Sunday’s start of daylight saving time will throw off the clock only by an hour, but that’s enough to leave people feeling groggy for a day or two, sleep experts say.

By setting clocks ahead an hour, daylight saving time allows us more light through the spring, summer and fall. But when the time changes at 2 a.m. Sunday (except in Arizona and Hawaii), it will cost one hour of sleep. We’ll regain that when the clocks fall back on Nov. 4.

“Losing an hour is harder than gaining an hour,” says Steven Feinsilver, director of the Center for Sleep Medicine at Mount Sinai Medical Center in New York. “It’s sort of like a mini jet lag.”

It takes no more than 48 hours to adjust to a one-hour loss, says New York pulmonologist and sleep specialist Nicholas Rummo of Northern Westchester Hospital’s Center for Sleep Medicine. “The day or two after people aren’t quite alert,” he says. “Most people might feel it Monday into Tuesday.”

Some people will be more sluggish than others Monday morning — particularly those without regular sleep habits, such as waking up at a consistent time or snoozing seven to eight hours each night.

“Millions of Americans can ill afford to lose one more hour of sleep given that so many of them are so sleep-deprived,” says Russell Rosenberg, board chairman for the National Sleep Foundation.

Sleep directly affects health and safety, Rosenberg says, and the sleep loss associated with daylight saving time has been linked to increases in traffic and on-the-job accidents the Monday following the time change.

Specialists encourage people to use this, the National Sleep Foundation’s National Sleep Awareness week, to adopt good habits so that next year, it won’t be quite so tiring to make the leap forward. Sleep doctors offer a few tips for making up for lost z’s:

•Start early. Move your schedule up a few minutes each day — eat dinner and go to bed 10 to 15 minutes earlier every night.

•Take a nap Sunday to “build up a little sleep in your sleep bank,” says Russell Rosenberg, board chairman for the National Sleep Foundation, noting that siestas should be less than an hour.

•Every minute counts, so set the alarm clock for the last possible minute Monday morning.

•Soak up the sun. Sunlight jump-starts our bodies and sets our internal clocks forward, so sip your coffee in front of a window for an extra jolt. “Light in the morning makes us want to go to bed earlier,” says New York pulmonologist and sleep specialist Nicholas Rummo.

•Avoid alcohol and caffeine, which interfere with the hormones and chemistry that regulate our bodies and make it more difficult to fall asleep and wake up, Rummo says.