Coir or coconut fiber is fiber from the husk of coconuts. Among other uses, it is used as a natural bedding material.
Generally, coir is used in the middle and upper layers of mattresses to provide support or responsive softness by adding more or less density of material.
Those that are allergic or sensitive to foam, may find that this all-natural, non-toxic material is a good addition. It is important to note that coir mattresses may also have additives: such as cotton, wool, or foam so it is important to do your research to make sure those materials are safe.
Pros: Eco-Friendly, non-toxic, and all natural bedding.
Cons: Comfort is dependent on the craftmanship and quality of the coir material. Low quality bedding can be quite uncomfortable.
Mattress foam comes in multiple different types: memory foam, polyurethane, and latex. Memory foam is a type of polyurethane foam that has lower resistance so it reacts and slowly reforms when pressure is released. It generally makes up the surface layers of a mattress.
Polyurethane comes in multiple different forms - making it useful in the middle and base layers of many foam and memory foam mattresses.
Latex is the natural alternative to memory foam and polyurethane foams. It is created from sap from a rubber tree and is treated to create different densities to cover both soft and firm requirements. Like rubber, it is highly responsive and has a bounce that some sleepers love and some others hate.
Pros: Depending on the foam type, it can be quite comfortable, safe, and responsive.
Cons: Lower quality foams can break down quickly, causing sagging issues within only a few months or years.