Buzz
I’m someone who tosses and turns endlessly before finding the perfect sleeping position, often cycling through all options multiple times. During my pregnancy, I was repeatedly told that sleeping on the left side is ideal. However, studies indicate that the right side might be more beneficial for individuals with specific health concerns. Let’s dive into the details to figure out the best side for you.
What are the pros and cons of side sleeping?
If your current sleeping posture feels comfortable and no medical conditions require a change, there’s no need to alter your habits.
Side-sleeping is frequently recommended as a beneficial practice. For pregnant individuals, sleeping on the stomach becomes impractical. Back sleeping during pregnancy can restrict blood flow, as major blood vessels like the aorta and vena cava are located along the back of the abdominal cavity. As the uterus expands, it may exert pressure on these vessels.
Those with obstructive sleep apnea are often advised against back sleeping, as it can increase apneic episodes. Back sleeping is also known to exacerbate snoring. (Note: If you haven’t been tested for sleep apnea but notice improved sleep when avoiding your back, consider seeking a test.)
For individuals dealing with back pain, side-sleeping is typically more comfortable than back or stomach sleeping—though preferences vary.
Benefits of Sleeping on Your Left Side
The primary advantage of left-side sleeping relates to the stomach’s anatomy. Contrary to the common misconception of the stomach as a round ball, it’s actually smaller and asymmetrical. The esophagus connects to it on the right side. (Refer to this diagram from the University of Rochester Medical Center for a detailed illustration of its shape and location.)
Due to this anatomical structure, lying on your left side helps keep food and digestive fluids in the stomach, where they belong. For those with GERD or frequent heartburn, sleeping on the right side may increase the likelihood of stomach acid entering the esophagus, worsening symptoms.
(Interestingly, while most people have their organs arranged as described, some individuals have a mirrored organ placement, a rare condition. According to a review in the International Journal of Internal Medicine, this anomaly is so uncommon that even experienced surgeons might encounter it only once or twice in their careers.)
Reasons to Consider Sleeping on Your Right Side
While left-side sleeping benefits the stomach, it slightly alters the heart’s position. The heart sits slightly left of the chest’s center, supported by the mediastinum, a connective tissue structure in the middle of the chest.
Right-side sleeping stabilizes the heart within the mediastinum. In contrast, left-side sleeping causes the heart to sag and rotate slightly. While this is generally harmless, the movement is detectable through electrocardiogram readings.
As a result, it’s believed that the heart functions more efficiently when lying on the right side compared to the left. This could enhance breathing for those with sleep apnea. Additionally, animal studies suggest that side sleeping may boost the brain’s ability to clear “glymphatic” waste—a crucial maintenance process during sleep.
What to Do If These Factors Don’t Apply to You
If your doctor has recommended a specific sleeping position, follow their guidance. However, if their suggestion feels uncomfortable or impractical, inquire about the reason behind it and how critical it is. The recommendation might simply aim to improve comfort rather than address a medical necessity. Clarifying this can help you make an informed decision.
For others, experimenting with different sleeping positions is generally safe. While anatomical factors like heart and stomach shape may favor one side, our bodies are complex. For instance, if an old shoulder injury flares up when sleeping on that side, it’s wise to avoid that position.
In most cases, outside of specific medical conditions, the best sleeping position is the one that feels most comfortable. The Sleep Foundation emphasizes that the ideal side depends on personal preference and the quality of your mattress and pillow. Their advice? “If discomfort or pain arises, switch to a different position.”
