Daylight saving time negatively impacts healthy living, study finds

New research indicates that the transition to daylight saving time (DST) negatively impacts our healthy habits

New research indicates that the transition to daylight saving time (DST) negatively impacts our healthy habits. The onset of DST, when most U.S. jurisdictions "spring forward" by setting clocks ahead one hour, is associated with increased consumption of processed snacks and decreased visits to the gym.

“There’s quite a bit of research in health fields related to how well-being is affected by daylight saving time,” says Ram Janakiraman, corresponding author of the study and a professor of marketing analytics at North Carolina State University’s Poole College of Management. “We wanted to explore similar issues through the lens of consumer behavior, giving us new insights into how daylight saving influences the decisions we make.”

Rishika Rishika, co-author and associate professor of marketing at NC State, adds, “Anecdotally, we often hear stories from friends and acquaintances about how daylight saving time affects them. We wanted to see if there was data supporting the idea that moving the clock ahead one hour actually affects our behaviors.”

The researchers conducted two studies to investigate the impact of DST on consumer behavior.

Study One: Snack Consumption

In the first study, researchers analyzed data from a U.S.-based packaged food company. The company collected data from a nationally representative cohort of participants between 2004 and 2010.

Participants used mobile devices to record detailed data on their snack consumption for two weeks, including what they ate, when they ate it, and the quantity consumed.


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“This data set is remarkable because it spans multiple years and tracks specifically what people are eating,” Janakiraman explains. “Many other data sets look at what people buy, or rely on people remembering what they’d eaten. This data was collected using a methodology that had study participants enter their consumption in the moment.”

The dataset included consumption data from days leading up to and following the onset of DST, as well as from consumers in regions of the U.S. that do not observe DST, serving as a control group.

Study Two: Gym Attendance

In the second study, researchers analyzed data from a company operating hundreds of fitness centers across the U.S. The company provided data on the number of customers visiting the gym in the week before and after the onset of DST. Again, data from fitness centers in regions that do not observe DST served as a control group. This dataset covered a single year.

Study Results

The results from both studies were significant and pointed to negative effects on health-related behaviors following the onset of DST.

The first study found that people ate more processed snacks after DST began, particularly later in the day and on overcast days. This suggests a link between the time change and increased unhealthy eating habits.

The second study revealed a decline in gym visits following the onset of DST. This effect was more pronounced among irregular gym users, with those having a consistent gym schedule being less affected by the time change. Additionally, the negative impact was greater for individuals living further from their gyms.

Rishika comments, “This effect was stronger in people who are irregular gym users. People who have a regular gym schedule were less affected by the time change. This negative effect of daylight saving time was also more pronounced the further people live from the gym."

Implications and Recommendations

The findings underscore the need for consumers to be proactive in maintaining healthy habits during the transition to DST. “One big takeaway for consumers is that we need to be mindful about trying to maintain healthy habits after daylight saving time,” says Rishika.

From a policy and business perspective, Janakiraman suggests, “The study also tells us that daylight saving time is an opportunity for companies to engage in outreach efforts that help consumers adjust to the time change. The findings also suggest there is a need for public policies that support people when we’re setting the clock forward.”

The research highlights the adverse effects of DST on consumer behavior, particularly in terms of increased consumption of processed snacks and reduced gym attendance. These findings offer valuable insights for consumers, businesses, and policymakers aiming to mitigate the negative health impacts associated with DST.

The paper, “Spring Forward = Fall Back? The Effect of Daylight Saving Time Change on Consumers’ Unhealthy Behavior,” is published in the Journal of Marketing. Co-authors include Harsha Kamatham of the University of Manitoba; Sven Feurer of Bern University of Applied Sciences; Bhavna Phogaat of the University of South Carolina; and Marina Girju of California Baptist University.

While the shift to daylight saving time is a well-established practice, its implications on health and consumer behavior warrant further attention and action. By understanding and addressing these impacts, we can better support healthier lifestyles and well-being during this biannual transition.

For more science news stories check out our New Discoveries section at The Brighter Side of News.


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Joshua Shavit
Joshua ShavitScience and Good News Writer
Joshua Shavit is a bright and enthusiastic 17-year-old student with a passion for sharing positive stories that uplift and inspire. With a flair for writing and a deep appreciation for the beauty of human kindness, Joshua has embarked on a journey to spotlight the good news that happens around the world daily. His youthful perspective and genuine interest in spreading positivity make him a promising writer and co-founder at The Brighter Side of News.