Could eating at markedly different times on weekends compared with weekdays—what scientists call “food jet lag”—pose health risks? A recent French study suggested that, among men, this pattern might be linked to higher risks of cardiovascular diseases and, more specifically, coronary heart disease. What should we actually take away from these findings?
Between 14% and 21% higher risk for each additional hour
The term “jet lag” is generally related to the time difference experienced when traveling by plane. When paired with the qualifier “alimentaire,” the expression retains the same core meaning regarding eating behavior, more precisely meal times between weekdays and the weekend. Thus, for example, someone experiencing food jet lag would have meals during the week at 7:00, 12:30, and 20:00, but on weekends these times could shift to 10:30, 14:30, and 22:00.
A team of researchers from Université Sorbonne Paris Nord and Inserm, among others, conducted a study on the topic. According to the results published in Communications Medicine on September 1, 2026, each additional hour of food jet lag in men would raise the risk of developing cardiovascular diseases by 14%, and would increase by 21% the risk of developing coronary heart disease.
“This first study suggests that changes in meal timing between weekends and weekdays could play a role in the onset of cardiovascular diseases, independent of sleep duration and the quality of the diet, particularly among men.”, according to the Inserm press release about the study.
Conflicting signals sent to the peripheral clocks of organs
To be precise, the risks cited above rise with food jet lag and this holds true whether one moves meal times earlier or later during the weekend compared with the weekdays. According to the researchers, the problem comes from the irregular rhythm itself, a source of disruption to the body, rather than simply allowing oneself to sleep in. Moreover, it should be noted that the excess risk discussed here was calculated after removing the impacts of other factors such as age, smoking, physical activity, sleep duration, or the nutritional quality of the foods consumed.
The human body possesses a central biological clock that activates under the influence of sunlight. By contrast, organs such as the liver, the pancreas, adipose tissues, etc., have peripheral clocks that synchronize to meal intake. Thus, abruptly changing weekend meal times sends conflicting signals to the body—the well-known food jet lag. In the long run, this desynchronization disrupts blood glucose, blood pressure, and fat metabolism, wearing down the cardiovascular system.
Finally, a question arises: why does the study’s conclusion seem to apply only to men? In reality, the scientists observed no statistically significant association among women. They suggest this could be due to possible physiological or hormonal differences or, potentially, by differences in exposure to work schedules. However, the authors stated that these initial findings are observational. Consequently, further studies are expected to go much further in understanding the phenomenon.
