To avoid neck and back pain or injury, keep your neck and entire spine aligned and supported at night. (You should be in the same position you normally stand in -- only horizontal.) The right pillow will help you do that.

If you sleep on your back:
Look for a medium-firm pillow that will cradle your head and keep your head and neck level with your upper back and spine. It shouldn't be so thick or fluffy that your head is propped up or angled sharply away from your body.

If you sleep on your side:
Keep your head, neck and spine lined up by sleeping on a small or medium-size pillow that has a firm or medium-firm thickness. For optimum comfort, use a rolled-up towel or a neck roll to support the curve between your neck and shoulder.

If you sleep on your stomach:
Try a soft, thin pillow -- or none at all. Anything too large will throw your neck out of alignment. Caution: Some doctors warn against sleeping on the stomach since it curves your back too much and can irritate your neck.

Bonus tip!
Make your pillow last longer by fluffing it every morning and using a pillow protector or cover inside the pillowcase to shield it from dirt and dust. Replace your pillow if it's lumpy, flat or stained, has a bad odor or if the fill is leaking.

Know the life expectancy of your pillows