Daylight saving time ends this weekend, and doctors say the sudden shift can do more than make it dark earlier — it can throw off sleep, mood and energy for days afterward.
Dr. John La Puma, a California physician who specializes in nature-based medicine, says the problem is that the body’s internal clock doesn’t reset the moment the clock on the wall does.
“When the clocks change, your body clock is still on the old time,” La Puma said. “So, for about a week, you wake up an hour early. You get hungry early. You feel sleepy early. It gets dark by five. Afternoon light goes away. You get months of short days. … You need coffee just to feel human. It’s not great.”
Some research has pointed to cardiovascular benefits from the fall time change, but the earlier loss of evening sunlight can suppress serotonin and melatonin production, which may contribute to a depressed mood, La Puma said.
Ease Into It Before the Clocks Change
Clocks fall back overnight Saturday. La Puma recommends starting the adjustment early, nudging bedtime, meals and wake-up times later in small steps starting Friday.
“So, you move your day later in small steps,” he said. “You move your bedtime and meals the same 15 minutes each time.”
For someone who usually turns in at 10 p.m., that could mean 10:15 p.m. Friday and 10:30 p.m. Saturday, with meals and wake-up times shifting by the same small amounts as schedules allow.
Watch the Halloween Combination
Because the time change falls on Halloween this year, Dr. Saema Tahir, a sleep medicine doctor in New York City, warned against treating the extra hour as license to stay out late and drink more than usual.
“Keep alcohol moderate, finish drinking a few hours before bed and avoid caffeine after early afternoon,” Tahir said. “Alcohol makes you drowsy at first but breaks up sleep in the second half of the night. Caffeine stays in your system for hours. Together, they can leave you more tired on Sunday than you would be with no time change at all.”
Get Outside at the Right Times
Both doctors emphasized the value of deliberate sunlight exposure. La Puma suggests getting outdoors each afternoon, later in the day, since afternoon light sends a different signal to the body than morning light.
“You want to get outside at the right minutes, at the time of day and in the right place if you can,” he said. “Late-day daylight is different than morning daylight. Late-day daylight tells your body the day is running long, and it shifts later.”
Once the adjustment period has passed, Tahir recommends getting outdoor light within an hour of waking every day through the winter months.
“Light is the strongest signal the body clock gets,” Tahir said. “Evening light pushes it later, which is the direction you need to go for ‘fall back.’ Morning light keeps it stable over the darker months and supports mood and daytime alertness.”
Build a Wind-Down Routine
La Puma recommends choosing a calming bedtime ritual — writing in a paper notebook, sipping chamomile tea, taking a bath or using aromatherapy — to signal to the body that sleep is coming. He outlines these ideas in his book, “Indoor Epidemic.”
“Very specific things that tell your brain and body, ‘I’m winding down so I can go to sleep.'”
He also advises cutting off caffeine after noon and stopping screen use at least an hour before bed, since screen light can suppress melatonin even when night mode is turned on.
Keep a Consistent Wake-Up Time
Once the clocks have changed, La Puma stressed sticking to one wake-up time every day, including weekends.
“Pick one wake-up time and keep it every day, weekdays and weekends.”
He pointed to an eight-year study of roughly 60,000 people that linked consistent sleep and wake times to a 19% lower risk of death.
“So, sleep and wake times have important effects on heart attack, stroke and cardiovascular mortality,” La Puma said.
The National Institutes of Health advises anyone with persistent trouble falling or staying asleep, frequent daytime fatigue, or sleep loss that interferes with daily life to contact a healthcare provider.
