Case Study

The Mood Study


Does momentary discomfort caused by stepping out of one’s comfort zone to try new things lead to greater long-term well-being? If yes, many are averse to this – but the long-term benefits may outweigh short-term discomforts. No pain, no gain!


We predicted that interventions that cause people to stray from their typical routine would result in temporary negative moods or heightened levels of anxiety. In spite of this, we thought that these same experiences would be remembered fondly over time, and potentially even improve long term well-being.

We assigned participants to one of two conditions in an app we created called (sample) size matters. In the treatment condition, users were provided instructions that encouraged them to try something new, increase their activity, foster social bonds, or eat healthy. Control condition participants received no instructions each morning. Participants in both conditions were asked to track their mood throughout each day at randomly selected times and to report their overall well-being once a week.


Those in the treatment condition were less happy on a day-to-day basis than those in the control condition. However, we found that on a weekly basis, there was no significant difference in life satisfaction.

Why it matters

While those who find intense exercise (for example) unpleasant may be less happy on the day that they exercise (and especially while they are exercising), this research suggests that they will not be unhappy over the long run. Thus, they may not need to make a tradeoff between happiness and health.