Music can improve our productivity, boost our mood and even help us eat less—but only if we choose our playlist wisely. Here’s how to select music for…

Relaxing. Don’t assume that the slowest songs are best for relaxation—the most relaxing tempo for you will be the one that’s in sync with your brain waves.

Keep a list of songs that seem to calm you and with which you have an emotional connection, then use the Web site TempoTap.com to determine their beats per minute (BPM) or enter the song title and “BPM” into a search engine. If many songs on your list have similar BPM, that’s probably the tempo that’s in sync with your brain waves. Enter that number, “BPM” and “songs” into a search engine to turn up additional options for your personal relaxation playlist.

Albums featuring the sounds of nature, such as ocean waves, waterfalls and rain, also can help set aside the day’s problems and help you relax.

Falling asleep. People tend to put on very slow, calm songs when they want to sleep. It’s more effective to start with music that matches the current pace of your mind, then ease your way into slower music. So paradoxically, the first song you listen to when you want to calm down from a hectic day might have a tempo of 100 BPM or more. The calm songs should come later. Examples: Slow-paced songs for the final minutes before sleep include The Tokens’ The Lion Sleeps Tonight (61 BPM)…Etta James’s At Last (60 BPM)…and Ray Charles’s Georgia on My Mind (64 BPM).

Getting out of a bad mood. The very best mood boosters are songs that transport us back to a happy place and time in our life. What songs did you dance to at your wedding? What songs were on the radio or on your turntable during the happiest year of your life?

Waking up. Songs with a relatively fast tempo—upward of 100 BPM—can help our minds get into gear in the morning. Examples: I’m Too Sexy by Right Said Fred (120 BPM) and Seaside Rendezvous by Queen (168 BPM).

Eating. Slow songs that make us feel happy are best for mealtime—particularly instrumentals. Music with a slow tempo encourages us to eat slower, reducing the odds that we will overeat. Instrumentals reduce the risk of overeating, too—lyrics are particularly distracting to our minds, and distracted people sometimes overeat simply because they don’t realize how much they have already consumed. Music that makes us feel happy is a smart choice for meals because unhappy people are more likely to indulge in unhealthy comfort foods to cheer themselves up. Examples of instrumentals: Slow-paced selections from Beethoven, Mozart and Bach.

Staying awake. Very fast-paced music can be more effective than caffeine for remaining sharp when driving at night or performing mindless, repetitive tasks. The Web site RunningMusicMix.com is one place to find songs with high BPM. Examples: Many songs from the techno, dance and hip-hop genres have very high BPM. Or try Lindy Hop swing jazz (140 to 200 BPM). Other popular songs with high BPM include The Coasters’ Charlie Brown (131 BPM)…and Charlie Daniels’s Devil Went Down to Georgia (136 BPM).