In the United States, Thanksgiving is celebrated

on the fourth Thursday of November and is a day set aside to give thanks for our many blessings.
But gratitude is something that we should strive to make a regular part of our life, because it is strongly and consistently associated with greater health and happiness. According to studies conducted over the past decade, adults who feel grateful have more energy, more optimism, more positive emotions, more social connections and more happiness than those who do not. In addition, their health improves, they deal better with adversity, and they build strong relationships. They're also less likely to be depressed, envious, greedy or alcoholics."
Robert Emmons, who is an expert on the psychology of gratitude, conducted an experiment where he randomly assigned participants one of three tasks and asked them to keep a short journal. The first group wrote five things that had occurred in the past week that they were grateful for (the gratitude condition). The second group did the opposite, writing five daily hassles (the hassles condition) and the third group (the events condition) simply wrote five events that occurred in the last week (neither positive nor negative).
After ten weeks, participants in the gratitude condition felt better about their lives as a whole and were more optimistic about the future. They had fewer symptoms of physical illness, fewer health complaints, reported sleeping better and even spent more time exercising.