There are *four hormones* which determine a human's happiness - *Endorphins, Dopamine, Serotonin, and Oxytocin*.
*Endorphins*. When we exercise, the body releases Endorphins. This hormone helps the body cope with the pain of exercising. We then enjoy exercising because these Endorphins will make us happy. Laughter is another good way of generating Endorphins. We need to spend 30 minutes exercising every day, read or watch funny stuff to get our day's dose of Endorphins.
*Dopamine*. In our journey of life, we accomplish many little and big tasks, it releases various levels of Dopamine. When we get appreciated for our work at the office or at home, we feel accomplished and good, that is because it releases Dopamine. This also explains why most housewives are unhappy since they rarely get acknowledged or appreciated for their work. Once, we join work, we buy a car, a house, the latest gadgets, a new house so forth. In each instance, it releases Dopamine and we become happy. Now, do we realize why we become happy when we shop?
*Serotonin* is released when we act in a way that benefits others. When we transcend ourselves and give back to others or to nature or to the society, it releases Serotonin. Even, providing useful information on the internet like writing information blogs, answering people's questions on Quora or Facebook groups will generate Serotonin. That is because we will use our precious time to help other people via our answers or articles.
*Oxytocin*, is released when we become close to other human beings. When we hug our friends or family Oxytocin is released. The "Jhadhoo Ki Jhappi" from Munnabhai does really work. Similarly, when we shake hands or put our arms around someone's shoulders, various amounts of Oxytocin is released.
Now, we can understand why we need to hug a child who has a bad mood.So, it is simple, we have to exercise every day to get Endorphins, we have to accomplish little goals and get Dopamine, we need to be nice to others to get Serotonin and finally hug our kids, friends, and families to get Oxytocin and we will be happy. When we are happy, we can deal with our challenges!