Daylight saving time starts this weekend and ends ... well, maybe never.

The twice-yearly clock-resetting ritual — a major annoyance for many people and a health concern for others — could be on its way out as lawmakers increasingly agree that we should ditch the practice. Three measures are pending in Congress that would do just that, and while similar bills have struggled in the past, some observers are predicting that this is the year things will change.

But change to what — year-round DST or 12 months of standard time — is the subject of much debate.

The time switch, especially in the spring, has been blamed for increases in heart attacks and traffic accidents as people adjust to a temporary sleep deficit. There's also the inconvenience factor, with folks oversleeping because they forget to reset alarm clocks or having to search for owner's manuals to remind themselves how to change the clocks in their cars.

At last count, 71% of people want to stop springing forward and falling back, according to a 2019 Associated Press-NORC Center for Public Affairs Research poll. Politicians have reacted accordingly. More than 200 state bills have been filed since 2015 to stop the practice, according to the National Conference of State Legislatures.

But there are some strong opinions about which time should become permanent.

Retailers, chambers of commerce and recreational industries historically have favored DST and the sunny evenings that allow more time to shop and play.

But researchers of human biological rhythms come down squarely on the side of the standard, wintertime hours. They're worried that a lack of sunlight in the morning — especially in December and January when an already late sunrise would come an hour later under daylight time — would have a negative effect on both mental and physical health.

The measures getting the most traction right now are for permanent daylight saving time, which makes more sun available for after-work activities. In 2018, Florida passed a bill and California voters backed a ballot measure to do so. Maine, Delaware, Tennessee, Oregon and Washington joined in 2019, passing permanent daylight saving bills.

But none of those efforts can become reality without the blessing of Congress. States always have been able to opt out of summer hours and adopt standard time permanently, as Arizona and Hawaii have done. But making daylight saving time year-round is another story.

Is this the year?

Scott Yates, whose Lock the Clock website has become a resource for lawmakers pushing for change, believes we're getting close to settling the matter.

Yates, 54, a tech startup CEO based in Denver, has been promoting an end to clock-switching for six years. He doesn't pick a side. It's the switching itself that he wants to end. At first, it was just about the annoyance, he said. But then he began to see scientific studies that showed the changes were doing harm.

A German study from 2006 to 2015 showed a significant uptick just after the spring switch in deaths caused by cardiac disease, traffic accidents and suicides. Researchers also have noted an increased risk for heart attacks and strokes.

Lawmakers in several states are preparing resolutions and bills, some of which would be triggered by congressional approval and the adoption of daylight time in surrounding states.

The Illinois Senate passed such a bill, and Kansas is considering one. In Utah, state Rep. Ray Ward, a physician, is steering a recently passed state Senate permanent daylight bill through the House.

"The human clock was not built to jump back and forth. That's why we get jet lag," said Ward. "It is very easy to show that if you knock people off an hour of sleep there's a bump temporarily in bad things that will happen."

Efforts have been particularly strong in California, where 60% of voters passed a ballot issue for permanent daylight time in 2018. A bill is pending in the state Assembly.

An opposing view

The drive to embrace year-round DST alarms scientists who study human biological rhythms.

The Society for Research on Biological Rhythms posts its opposition prominently at the top of its website. Messing with the body's relationship to the sun can negatively affect not only sleep but also cardiac function, weight and cancer risk, the society warns.

According to one often-quoted study on different health outcomes within the same time zones, each 20 minutes of later sunrise corresponded to an increase in certain cancers by 4 to 12%.

"Believe it or not, having light in the morning actually not only makes you feel more alert but helps you go to bed at the right time at night," said Dr. Beth Malow, director of the sleep division of Vanderbilt University School of Medicine.

Jay Pea, a freelance software engineer in San Francisco, was unhappy enough about California's proposed permanent daylight time that he started the Save Standard Time website to promote the health arguments for keeping it permanent. He said he doesn't think the scientific community is being heard.

"It's bizarre to me that politicians are not hearing the experts on this," he said.

At the very least, lawmakers ought to consider history, he said. In 1974, the federal government decided to temporarily make DST year-round as a way to deal with the energy crisis (although energy savings were later found to be underwhelming). Support for the move plummeted in the winter when the sun didn't rise until 8 a.m. or later and parents worried for the safety of kids waiting in the dark for school buses.

Pea attributes the push for permanent summer hours to the emotional attachment with summer.

"It's a shame that every generation we have to revisit this issue," he said.