High-Fiber Diet May Reduce Heart Disease Risk in Night Shift Workers

Working night shifts can increase your odds of developing coronary heart disease (CHD). But eating a diet high in fiber may help to mitigate this risk, a new study suggests.

Published in the European Journal of Epidemiology, the study reviewed data from more than 220,000 British adults and found that regular night shift workers who ate little fiber in their diets tended to have a higher risk of CHD than their peers who ate more fiber.

The findings suggest that eating a diet with fiber-rich foods—such as whole grains, vegetables, and legumes—could be a simple way for regular night shift workers to reduce their risk of heart disease.

How does working at night affect your health?

In the United States, millions of workers are employed in regular night shift work; these late shifts are critical to the running of essential services, such as healthcare, firefighting, police work, and transportation.

However, a growing body of evidence suggests that working at night can present significant health concerns. To date, researchers have linked night shift work to increased risks for cardiovascular disease, sleep disorders, and poor mental health.

“Human biology follows a natural daily rhythm. Many recovery processes that are essential for maintaining the circulatory system, including the heart, take place at night when people typically rest. During sleep, the heart and blood vessels experience a period of reduced strain, allowing them to recover and prepare for the physical and psychological demands of the following day,” senior study author Prof. Christian Benedict, a professor of pharmacology at Uppsala University, told Technology Networks.

 

“Working night shifts disrupts these important nocturnal recovery and repair processes. In addition, daytime sleep after a night shift is often shorter and of lower quality compared to nighttime sleep. Over time, these factors can increase the risk of cardiovascular diseases, including CHD.”

In this latest study, researchers analyzed records from 222,801 British adults who were employed as either daytime workers, shift workers with no/occasional night shifts, or regular night shift workers. The data, taken from the UK Biobank, were linked with medical record data in order to study any associations between their dietary intake, work shift patterns, and cardiovascular health.

“The UK Biobank is one of the largest cohort studies ever conducted, including a wide range of health and disease-related variables. In our analysis, we focused on daily fiber intake and weekly meat intake, two dietary variables assessed among hundreds of nutritional factors,” Benedict said.

“We chose to concentrate on these two variables because previous research has shown that they influence heart health. However, whether higher daily fiber intake or the absence of meat consumption—both considered heart-health–promoting behaviors—provides additional benefits for night shift workers, a demographic at increased risk of heart disease, has not yet been investigated. In our analysis, we controlled for a range of potential confounders, including physical activity, smoking status, and body mass index.”

More fiber intake can protect heart health

Among the study cohort, those working regular night shifts did have a higher CHD incidence than other worker groups, as expected.

Compared to those in daytime work, CHD risk was higher among those who reported lower daily fiber intake in both occasional and regular night shift worker groups. However, this risk was significantly attenuated in the shift workers who ate more fiber.

A moderate intake of around 19 grams of fiber per day was associated with a lower CHD risk for regular night shift workers, while in sporadic night shift workers, approximately 15 grams daily was enough to attenuate risk. UK dietary guidelines recommend 30 grams of fiber per day, though most adults average around 20 grams per day.

“Dietary fiber can promote the production of short-chain fatty acids (SCFAs) through fermentation by the gut microbiome. SCFAs have been implicated in the regulation of metabolic processes, including pathways relevant to cardiovascular health,” Benedict explained.

“Higher fiber intake has also been associated with improved blood lipid profiles. In addition, emerging evidence suggests a potential link between dietary fiber, gut microbiota composition, and sleep quality, although this relationship remains an area of ongoing research. Together, these mechanisms may partly explain the observed association between higher fiber intake and improved heart health.”

Those who avoided eating meat in their diet were also associated with a 10.4% lower risk for CHD, compared with meat eaters. However, no significant association was seen between meat intake and work schedules.

“Refraining from meat consumption—commonly observed among individuals adhering to a vegetarian-like dietary pattern—was associated with a lower risk of heart disease. While higher fiber intake appeared to offer greater benefit among night shift workers, the association between absence of meat intake and improved heart health was similar for both night shift workers and daytime workers,” Benedict said.

Diet could complement other heart-healthy behaviors

The fiber intakes measured in this study should not be taken as dietary recommendations, the researchers point out. But the general trends uncovered in this analysis do suggest a pattern; that higher dietary fibre intake is linked to lower risks of heart disease in night shift workers.

“As this is a correlational study, causal inferences cannot be drawn,” Benedict emphasized. “To better understand the potential effects of fiber intake among night shift workers, interventional studies are needed. For example, a randomized controlled trial could assign one group of night shift workers to a high-fiber diet and another group to a low-fiber diet. By comparing cardiovascular biomarkers and other heart-related measures before and after a defined intervention period (e.g., three months), researchers could assess whether higher fiber intake leads to measurable improvements in cardiovascular health among this high-risk population.”

Still, the trends suggest that increasing fiber intake may be a useful addition to the toolkit of other strategies known to protect heart health, such as regular physical activity.

“Consuming foods high in fiber may offer cardiovascular health benefits. However, it is important to recognize that increased fiber intake should complement other heart-healthy lifestyle behaviors, including regular physical activity and sufficient sleep,” Benedict said. “While a high-fiber diet can contribute to improved heart health, it cannot compensate for major cardiovascular risk behaviors such as smoking and excessive alcohol consumption.”

Reference: Nôga DA, Meth EMS, Pacheco AP, Cedernaes J, Xue P, Benedict C. Night shift work, dietary patterns, and coronary heart disease. Eur J Epidemiol. 2026. doi: 10.1007/s10654-026-01362-w

Prof. Christian Benedict was speaking to Alexander Beadle, Science Writer and Editor for Technology Networks.

 

About the interviewee:

 

Prof. Christian Benedict completed his studies in Human Nutrition at the University of Kiel, Germany, and earned a PhD in Human Biology at the Medical Faculty in Lübeck, Germany. He conducted postdoctoral research in Sweden at Uppsala University, became an associate professor (Docent) in neuroscience, and, since June 2025, serves as a professor of pharmacology at Uppsala University.

 

Benedict leads a research team investigating the adverse health effects of disrupted sleep and circadian misalignment, including the impact of night shift work. He studies how insufficient sleep and circadian disruption influence weight regulation, glucose metabolism, and brain health. Through clinical and population-based studies, his work advances understanding of the biological mechanisms linking sleep and circadian disturbances to cardiometabolic and neurological outcomes and informs strategies that promote long-term health.