There are plenty of claims about the “best” sleep position – for example, it’s often thought that sleeping on your left side aids digestion.
This idea comes from basic anatomy: the stomach sits to the left, and its outlet (the pylorus) tilts slightly to the right, connecting to the small intestine.
There’s some evidence that left-side sleeping may reduce acid reflux compared to the right, as it positions the stomach in a way that makes acid less likely to creep up into the oesophagus.
If you suffer from reflux or heartburn, it certainly could be worth trying.
But digestion happens regardless of how you sleep. So, unless you have a specific digestive issue (like reflux), your position likely won’t make much difference.
Of course, sleep is about more than digestion. Back sleeping (supine) is often recommended to reduce pressure on the neck and lower back. However, it can worsen snoring or sleep apnoea by allowing the tongue to flop backwards, partially blocking the airway.
Side sleeping is the most common and can also help with snoring and sleep apnoea by keeping airways more open.
Pregnant women are often advised to sleep on their left side to improve blood flow to the baby and reduce pressure on the liver, but right-side sleeping is generally fine too.
If you have back or pelvic pain (especially if pregnant), side sleeping with a pillow between your knees, can also ease pressure on the lower back.
So, what’s really the best position to sleep in?
Ultimately, there’s no single optimal sleep position. Left-side sleeping might be helpful for reflux or pregnancy, but for most people, the priority should be comfort, spinal support and good-quality sleep – whichever position you can get that in.
And let’s be honest, no matter how carefully you position yourself at bedtime, you’ll probably wake up drooling into your pillow in some completely different pose anyway!
This article is an answer to the question (asked by Tim Hatley, Lincoln) 'What's the best position to sleep in?'
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