Were you all smiles in your yearbook photos? If you happily grinned from ear to ear back in those school days, chances are you’ll be happier later in life.

A study done at the University of California, Berkley looked at 141 pictures of women in their college yearbook photos at age 21. The researchers then contacted these women at the ages of 27, 43 and 52 to see whether they were happy in life and love. What they found was that most of the women who genuinely smiled in their photos, (genuine smiles are when the muscles around your eyes involuntarily contort, ie. the crow’s-feet crinkle around your eyes) were happier with their lives and their relationships. Most of these women were married by 27 (or in happily committed relationships) and at 52 were still very satisfied with their marriages.  Those who expressed more positive emotion also had higher levels of positive personal well-being.

Why is this? Could it be that these girls were prettier than the other? It has been said that attractive people are happier and more successful than others. To asses this, the researchers went back through the original photos and noted that physical attractiveness had no effect on the positive outcomes of these women’s lives. A warm smile is inviting and gives the impression that an individual is caring and patient, and harmlessly encourages others to interact with her socially.

The study’s drawbacks are that it only used one picture from one period of time in these women’s lives. It was also a constrained setting – when a photographer says smile, you typically do – the results may vary with more candid pictures. And more research should be done including men in the research to provide a broader conclusion.

Being (or thinking) positively can have a dramatic effect on your general happiness and demeanor.  Help yourself get happy now: smile more, stay busy, hang out with friends or even go for a walk.