The definition of ergonomics probably isn’t what you might guess based on how you’ve seen it used. The word actually refers to the study of peoples’ efficiency in their work environment. It has nothing to do with your back, spine or posture… at least, not in its plainest application.
How it relates to furniture — i.e., an ergonomic chair, ergonomic bed, etc — has to do with how efficiently the object works to provide the necessary support your body requires. Another way of thinking about it is this: the design of furniture has shifted, over time, to be less efficient in it’s most basic function. Ergonomic furniture is manufactured to reverse this trend and give your body the best support possible, to promote better function and a higher degree of comfort.
You may run across a product labeled or titled as being an ergonomic bed, but you should pay close attention in evaluating whether that’s truly what it is. A bed that’s truly of ergonomic design should allow for you to be in a neutral, side-lying position without the usual spine-twisting issue (this is part of what makes sleeping on one’s side less than ideal). The truly ergonomic bed will have a cut-away to support the lower arm underneath the body while shoulders and head are well-supported above. This also allows the shoulders to rest in a neutral position rather than the inward roll that’s most common.
Other marks of a truly ergonomic bed include a mattress with a wedge shape to it, which keeps the head elevated and reduces narrowing of airways and thus also helps prevent sleep apnea.
As is the case with any bedding, there is also the concern of treated foam. If you’re buying a bed that utilized foam products at all, this is not a time to skimp on expenses – the cheaper the foam products, the more likely they are to be treated. Treated foam results in out-gassing… spend the extra money for pure foam products whenever possible.
A good adjustable bed doesn’t necessarily mean it has to be ergonomic through and through, as defined above. If you’re having problems sleeping at night, it could be any number of factors causing your lack of rest. But know this much: getting better sleep is key to living a full, healthy life. Read up on how to get a better night sleep while you contemplate purchasing your new bed.