The following studies demonstrate the affect gratitude has on one’s mental and physical health.

• Writing a gratitude letter and counting blessings had “high utility scores and were associated with substantial improvements in optimism” (Huffman, Dubois, Healy, Boehm, Kashdan, Celano, Denninger, & Lyubomirsky, 2014).
• Gratitude letter writing leads to better mental health in adult populations seeking psychotherapy (Wong, Owen, Brown, Mcinnis, Toth, & Gilman, 2016).
• Gratitude buffers people from stress and depression (Wood, Maltby, Gillett, Linley, & Joseph, 2008).
• Positive reframing underlies the relationship between trait gratitude and a sense of coherence. A sense of coherence is how confident a person feels about potential life outcomes. It is the degree to which a person feels optimistic and in control of future events (Lambert, Graham, Fincham, & Stillman, 2009).
• Patients who expressed optimism/gratitude two weeks after an acute coronary event had healthier hearts (Huffman, Beale, Beach, Celano, Belcher, Moore, Suarez, Gandhi, Motiwala, Gaggin, & Januzzi 2015).
• Gratitude and spiritual wellbeing are related to positive affect, sleep quality, energy, self-efficacy, and lower cellular inflammation (Mills, Redwine, Wilson, Pung, Chinh, Greenberg, Lunde, Maisel, & Raisinghani, 2015).
• Gratitude may enhance peace of mind, reduce rumination, and have a negative effect on depressive symptoms (Liang, Chen, Li, Wu, Wang, Zheng, & Zeng, 2018).