The American Heart Association also notes that sleep apnea is often considerably worse when people sleep on their backs rather than their sides.
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However, this does not mean that sleeping on the left side is necessarily better than sleeping on the right side for everyone with sleep apnea.
The evidence supporting left-side sleeping is particularly strong in the context of nighttime acid reflux.
For breathing-related conditions, the distinction between side sleeping and back sleeping is often more important than the distinction between the two sides.
Can changing sleeping position cure sleep apnea?
No.
This is an important point because some online articles suggest that changing sleeping positions can eliminate sleep apnea.
Positional adjustments may help people whose breathing problems are strongly influenced by their sleeping posture.
However, sleep apnea can also be caused by anatomical features, excess tissue around the airway, and other medical factors.
Some people continue experiencing breathing interruptions even when sleeping on their sides.
A sleep specialist may recommend a sleep study to determine the severity and characteristics of the condition.
Depending on the diagnosis, treatment may include continuous positive airway pressure therapy, oral appliances, positional therapy, or other medical interventions.
A sleeping position should not replace prescribed treatment.
The relationship between sleep quality and daytime energy
Poor-quality sleep can affect almost every aspect of daily life.
Someone who experiences repeated breathing interruptions may spend sufficient time in bed but still wake feeling exhausted.
During the day, they may struggle to concentrate, feel unusually irritable, or become sleepy during activities.
Long-term untreated obstructive sleep apnea is associated with cardiovascular complications, including high blood pressure and increased cardiovascular risk.
This is why persistent snoring accompanied by breathing pauses should not be dismissed as an ordinary sleeping habit.
Choosing a comfortable side-sleeping position
For people who have been advised to try side sleeping, a few adjustments can improve comfort.
First, use a pillow that keeps the head and neck aligned with the spine.
A pillow that is too high can push the head upward, while one that is too flat may allow the neck to bend downward.
Second, consider placing a pillow between the knees.
This may help reduce pressure around the hips and lower back.
Third, avoid curling the body excessively into a tight fetal position if this causes discomfort.
A naturally bent posture is generally more comfortable for many people.
Finally, make sure the mattress provides adequate support.
A mattress that is excessively soft may allow the shoulders and hips to sink too deeply, while an overly firm surface may create uncomfortable pressure points.
The objective is to support the body without creating unnecessary tension.
Chapter 4: What About the Heart and Pregnancy? Is the Right Side Really Harmful?
One of the most confusing aspects of online sleeping-position advice is the number of claims about the heart and circulation.
Some articles suggest that sleeping on the right side puts pressure on the heart.
Others claim that everyone should sleep exclusively on the left side to improve blood circulation.
These statements are too simplistic.
Medical research suggests that sleeping position can matter in certain cardiovascular conditions, but there is no universal rule that the right side is dangerous for a healthy person.
Understanding sleeping positions and heart health
The heart sits inside the chest, slightly toward the left side, between the lungs.
Its position sometimes leads people to assume that sleeping on the left must place harmful pressure on it.
However, the body is designed to protect and support its internal organs.
Simply lying on the left or right side does not normally damage a healthy heart.
In fact, sleeping preferences may differ among people with cardiovascular conditions.
Some individuals with heart failure experience shortness of breath when lying on their left sides and may find the right side more comfortable.
This is one reason medical professionals consider individual symptoms rather than recommending one sleeping position for everyone.
The American Heart Association emphasizes that the relationship between sleeping position and heart health is more complicated than many online headlines suggest.
American Heart Association
Why some heart patients prefer the right side
People living with heart failure may experience difficulty breathing when lying flat.
This can happen because fluid accumulation and changes in circulation affect the lungs and respiratory system.
Some patients find that a particular side makes breathing easier.
For them, comfort and the ability to breathe normally are important considerations.
A person who feels breathless or experiences chest discomfort when lying on one side should discuss these symptoms with a healthcare professional.
New or severe chest pain, particularly when accompanied by sweating, dizziness, or shortness of breath, requires emergency assessment.
It should never automatically be attributed to sleeping position.
What pregnant women should know
Pregnancy is another situation in which sleeping position receives considerable attention.
As pregnancy progresses, the uterus becomes larger and heavier.
Lying flat on the back during later pregnancy can place pressure on major blood vessels, potentially affecting circulation and causing discomfort.
For this reason, pregnant individuals are commonly advised to sleep on their sides during the second and third trimesters.
However, an important distinction is necessary.
Sleeping on the right side is not automatically unsafe during pregnancy.
An NIH-funded study published in 2019 examined more than 8,700 pregnancies and found no increased risk of adverse pregnancy outcomes associated with sleeping on the right side or back through the 30th week of pregnancy.
The researchers emphasized that their findings did not establish the safety of every position during the final weeks of pregnancy.
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Current pregnancy guidance generally emphasizes going to sleep on either side rather than insisting that every pregnant person must remain exclusively on the left.
The American College of Obstetricians and Gynecologists also recommends side sleeping during the second and third trimesters, with pillows used to improve comfort and support.