In case you need a reason to smile today – researchers have found that having a positive attitude and sense of humor could play a vital role in living a longer, healthier lifestyle.

Investigators developed a questionnaire designed to identify certain genetically-based personality traits and used it to study 243 Ashkenazi Jewish adults between 95 and 107 years of age. The investigators chose this specific group because their genetic similarities would make it easier to account for genetic differences in personality, reported ABC News.

“The results indicated they had two things — a positive attitude for life, meaning they are optimistic, easygoing, extraverted, laughed more and expressed emotions rather than bottling them up,” said Dr. Nil Barzilai, a study co-author and director of the Albert Einstein College of Medicine’s Institute for Aging Research.

Barzilai added that the exact reason that personality influences longevity is unknown.

“We still need to find out what the cause-and-effect relationship is,” he said. “We don’t know if we can change longevity by having a positive attitude, or if achieving longevity causes a positive attitude.”

The study also found that participants were less neurotic and more conscientious than a representative sample of other Americans.

Previous research has also found that personality can undoubtedly affect a person’s physical health.

“There’s an interaction between personality and physiology,” said Dr. Gary Small, director of the UCLA Center on Aging. “It makes sense that being more positive causes less stress and seems to get people on the right track to live better.”