It's no secret that a comfortable, supportive pillow is an important ingredient in a good night's sleep. But what may come as a surprise is how often you're supposed to invest in a new one. According to the Sleep Foundation, you should replace your pillow every one to two years for optimal R&R.

Curious about the reasoning behind these guidelines? Us too — so we reached out to experts for some pillow talk. Here, we reveal what can go wrong if your pillow dates back to the Bush administration, plus signs it's time for a new pillow and tips to extend that two-year lifespan a little longer.

Your Sleep Could Suffer

A squashed-down pillow can cause tense, achy muscles.

Pillows lose their loft over time, especially if you don't wash them re