There are many types of mattresses, produced with different materials and with different degrees of rigidity. There is no better model for everyone, so the choice should be made based on some parameters (weight, preferred sleep position, ambient temperature).
If the mattress is very rigid the body will not adhere to it completely. This allows better ventilation on the one hand, but on the other hand results in a non-optimal body weight distribution: the weight is not well distributed over the entire surface. In a very soft mattress the body tends to sink, the feeling of heat increases because there is no air passage. The column is not adequately supported. Thus it is recommended to buy a mattress for shoulder pain with perfect care. As for the thickness of the mattress, it should never be less than 12 cm, regardless of the stiffness and material of which it is composed.
Your habits and weight
For those who sleep in a supine position, lying on their backs, a stiffer mattress that gives the right support to the column is the best choice. Who sleeps on the side can instead opt for a less rigid mattress, which allows the shoulder to sink a bit ‘to allow a comfortable position.
Body weight is also important because different weights need different supports. For heavier people, stricter mattresses are needed that provide good support during sleep; in a soft mattress they would collapse. Those with a slender body need a more flexible mattress, on which the body can adhere well.
Instead of choosing a single mattress that represents a compromise between their different needs, they can opt for two single mattresses that have different degrees of rigidity, so both will have the correct support during rest.
Latex is a natural emulsion obtained from the rubber plant, used as primary compound for the production of mattresses. It can also be synthetic, and there are models composed of a mix of natural and synthetic latex. The mattresses of this material offer a rather stiff support but at the same time they are very flexible and adapt to the contours of the body distributing the pressure evenly.
With these materials the air circulation is lower, so the body heat tends to remain imprisoned in the mattress, which makes them suitable for people who are cold or in cold climates. Foam mattresses are usually lighter than others, which makes them easy to carry and handle an important feature especially if it is a double model.