Whether you use a soft pillow or a firm pillow, is really personal preference. Both types can offer you neck support, and you just have to choose what is the most comfortable. Some people prefer to have a softer pillow for sleeping whereas others like to have very firm rock hard, and no give to the pillow.
What is most important is that you have good neck support under your cervical spine. This can even happen with a softer type of a pillow. You just have to make the right choice.
One example of a gentler softer support pillow is call the Arc4life Natural Alignment Pillow- This pillow was made to be supportive but more gentler for users. It has two neck rolls on it, that are just softer. Often times when we have sensitivity in the neck, or neck pain we just want a soft fluffy pillow. The only problem is that you are not supporting your c spine. This can make things worse for you. Having a softer support pillow may be right for you in this case.
One example of a firm level type of support is the tri core family of neck pillow pillows. These pillows have the fiber really stuffed into them. One added benefit to a pillow that is more firm in nature, is that it will last longer too. The fibers will break down less. A firm pillow will not hurt your neck, if you are used to sleeping on a firm pillow. If you are not used it, expect some soreness, muscle tightness, muscle spasms and neck pain the next morning. To avoid this, only sleep with the pillow for a 1/2 hour to an hour the first night. Then slowly increase your usage.
So really it just comes down to personal preference. Just make sure you are supporting your neck while you sleep. That is very important.
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