Recent research in psychology suggests that 50% of happiness is determined by genetics. What positive psychologists refer to as a “happiness set point”. That’s why some people are almost always happier than others. You can thank or blame your parents and their parents for your particular happiness set point.

The same research suggests that 10% of our happiness is the result of life circumstances like marital status, occupation, and income. Most of the time, good or bad events, like getting a dream job or losing a pet affect our well-being, but only temporarily. Eventually, we adapt to the good and bad and our level of happiness returns to where it was before.

The remaining 40% results from “intentional activity” or our daily decision making. The conventional wisdom here is to 1) engage in positive self reflection; 2) avoid social comparison; 3) be optimistic; 4) pursue meaningful goals; and 5) practice gratitude.

Social scientists routinely privilege the mind over the body; consequently, three things are almost always missing from the conventional wisdom—physical activity, fruits and vegetables, and adequate sleep. I’m no Dr. Oz, but my hunch is those are every bit as important as the previous five. In fact, I suspect they account for half of my “non-genetically-determined” happiness, or half of half of my total well-being.

And I’m not unique in this regard. The more people make exercise, nutritious food, and sleep building blocks of their daily lives, the happier they will be.