Focus on the positive instead of the negative to improve your outlook -- and perhaps your health, too.

Story highlights

Focus on how much sleep you did get, rather than the hour you lost

If you skip the gym, make a list of the activities you accomplished

Practicing optimism can make you feel better on a daily basis

Health.com  — 

Researchers have been studying the placebo effect for decades – and there’s plenty of evidence it works. So much so that a 2010 survey of more than 400 docs found that a whopping 56% said they’d actually prescribed placebos to their patients. (Um, yikes.)

But researchers are now looking beyond sugar pills and sham injections. The amazing findings? Just thinking you got a great night’s sleep makes you function better.

In a new study in the Journal of Experimental Psychology, researchers hooked up 164 students at Colorado College to equipment that supposedly showed how much time they spent in rapid eye movement (REM) sleep, the high-quality stuff that makes you feel rested. (Spoiler alert: The machine did nothing.)

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One group of students was told they’d gotten above-average sleep; the other, that they’d gotten below-average sleep. Then both groups were given a test.

Here’s the kicker: Regardless of how well the students actually slept, those who were told they got quality sleep performed better than those who were told they slept badly.

Placebos seem to work in large part “because they are given by authority figures,” as study co-author Kristi Erdal explains.

But guess what? You can trick yourself and harness the power of the placebo effect all on your own. Here are three tricks to try:

Be more productive

The students in the placebo sleep study who thought they’d slept well were sharper when it came to cognitive function the next day.

And while you can’t hook yourself up to a machine that will give you a favorable (but fake) REM readout, you can re-frame how you look at your shuteye. Even if you didn’t log a solid eight hours, try to focus on how much rest you did get rather than stressing about the hour you lay awake.

Telling yourself that you feel rested – rather than whining about how tired you are – may actually make for a more productive day. Lying to yourself for the win!

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Get fitter

An unusual study on placebo effect and fitness found that people who were told they were getting exercise in their daily lives – in this case, a group of hotel maids – actually became healthier without increasing their activity outside their jobs.

In one month, the subjects lost an average of two pounds, lowered their blood pressure, and improved their body fat percentages. (This 2007 study inspired the Colorado College researchers to look at placebo sleep, according to Slate.)

Now, this isn’t an excuse to ditch working out altogether, but during those periods when you just really don’t have time for the gym, your health may benefit from making a list of all the ways you stay active during the day, like cleaning the house, taking the stairs, playing with your kids, or walking the dog.

Feel happier

“Thinking positively, which is an extension of the placebo effect, is related to a whole host of good health outcomes,” says Erdal.

Practicing optimism – rather than focusing on the negatives – does have the power to make you feel better on a daily basis.

One technique that can help: Create an optimistic collage. Pull together photos that give you something to look forward to (say, pictures of your dream vacation spot). Hang them near the bathroom mirror or use them as your computer screen saver so that you see them several times a day. Bonus: It’s way less risky than surfing Pinterest at work.

Why happiness is healthy

This article originally appeared on Health.com