Beat the blues with food? A new study adds to evidence that mealtime can affect mental health, including mood levels linked to depression and anxiety. Investigators from Brigham and Women’s Hospital, a founding member of the Mass General Brigham health care system, designed a study that simulated night work and then tested the effects of eating during the day and night versus eating only during the day. The team found that, among participants in the daytime and nighttime eating group, levels of depression-like mood increased by 26 percent and levels of anxiety-like mood by 16 percent. Participants in the daytime-only eating group did not experience this increase, suggesting that mealtime may affect mood vulnerability. The results are published in of Proceedings of the National Academy of Sciences.
“Our findings provide evidence for meal timing as a novel strategy to potentially minimize mood vulnerability in individuals experiencing circadian mismatch, such as people engaged in shift work, experiencing jet lag, or suffering from mood disorders. of the circadian rhythm,” said the co-correspondent. author Frank AJL Scheer, PhD, Director of the Medical Chronobiology Program in Brigham’s Division of Sleep and Circadian Disorders. “Future studies in shift workers and clinical populations are needed to definitively determine whether changes in meal timing can prevent their increased mood vulnerability. Until then, our study brings a new ‘player’ to the table : the time we eat matters for our mood.”
Shift workers comprise up to 20 percent of the workforce in industrial societies and are directly responsible for many hospital services, factory work, and other essential services. Shift workers often experience a mismatch between their central circadian clock in the brain and daily behaviors, such as sleep/wake and fasting/eating cycles. Importantly, they also have a 25 to 40 percent higher risk of depression and anxiety.
“Shift workers — as well as individuals experiencing circuit disruptions, including jet lag — may benefit from our mealtime intervention,” said co-corresponding author Sarah L. Chellappa, MD, PhD, who completed the work in this project while at Brigham. Chellappa is now at the Department of Nuclear Medicine, University of Cologne, Germany. “Our findings open the door to a new behavioral sleep/circadian strategy that may also benefit individuals experiencing mental health disorders. Our study adds to a growing body of evidence revealing that strategies that optimize sleep and circadian rhythms can help promote mental health.”
To conduct the study, Scheer, Chellappa and colleagues enrolled 19 participants (12 men and 7 women) for a randomized controlled trial. Participants were subjected to an Enforced Desynchrony protocol in dim light for four 28-hour “days” such that by the fourth “day” their behavioral cycles were reversed by 12 hours, simulating night work and caused circular mismatch. Participants were randomly assigned to one of two meal time groups: Day and Night Meal Control Group, which had meals according to a 28-hour cycle (resulting in nighttime and daytime eating, which is typical for workers night) and the Daily Meals Only Intervention Group, which had meals on a 24-hour cycle (resulting in eating only during the day). The team assessed levels of depression-like mood and anxiety every hour.
The team found that meal timing significantly affected participants’ mood levels. During the simulated night shift (day 4), those in the daytime and nighttime meal control group had depression-like mood levels and anxiety-like mood levels compared to baseline (day 1). In contrast, there were no changes in mood in the Daily Meal Intervention Group during the simulated night shift. Participants with a greater degree of circadian misalignment experienced more depression-like mood and anxiety.
“Meal timing is emerging as an important aspect of nutrition that can affect physical health,” Chellappa said. “But the causal role of mealtime on mental health remains to be tested. Future studies are required to determine whether changes in mealtime can help individuals experiencing depressive and anxiety/anxiety disorders.”
Materials provided by Brigham and Women’s Hospital. Note: Content may be edited for style and length.