Do You Sleep on Your Left or Right Side? Learn How Does This Affects Your Heart & Liver Functions

The position you choose to sleep in every night does more than just affect the quality of your sleep—it can also influence your overall health, including digestive and heart function. While the benefits and risks of different sleeping positions have become a topic of study over the years, researchers continue to provide fascinating insights into how left-side and right-side sleeping might uniquely affect us.

The Case for Sleeping on Your Left Side

For individuals dealing with digestive conditions, such as acid reflux or gastroesophageal reflux disease (GERD), sleeping on the left side may be highly beneficial. A 2022 study published demonstrated that sleeping on the left side significantly reduced acid exposure in the esophagus while also facilitating faster esophageal clearance.

When compared to sleeping on the right side, these findings highlight the remarkable effects of left-side sleeping on digestion. However, while promising, the effects of deciding to sleep in this position could extend far beyond the digestive system.

Interestingly, some research also explored possible links between left-side sleeping and the heart. Back in 1997, researchers first identified measurable changes in the electrical activity of the heart when individuals slept on their left side.

Using electrocardiograms (ECGs), they noticed distinctive shifts that seemed more pronounced when participants were in this position. Decades later, in 2018, another study used advanced imaging techniques, such as vectorcardiography, to investigate this further.

The findings showed that left-side sleeping physically caused the heart to shift and turn—an intriguing phenomenon that added another layer to how sleeping positions could interact with the cardiovascular system.

However, before sounding alarms, it’s worth clarifying what these shifts mean. Researchers explained that the changes observed were not due to any dysfunction in the heart’s electrical function. Instead, these changes were attributed to the shift in heart positioning caused by sleeping on the left side, rather than any direct issues with the heart’s rhythm or operation.

This shift made it easier for ECG readings to capture altered signals. What does this mean in terms of risk? Right now, experts argue that there’s no evidence that left-side sleeping inherently compromises heart health, though additional studies are needed when considering individuals with pre-existing cardiovascular conditions.

Weighing the Concerns About Sleeping on Your Left Side

Even though research outcomes are largely neutral when it comes to left-side sleeping and heart health, there’s still some debate about whether this position could produce negative effects in specific circumstances.

Notably, the ongoing conversation centers on whether some individuals, particularly those with sensitive heart conditions, might need professional guidance regarding their sleep posture. At present, experts urge caution rather than alarm, with researchers emphasizing the need for further investigation.

Why Right-Side Sleeping May Be the Safer Choice for the Heart

While the debate about left-side sleeping remains open, right-side sleeping may provide some benefits, particularly for those managing heart failure or related conditions. Previous studies indicate that sleeping on the right side promotes greater heart stability.

For starters, a 2018 study found that participants with dilated cardiomyopathy—a heart muscle disease that affects its ability to pump blood effectively—often showed a preference for sleeping on their right side.

Physiologically speaking, one critical advantage of right-side sleeping is that it appears to hold the heart in place securely, thanks to the stabilizing role of the mediastinum. This thin tissue layer between the lungs helps support the heart, preventing it from shifting as much as it would otherwise. It keeps cardiac activity steady and minimizes unnecessary movement.

Pregnant individuals are also frequently advised to adjust their sleep positions according to what’s safest for their health and their baby. According to a 2019 review, pregnancy-safe sleeping includes either side—left or right—with no significant health difference noted between the two.

Nonetheless, left-side sleeping is typically encouraged during pregnancy to reduce pressure on the liver, which is located on the upper right side of the abdomen. For those who find left-side sleeping uncomfortable, right-side postures might make it easier for the heart to balance the weight of the growing uterus, optimizing blood flow back to the fetus through the inferior vena cava.

Navigating Sleep Positions After Heart Failure

A significant takeaway for heart failure patients is prioritizing comfort and personalized advice for sleep positioning. Most importantly, consulting with a healthcare professional should guide any adjustments needed. Anecdotal reports suggest that many heart failure patients favor sleeping on their right side over their left side, potentially due to the reduced pressure on the heart.

For those without significant breathing issues like sleep apnea, sleeping on the back can be another consideration. But individuals with obstructive sleep apnea, untreated symptoms, or significant fluid retention after medical procedures should explore alternatives—they may find sleeping upright on a recliner or with wedge support particularly helpful.

If an implantable cardioverter defibrillator (ICD) is in place, selecting the side opposite its implantation site can often enhance overall comfort and reduce disturbances during rest.

Does Sleeping on Your Stomach Play a Role?

Stomach-sleeping is sometimes thought to reduce snoring and ease mild cases of sleep apnea for certain individuals. However, it does come with its downsides. Sleeping on the stomach can strain the neck and back, leading to discomfort in the long term. Since sleep apnea and heart failure are often interconnected, addressing one can significantly improve outcomes for the other. That said, proper management of each condition is essential.

The Importance of Prioritizing Quality Sleep

While sleeping positions may invite scientific curiosity, the true focus for heart and overall health lies in ensuring adequate, restorative sleep. Whether you favor left-side, right-side, or back positions, poor sleep quality disproportionately increases your risk of developing heart disease and other chronic illnesses over time.

For heart failure patients, poor sleep often exacerbates symptoms like fatigue, shortness of breath, or water retention. Anecdotally, they report feeling better when they settle into sleep positions that work for both comfort and breathing ease.

Final Thoughts on Choosing a Sleep Position

At this point, there’s no consensus in the scientific community about the best sleeping position for optimal heart health. Finding what works for your unique set of needs—whether left-side sleeping for digestion or right-side resting for heart support—may involve some experimentation.

Regardless of your chosen posture, prioritizing restful, high-quality sleep should remain the ultimate goal in optimizing your well-being. For unanswered questions or concerns, speaking with a trusted healthcare provider is always advisable. Remember, the key to successful sleep isn’t just positioning—it’s the total quality of each night’s rest that truly matters.