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Sleeping on Left side Bad for Heart?



I saw an article on line concerning sleeping on ones left side being bad for the heart. The article was on WEB MD webpage talked about this. Do you have any information on this? It seems a very strange idea.


This is an interesting question about the effects of body position on heart function. I assume you are talking about adults and not children and will address this specifically.

It has been shown that patients with chronic heart failure tend to prefer sleeping on their right side as opposed to their left. Subsequent studies have demonstrated that, indeed, sympathetic nervous system activity is lower in patients with chronic heart failure, or in those who have had a heart attack, when they lie on their right sides versus their left. Sympathetic nervous activity is what controls heart rate and blood pressure and thus, for these patients, lying on the right reduces their heart rate and blood pressure, both of which are good for the heart when faced with these medical conditions. As such, some authorities recommend that patients with heart failure or who have had a heart attack not sleep on their left sides. It should be noted, however, that this therapy has not been studied to confirm that it changes other clinical outcomes.

Why lowering of sympathetic nervous system activity happens with changes in position is not entirely clear. Some researchers have suggested that when the right side is down, the heart is in a more superior position, making it easier for it to pump blood out. However, this has not been studied at this time to prove this is the case. Furthermore, whether the effects noted are of any significance to individuals who do not have heart failure or have not had a heart attack is unclear.

Of interest, body position in sleep does affect other conditions. For those with heart burn (gastroesophageal reflux), sleeping with the right side down actually worsens nighttime reflux as compared to sleeping with the left side down. And for those with obstructive sleep apnea, sleeping flat on your back tends to worsen this condition (as opposed to sleeping on your sides).

If you have other specific questions about sleep or other sleep disorders, please visit the American Academy of Sleep Medicine website. In addition to information, the website contains a list of Sleep Centers and Sleep Specialists across the country so that you may locate one near you. The website Sleep also contains plenty of consumer friendly information about sleep and sleep apnea. Good luck and here’s to better sleep!

For more information:

Go to the Sleep Disorders health topic.