1: Sleep is a vital biological need for physical, mental, and emotional balance. Although most people focus on getting between 6 and 8 hours of sleep daily—as recommended by health specialists—the truth is that our sleeping position also has a significant impact on overall well-being. Sleeping on the right side, in particular, has been associated with certain negative effects that are worth being aware of.

2: Less efficient lymphatic drainage
The lymphatic system performs a key function: removing toxins, cellular waste, and excess fluid from the body. This system flows primarily to the left side of the body, where it empties into the thoracic duct, which drains into the left subclavian vein. Sleeping habitually on your right side can interfere with this process, hindering lymphatic drainage and promoting fluid accumulation or edema, especially in people with circulatory or lymphatic problems.

Increased Pressure on the Heart
Anatomically, the heart is slightly tilted toward the left side of the chest. Sleeping on the right side can put additional pressure on the heart, which in some people—especially those with pre-existing heart disease—can result in palpitations, discomfort, or difficulty resting soundly. Although it doesn’t pose a direct risk to healthy people, it can affect sleep quality and heart rate throughout the night.

3: Digestive Problems and Gastric Reflux
One of the most notable disadvantages of sleeping on your right side is its association with gastroesophageal reflux disease. This position facilitates stomach acids returning to the esophagus, due to the shape and orientation of the stomach. In contrast, sleeping on your left side facilitates intestinal transit and helps keep acids in the stomach thanks to gravity. For this reason, those who suffer from heartburn or hiatal hernia often experience greater relief when adopting the left position.

4: Which position is best?
Studies suggest that sleeping on your left side can benefit your digestive, lymphatic, and cardiovascular systems. This position also improves circulation, especially during pregnancy, and promotes the elimination of toxins while you sleep.

In conclusion, while sleeping on your right side isn’t necessarily harmful for everyone, adopting the habit of sleeping on your left side can offer significant long-term health benefits.