Some try a medicinal cure. Others imbibe a robust nightcap. And, of course, many count those unending lines of sheep. But a good bet to beat insomnia is one denied to the cranky souls among us. Namely, look on the bright side of life.

Research led by a University of Illinois scientist found people who reported higher levels of optimism tended to sleep better, with fewer symptoms of insomnia and less sleepiness during the day.

The study looked at more than 3,500 people between the ages of 32 and 52 and quizzed them on their outlook on life. Participants were asked to rate on a five-point scale whether they agreed or disagreed with certain statements. One example: “I’m always optimistic about my future.” Another was, “I hardly expect things to go my way.”

Then everyone reported on their sleep quality and duration five years apart.

The paper, published in the journal Behavioral Medicine, notes that optimists might have fewer ruminations about life’s worries when they’re falling asleep. They aren’t tossing and turning thinking about all their problems at work or the ups and downs of their life.

And good sleep is good health, as insomnia has been associated with higher risk of obesity, hypertension and even death.

One researcher said optimists are focused on what she called “active problem-focused coping” and looking at stressful events in more positive ways. Call it the glass half-empty, half-full paradigm.

These same researchers in earlier work also found optimists age 45 to 84 were more likely to have ideal heart health.

The overarching lesson in all this? You shouldn’t let life get you down. Don’t worry. Be happy. And sleep tight.