quality of life than the gastrointestinal symptoms associated with the diseases. For this reason, the authors of the study note the importance of addressing the psychological symptoms of both syndromes. [Source]

Stress, forgiveness and mental and physical health

• In 2016 the Journal of Health Psychology published a study based on 148 young adults which showed that lower levels of forgiveness were associated with greater lifetime stress severity and uniquely predicted worse mental and physical health. [Source]

Meditation – Stress and anxiety reduction

• In 2014 JAMA Internal Medicine published an analysis of 47 trials and found that meditation can result in small to moderate reductions in psychological distress. [Source]
• In 2014 the Clinical Journal of Psychiatry published a trial in which 93 patients suffering from generalized anxiety disorder (GAD) were assigned to either an 8-week mindfulness-based stress reduction program or an 8-week stress management education program. While both programs lead to significant reductions in anxiety, the meditation-based program produced greater results overall. [Source]

Meditation –  Reduction in stress hormones

• In 2013 the Journal of the Medical Association of Thailand published a study in which 30 medical students saw a significant reduction in the stress hormone, cortisol after completing a 4-day mindfulness meditation program. [Source]

Isolation Tank – Reduced stress, anxiety and depression

• In 2014 BMC Complementary and Alternative Medicine published a study in which 65 participants were randomized to either a control-group or a flotation-tank treatment group consisting of 7 flotation sessions over a 12-week period. Post-treatment questionnaires revealed increased optimism, improved sleep quality and decreased anxiety, depression, stress and pain in the flotation group, with no significant changes recorded in the control group. [Source]
• In 2009 Pain Research and Management published an analysis based on 88 patients (from 3 separate studies) with chronic stress-related muscle tension pain, as diagnosed by a physician. The data showed an increased tolerance to experimentally induced pain after completing a course of 12 flotation treatments over a 7-week period. [Source]
• In 2001 Pain Research and Management published a study in which 20 patients with chronic stress-related muscle pain in the neck and back completed 9 flotation sessions over 3 weeks. Compared to a control group of 17 subjects, those in the flotation group had reductions in pain intensity, depression, and anxiety as well as increased optimism. Patients who underwent flotation also fell asleep more easily. [Source]

L-theanine – Reduced stress response

• In 2007 Biology and Psychology published a double-blind, placebo-controlled study involving 12 participants which showed that L-theanine reduced heart rate and immune response to a stress-related task more than a placebo. [Source]
• In 2016 Nutrients published a double-blind study in which 34 adults received either a L-theanine or a placebo one hour before engaging in a multitasking cognitive stressor. The L-theanine group had reduced salivary cortisol response, indicating anti-stress effects. [Source]

Ginseng

• In 2010 Nutrition Research and Practice published an animal study which showed that ginseng restored homeostasis and reduce stress response in rats. [Source]

Skin

• In 2015 Mechanisms of Ageing and Development published an animal study which found that mice submitted to psychological stress for 28 days had more wrinkled skin, with reduced thickness, collagen and elastin levels. [Source]

Ornithine – Stress reduction and improved sleep

• In 2014 Nutrition Journal published a study in which 52 adults with slight stress and fatigue received either a placebo or 400 mg/day L-ornithine for 8 weeks. Blood tests showed a significant reduction in the stress hormone, cortisol when compared to the control group. Participants in the ornithine group also experienced improved sleep and reduced anger. [Source]

Aromatherapy – Job-related stress

• In 2015 the International Journal of Nursing Practice published a study in which 53 nurses wore a small bottle of 3 percent lavender oil and 57 nurses in a placebo group wore bottles with no oil. After 3-4 days the number of stress symptoms in the lavender group decreased from 6.1 to 2.8 while no decrease in stress was seen in the placebo group. [Source]

Aromatherapy – Stress in adolescents

• In 2009 the Journal of Korean Academy of Nursing published a placebo-controlled crossover trial which found that essential oil inhalation was more effective than a placebo in reducing stress in a group of 36 female high school students. [Source]

Aromatherapy – Pain, depression, anxiety, and stress reduction

• In 2014 Biomed Research International published a study in which a 4-week aromatherapy program involving 88 participants was able to reduced pain, depression, anxiety and stress levels among older adults with chronic pain. [Source]

Yoga – Stress and Academic performance

• In 2009 the International Journal of Yoga published a study involving 301  adolescents which found that students who practiced yoga performed better in academics than students who did not practice yoga – likely due to a reduction in stress. [Source]
• In 2012 the International Journal of Yoga published a study involving 100 clinical dental students which found practicing yoga significantly reduced the stress levels before their first surgery. [Source]
• In 2011 the International Journal of Yoga published a study which found that 30 first-year college students who performed 35 minutes of yoga daily for 12 weeks had lower levels of stress hormones and reduced impairment in cellular immunity during an examination when compared to a control group of 30 students. [Source]

Yoga – Depression and Stress

• In 2013 the Indian Journal of Psychiatry published a study involving 54 patients which found that a greater number of depressed individuals who performed yoga had reductions in cortisol compared to a group treated with anti-depressant medication only. Additionally, in the yoga group cortisol drop correlated with antidepressant effect. [Source] 
• In 2012 the Iranian Journal of Nursing and Midwifery Research published a quasi-experimental study which found that a yoga program consisting of two sessions for 8 weeks was an effective strategy for coping with stress for a group of 34 intensive care unit nurses. [Source]

Acupuncture –  Reduced stress and anxiety in elderly individuals

• In 2010 Neuroscience Letters published a study which found that 6 acupuncture sessions reduced stress, anxiety and depression scores in young and elderly adults. T-cell (white blood cell responsible for immunity) count also increased, with greater concentration in the elderly group. [Source]

Acupuncture –  PTSD (post traumatic stress disorder)

• In 2007 The Journal of Nervous and Mental Disease published a study which found that acupuncture was similarly effective to group-based cognitive-behavioral therapy in treating PTSD. [Source]

Hypertension

• In 2009 Cadernos De Saude Publica published a meta-analysis based on 6 studies totaling 34,556 subjects. The results showed that individuals who had strong responses to stressors were 21 percent more likely to develop blood pressure increases. [Source]

Ashwagandha – Reduced Stress and Anxiety

• In 2012 the Indian Journal of Psychology Medicine published a double-blind clinical trial in which 64 adults with chronic stress were given either a placebo or 300 mg of high concentration ashwagandha root extract twice a day for 60 days. At the end of the study period the ashwagandha group showed a significant reduction in cortisol levels (stress hormone) and stress assessment scores compared to the placebo group. [Scores]
• In 2014 the Journal of Alternative and Complementary Medicine published a review of 5 studies – all of which found ashwagandha root was more effective than a placebo in reducing anxiety. However, the authors note that all studies exhibited a high risk of bias. [Source]

CoQ10  – Reduced Stress-Related Depression

• In 2013 Pharmacology Biochemistry and Behavior published an animal study which tested the effects of high-dose CoQ10 for 3 weeks on rats with induced stress. The authors found CoQ10 to possess anti-depressive activity while protecting regions of the brain from stress-induced DNA damage. [Source]

Acne

• In 2007 Acta Dermato-venereologica published a study based on 94 students with an average age of 15 which found a significant association between stress and acne severity, especially in males. [Source]
• In 2009 BioMed Central Public Health published a study which found that self-reported acne was significantly associated with mental stress and, among females, infrequent consumption of raw vegetables. [Source]

5-HTP

• In 2010 in Neuro Endocrinology Letters published a trial which found that 15 participants who experienced recent romantic break ups saw significant reductions in stress after 3 weeks and significant increases in brain serotonin levels after 6 weeks when treated with 12.8 mg 5-HTP twice daily. [Source]