The heart is the Superman of organs: it pumps oxygen and nutrients to the rest of our (very needy albeit grateful) bodies; it also takes care of the ‘bad guys’ by carrying away waste. But if the heart is the hero giving out blood and valiantly ridding our bodies of things like carbon dioxide, then what is the Lex Luthor? Legions of notorious ‘heart enemies’ already exist (cheeseburgers, anybody?), but a recent study published in the journal Hypertension, proposes a new villain: restricted and disrupted sleep.
According to the study, the heart — just like the brain — needs stable and restorative sleep every night in order to rejuvenate properly. Thus, people who repeatedly don’t get enough sleep and have unstable sleeping patterns could be increasing their risk of heart disease.
Researchers have known this to be true for sometimes — it’s well-documented that shift workers or others who have poor sleep patterns are more likely to suffer from cardiovascular problems. Yet, the reasons why insufficient sleep and circadian rhythm (a.k.a. ‘body clock’) disturbances are associated with heart problems have eluded those in the scientific community for years.
In the search for evidence, researchers at Northwestern University recruited 26 healthy people between the ages of 20 and 39. The participants’ sleep routines were restricted so that they all only slept for five hours each night for eight days. Additionally, some of the subjects bedtimes were delayed for by 8.5 hours for half of those days, while the other subjects had fixed sleep routines that fit into normal circadian rhythms.
Their findings showed that restricted sleep led to an increased heart rate in both those who had their bedtimes delayed and those who didn’t — although those who went to bed later for those four days saw an even greater rise in heart rate. They also noted that there was reduced activity for the vagal nerve, which normally controls the process of slowing people’s heart beat when they enter deep sleep.
Furthermore, measurements of the subjects’ urine revealed an increase in excretion of the stress hormone, norepinephrine — a powerful little hormone that can increase blood pressure, expand the windpipe, and narrow blood vessels — all things that are not ideal for the heart in the long-term.
So how can you step up and prevent your most heroic organ from getting into trouble? As the study suggests, you can adopt a regular bedtime routine (if your work allows it, that is). As well, heed the National Sleep Foundation’s recommendations on how many hours you need each day of sleep and follow your body’s natural circadian rhythms.
You owe it to the prince of Krypton, after all.