How do you know if you need a new pillow?

Here's a simple test: fold your pillow in half, put a book on it and let go. If the pillow stays folded, you need a new one.

Now comes the hard part. Good Housekeeping Research Institute Textiles Director Kathleen Huddy says consider the options when buying a new pillow.

The institute's top pick was the Aller-Ease Washable Allergy Protection ($12).

"It's a great price, and its allergy protection is a bonus," she said.

For their down and feather pillow pick, the institute picked Land's End Essential Goose Down ($79), which is washable.

"It kept its smooth seams and soft texture after many washings," said Huddy.

When it comes to memory foam pillows, the institute says the Leggett & Platt Home Collection Brisa ($55) came out on top

"It bounced back after being under a 30-pound weight overnight," Huddy said.

And among all the down foam pillows on the market, the institute picked Stearns & Foster down Caress ($100).

"The latex core is surrounded by down clusters and covered with a cotton silk fabric," said huddy.

Maintain your pillows by washing them once a season or about three times a year, according to the manufacturer's directions.