COVID-19 and metabolic syndrome are devastating pandemics. Effective control of metabolic parameters and their dysfunction may help prevent or minimize the acute and devastating effects of SARS-CoV-2 by reducing the local inflammatory response and blocking the entry of the virus into cells. With such consideration in mind, we gathered data from dietary surveys conducted in nine European countries to explore the relationship between actual clock hour of the large dinner meal and also interval in minutes between it and sunset in the respective countries and death rate above the median rate of per one million people as an index of mortality due to COVID-19 infection. Clock time of the dinner meal varied between 16:00 and 21:00 h across the European counties sampled, and the correlation between dinner mealtime and death rate was strongly correlated, R = 0.7991 (two-tailed p = 0.0098), with R2 explaining 63% of the variation within the data. This strong linear positive correlation indicates that the later the clock time of the dinner meal, the higher is the death rate (and vice versa). The relationship between meal timing in reference to sunset, utilized as a gross surrogate marker of the activity/rest synchronizer of circadian rhythms, and death rate was negative and even slightly stronger, R = -0.8025 (two-tailed p = 0.0092), with R2 explaining 64% of the variation within the data. This strong linear negative correlation indicates that the shorter the interval between the dinner meal and sunset, i.e., the closer the time of the largest meal of the day to bedtime, the greater is the death rate (and vice versa). Our preliminary approach to nighttime eating, in terms of the day's largest caloric intake, as a risk factor for the predisposing conditions of obesity, metabolic syndrome, type 2 diabetes, and other commonly associated comorbidities of being overweight, and death from COVID-19 infection reveals strong correlation with the time of the dinner meal, both in terms of its actual clock and circadian time.
Keywords: COVID-19; chrononutrition; circadian clock; dinner meal timing; metabolic syndrome; obesity.