内容摘要：that has whipsawed Nvidia and other Big Tech companies riding AI mania to propel their revenue and stock prices upward.

that has whipsawed Nvidia and other Big Tech companies riding AI mania to propel their revenue and stock prices upward.

Morning light resets the rhythm. By evening, levels of a hormone called melatonin begin to surge, triggering drowsiness. Too much light in the evening — that extra hour from daylight saving time — delays that surge and the cycle gets out of sync.Sleep deprivation is linked to heart disease, cognitive decline, obesity and numerous other problems. And that circadian clock affects more than sleep, also influencing things like heart rate, blood pressure, stress hormones and metabolism.

Fatal car crashes temporarily jump the first few days after the spring time change, according to a study of U.S. traffic fatalities. The risk was highest in the morning, and researchers attributed it to sleep deprivation.Then there’s the cardiac connection. The American Heart Association points to studies that suggest an uptick in heart attacks on the Monday after daylight saving time begins, and in strokes for two days afterward.Doctors already know that heart attacks, especially severe ones, are a bit more common on Mondays generally — and in the morning, when blood is more clot-prone.

Researchers don’t know why the time change would add to that Monday connection but it’s possible the abrupt circadian disruption exacerbates factors such as high blood pressure in people already at risk.Gradually shift bedtimes about 15 or 20 minutes earlier for several nights before the time change, and rise earlier the next morning, too. Go outside for early morning sunshine that first week of daylight saving time, another way to help reset your body’s internal clock. Moving up daily routines, like dinner time or when you exercise, also may help cue your body to start adapting, sleep experts advise.

Afternoon naps and caffeine as well as evening light from phones and other electronic devices can make adjusting to an earlier bedtime even harder.

Every year there’s talk about ending the time change. In December, then-President-elect Donald Trump promisedRaramuri Indigenous woman Gloria Vega, right, watches a neighbor wash clothes outside her home in Cuauhtemoc, Mexico, Thursday, May 1, 2025. (AP Photo/Martin Silva Rey)

Raramuri Indigenous woman Gloria Vega, right, watches a neighbor wash clothes outside her home in Cuauhtemoc, Mexico, Thursday, May 1, 2025. (AP Photo/Martin Silva Rey)But the forced leave and docked pay left her reeling. She said she’s living paycheck to paycheck and wonders how she’ll pay the bills — her daughter’s school supplies, lunches, tennis shoes.

“I have a daughter to keep afloat,” she said. “It’s not like I have the option to wait and pay for things, for food.”Associated Press videojournalist Martín Silva Rey contributed to this report from Cuauhtemoc, Mexico.