Getting too little or too much sleep can harm your health - here's how
It's not just the amount of sleep that's important for cardiovascular health either.
ISLAMABAD (Online): Researchers say six to eight hours of sleep is the “sweet spot” for most people.
Researchers say poor sleep is a risk for health problems just like an unhealthy diet and inadequate exercise. Getty Images
Six to eight hours of sound sleep is the sweet spot for cardiovascular health. No more and especially no less.
That’s the conclusion of a new study showing that people who slept less than six hours were 27 percent more likely to have atherosclerosis throughout their body.
Women who slept more than eight hours nightly also were at increased risk of plaque buildup (or “hardening”) in the arteries.
It’s not just the amount of sleep that’s important for cardiovascular health either.
Researchers reported in the Journal of the American College of Cardiology that study subjects who reported poor quality of sleep were 34 percent more likely to have atherosclerosis than those who generally got a good night’s sleep.
Alcohol and caffeine use were higher among those who reported short or disrupted sleep, researchers also noted.
“It is almost common sense that it is better to have a few hours of good sleep than spend hours agitated by the impossibility of reaching a restful sleep,” said José M. Ordovás, PhD, a senior study author as well as a researcher at the Centro Nacional de Investigaciones Cardiovasculares Carlos III in Madrid and director of nutrition and genomics at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University.
The study is the first to show that objectively measured sleep is independently associated with atherosclerosis throughout the body, not just in the heart.
“It could be that at the early stages of the disease, the plaque development is happening faster in the periphery than in the heart,” Ordovás told Healthline. “The bottom line is that future studies should examine the multi-territory assessment of atherosclerosis to identify with more precision — and probably earlier — those individuals at risk.”
Seeking ‘precision sleep’
Past studies have found a link between lack of sleep and increases in risk factors for heart disease, including high blood glucose levels, high blood pressure, inflammation, and obesity.
Ordovás said his study found that short or poor sleep contributed to atherosclerosis even after controlling for other risk factors, “suggesting that additional, unmeasured mechanisms are acting to increase the risk due to lack of sleep.”
Six to eight hours of sleep “seems to be the proper amount of time to maintain the homeostasis of the circadian rhythm,” he said.
He also noted that in future research, “just like we talk about precision medicine or precision nutrition, we also want to achieve precision sleep.”
“One aspect that remains to be understood from this data is if sleep timing — when people sleep in relation to their circadian rhythm — might confer an additional associated increase in vascular disease risk,” Dr. Jeffrey Durmer, medical director of the Atlanta-based sleep health company FusionHealth, told Healthline.
“From multiple lines of human and animal circadian rhythm neurobiological research, one would suspect that the timing of sleep has just as much, if not more, impact on the vasculature as a reduced duration and/or quality of sleep.”
