Korva is a scroll of the internet’s best ideas.
One lost hour, 24% more heart attacks
Daylight saving time works as a global experiment on 1.6 billion people across 70 countries, performed twice a year. Many people think nothing of losing an hour of sleep, yet the cardiovascular system responds to it within days.
The body shows this fragility to even the smallest perturbations of sleep. After one week of short sleep, blood sugar levels are disrupted so significantly that a doctor would classify a person as pre-diabetic.
The heart attack figures run in both directions. The spring change takes an hour away and heart attacks climb. The fall change hands an hour back and they fall.
How did daylight saving time begin?
Germany introduced it in 1916, in the middle of World War I, as a way to save coal used for lighting. Britain and many other countries followed within weeks. The United States adopted it in 1918, repealed it, and then left it to local choice until the Uniform Time Act of 1966. The idea had been floated earlier by the New Zealand entomologist George Hudson and the British builder William Willett.
How does short sleep disrupt blood sugar?
Sleep loss lowers the body's response to insulin, the hormone that moves sugar out of the blood. In a 1999 study in The Lancet, Eve Van Cauter and colleagues at the University of Chicago limited healthy young men to four hours of sleep for six nights. Their glucose tolerance fell to levels typical of prediabetes. The men's insulin response to a sugar load was also weaker.
Why would losing sleep strain the heart?
Sleep is when blood pressure and heart rate normally dip. Less sleep keeps the sympathetic nervous system, the body's stress-response circuit, more active through the day. It is also tied to higher levels of inflammatory markers in the blood. Chronically high blood pressure and inflammation are both established contributors to heart disease.
More from Talks at Google
