A doctor has highlighted a simple "pillow rule" for people taking weight-loss medications such as Mounjaro and Wegovy who experience new discomfort at night. The advice comes as research suggests around 1.9 million adults in the UK have used GLP-1 medications, many for weight loss.
Weight loss can change how you sleep
Dr Roger Henderson, a GP with more than 40 years' experience and medical expert for MattressNextDay, says losing a significant amount of weight can alter how the body is supported during sleep. This can lead to new aches, pressure points and even changes to a person's usual sleeping position.
He said: "Losing weight, especially if it is a significant amount, changes how your body is supported while you sleep, so it can affect both your posture and your comfort. Many people find they're able to sleep more comfortably in positions they used to avoid."
"Reduced weight can ease the strain on the hips, knees and lower back, making movement in bed easier than before as well as reducing joint discomfort. At the same time, with less padding over bony areas, some people notice increased tenderness around the shoulders or hips until they adapt or make changes to their sleep set-up."
The pillow rule for side sleepers
For side sleepers, one simple adjustment could make a difference. Dr Henderson has what he calls a straightforward "pillow rule" for anyone noticing new hip or lower back discomfort.
He explained: "If you've lost weight and suddenly find sleeping on your side less comfortable around your hips, try placing a pillow between your knees. It sounds simple, but it stops your top leg falling forwards and rotating the pelvis, which can help keep your hips and spine in a more neutral position overnight."
"I'd also pay attention to your head pillow if you find yourself sleeping in a different position after losing weight. If you're now spending more time on your side, for example, you may need a slightly deeper pillow to fill the gap between your shoulder and head and prevent your neck dropping towards the mattress."
Side effects and when to see a GP
The NHS says medicines including semaglutide, sold as Wegovy and Ozempic, and tirzepatide, sold as Mounjaro, can cause side effects including nausea, indigestion and acid reflux, which may also affect sleep, particularly during the early stages of treatment. It advises people experiencing persistent or troublesome side effects to speak to the healthcare professional responsible for their care.
Dr Henderson also said people who lose a significant amount of weight may feel colder in bed, snore less or find their mattress suddenly feels firmer because body shape and weight distribution have changed. If sleep problems persist, or symptoms such as loud snoring, gasping for breath or excessive daytime tiredness continue, he recommends speaking to a GP.
