If you are thinking of buying a new mattress and are considering foam, I know you are as confused as the rest of us. I started my search for what to purchase by looking for definitive studies on the pros and cons of memory foam vs latex. And there aren’t any. Well, none that I could find. The reason, as suggested by sleep specialist Donna L. Arand, Ph.D. is that sleep is a subjective experience. Yes, movement — or lack thereof — during the night, and the number of times the subject wakes can be measured but the frequency of these actions can’t be directly attributed to the mattress.
So, it all comes down to which one you prefer. But there are some considerations you might want to look at before you go shopping.
Memory foam is made from a petroleum-based product. It has a smell but that smell goes away. If it concerns you, leave the product outside for a few days. Shower curtains and plastic bags also off-gas; actually everything off-gasses and just because you can smell something doesn’t mean it’s dangerous. Then there is the other side of the coin: there are several very dangerous odorless gasses present in many homes. ( One estimate I read is that one in 15 new homes have unacceptable levels of radon.) Again, I couldn’t find any definitive studies on the risks of using a memory foam mattress. Less than 2% of memory-foam purchases are returned because of lingering door.
Making latex — which is pure rubber — into mattress foam often includes the incorporation of man-made ingredients which add to the softness of the mattress and reduces the cost, resulting in three types of latex foam: 100% latex, blended, and synthetic. Unless the whole mattress is pure latex, with no additives or layers of other products — like memory foam — the mattress is not 100% latex. You may see “natural” latex, indicating that there are additives which are not man-made products, e.g. soy oil is natural, but is an additive used to decrease price. Blended is obvious, as is synthetic.
You may see ‘Dunlop’ or ‘Talalay’ with reference to latex foam; it refers to a manufacturing method and that process can affect the softness of the foam. Love this analogy from dwarfparents.com: “Talalay is like angel food cake while Dunlop is like pound cake.”
The degree of softness of foam is listed as IDL. If I explain what that is here, you will glaze over and go away. But you should know what it is, so please take 5 minutes before you go mattress shopping and read Jessica Jones’ explanation on the Sleep Judge website: https://www.thesleepjudge.com/understanding-indentation-load-deflection-guide/.
The warmth of your body causes memory foam to conform to your shape; after you move, the foam must return to room temperature to release the shape. You will sink further into a memory foam mattress than a latex one and you will continue to sink in as you sleep. With latex, the pressure of your body creates the indentation; when you get up, the latex quickly springs back to shape.
Latex will help you stay cooler during a warm night than memory foam. But the mattress cover and your sheets actually control more of this temperature perception; you should not sleep directly on any mattress and a barrier of natural fibers will keep you cooler than polyester. Top choice? A linen-covered wool mattress cover under good quality cotton or linen sheets. With cotton, linen or silk jammies, of course.
Latex does not harbor moisture well, therefore it is quite resistant to mold and mildew. It is a renewable resource and is considered hypoallergenic. Can’t say any of these things about memory foam.
Take your time. Read some. Learn some. Test lots. You don’t want to make a mistake on this one.