Mary Ryerse and Tyler Nakatsu:

While it’s pretty intuitive to know our expressions of gratitude might benefit another person (and that’s enough motivation!), there are also many scientifically proven benefits of gratitude, including:

Gratitude opens the door to more relationships
Gratitude improves physical health
Gratitude improves psychological health
Gratitude enhances empathy and reduces aggression
Grateful people sleep better
Gratitude improves self-esteem
Gratitude increases mental strength