"Good posture is about maintaining the natural curves of your spine, whether you’re asleep or awake,” explains physiotherapist Stephanie Aickin, co-founder of Sheen Physiotherapy. “Sleeping on your side or your back is the easiest way to do this. Placing a pillow between the knees when you’re side-sleeping helps align the body and can be especially helpful if you have knee or hip pain. You shouldn’t aim to stay in one ‘perfect’ position all night, however. It’s normal and healthy to move around during the night, and it avoids excessive pressure.” However, since good sleep is crucial to your wellbeing, the best position is the one that allows you to get the most restful night’s rest, notes osteopath Anisha Joshi, author of Heal Your Back. “Find a position that allows you to sleep deeply and comfortably, as this outweighs any concerns over postures. This is especially important if you suffer from back problems, as poor sleep can decrease your body’s pain threshold.*”

Sleeping on your tummy can be a strain on your posture, says Aickin. “You have to twist your neck to the side, and your lower back is hollowed out, which can become stiff and uncomfortable. However, stomach sleeping feels comforting for some people, so it can be a very hard habit to break.” A firmer mattress might offer better support, and there are also simple ways to adjust your sleeping position to ease any strain. “Try doing a quarter turn of your body, putting one knee up, then sliding the opposite arm under the pillow, so your neck isn’t in such a twisted position,” suggests Aickin. If laying flat on your tummy is non-negotiable, “use a thinner pillow to reduce neck strain,” says Joshi. “And placing a pillow under your pelvis can help if you feel pressure on your lower back.”

Try matching your pillow to your sleeping style. “For side sleepers, a firmer, higher pillow may make them feel like their head is better supported, especially those with broader shoulders,” says Joshi. “Back sleepers may benefit from a softer medium-loft pillow that fills the gap between the neck and mattress.” Something too firm can raise the head too much, leading to neck discomfort. Ultimately, though, everyone is unique, notes Joshi. “For the best sleep possible, choose what feels most comfortable to you.” A good range includes options, from shape-moulding memory foam to cloud-like goose down, to suit all tastes.

What makes a mattress feel less than perfect can be influenced by body size and sleeping position. “A firmer mattress might feel good to back sleepers, especially heavier people, but cause discomfort on pressure points to side sleepers,” says Joshi. “However, it’s all subjective, and what is most comfortable for you may not be comfortable to your partner.” So, listen to your body. “Whether you like a firm or soft mattress, it should offer consistent support across the whole surface,” says Aickin. “If a mattress is sagging and old, it throws the body out of alignment and can even cause disc bulges.” While a mattress topper can’t remedy that problem, it can help when a bed just isn’t to your personal taste. “Putting a topper on a mattress that’s too hard for you will increase comfort, which can, in turn, improve sleep quality. This can be especially useful in rented accommodation, when you don't always have the option to choose your own bed.”

The benefits are well-proven, both in terms of better sleep quality and improved mental health. A study from 2022** found reported less severe insomnia, less fatigue and falling asleep more quickly, as well as greater life and relationship satisfaction and reduced anxiety and stress. “The negatives tend to be physical,” says Aickin, “snoring, movement and sleeping with another warm body. I’m an enthusiast of the Scandinavian strategy of having two single duvets on one bed. Not only does it mean that you can have your personal preference, you’re much less likely to disturb the other person by wriggling around during the night.”

This very much depends on your sleep environment, and what feels comfortable to you throughout the night, says Aickin. ‘There are no hard and fast rules. If you notice yourself feeling too hot or cold, change your tog. You could also have an extra throw handy that you can take on or off – it’s better than having to turn up the heating during the night.” Look for duvets which allow you to attach different togs together, for customisable year-round comfort.

Pets are family to many of us, and where they sleep may be non-negotiable. “However, I would almost always say keep animals out of the bedroom,” says Aickin. “That’s because they tend to have much shorter sleep cycles than humans, so they move around more, and there’s a very high chance of having your sleep disrupted. A lot of us are slightly allergic to animal hair, without even realising it, too.” That said, it can be therapeutic for some people. “If having them near makes you feel safe, that’s going to create a better frame of mind for sleep,” she adds. You could also consider creating a special area in the bedroom that’s just for your pets. That way, you and they can both benefit from being close by each other, while still getting uninterrupted sleep.

Lynne Hyland is a health and beauty journalist, and Beauty Director at “Good Housekeeping”.

https://pubmed.ncbi.nlm.nih.gov/22547894/

0010 Bed Sharing Versus Sleeping Alone Associated with Sleep Health and Mental Health | SLEEP | Oxford Academic