Some people prefer a firmer mattress, while others prefer something with more moldability, like a foam mattress, but generally, you want a mattress that’s in good condition, says Dr. Grimes. If you’re sleeping on a sagging mattress and you’re starting to have problems sleeping, rotating the mattress or getting a mattress topper could help.
Your body will react to mattresses in different ways. If you’re lying flat on a hard mattress, your spine may be neutral, with no bending or twisting. This may be beneficial for someone who needs extra support. But if you’re lying flat on your back on a soft mattress, your lumbar spine might bend forward like you’re looking down, which is called “flexion,” says Dr. Smith. This compresses the discs, and that can make disc pain worse. If you’re lying on your stomach in a soft bed, that could extend your back. This position might feel good for the low back in people whose spines bend forward, but it could cause discomfort for others.
Pillows should also help you achieve a neutral spine, adds Dr. Smith. Stomach sleepers usually prefer a thin pillow so their neck isn’t contorted, while back and side sleepers can tolerate a thicker pillow as long as their spine stays neutral.