Cut-off for the Mediterranean diet score to identify subjects with morning chronotype in middle-aged Italian adults

We have recently published the article entitled “Chronotype and Adherence to the Mediterranean Diet inObesity: Results from the Opera Prevention Project” byMuscogiuri.1Circadian rhythm is defined as an individual’s abilityto adapt to the day-night cycle of the earth’s 24 hoursday 2. This central circadian clock is located in the anterior hypothalamus in the brain, in particular in thesuprachiasmatic nucleus.2 The chronotype or circadianpreference is one of different circadian phase markers,and it reflects an individual’s attitude to carry out dailyactivities in a preferred time of the day. According thisindividual’s attitude, subjects can be classified as having morning, intermediate or evening chronotype.3Dietary intake has often been linked to chronotype,in particular subjects with evening chronotype have atendency to skip breakfast, to delay main meal timing,to have lower intake of vegetables and/or fruit, higherpreference for sugar beverages/foods and alcohol consumption, thus having a lower adherence to healthydiet.2, 4 In addition, it is well-known that diet qualityhas an impact on subjects’ health status.2, 4 Meal withhigh calorie intake, mostly if it is consumed late in theevening, is associated with increased odds of develop ing overweight and obesity.2, 4, 5 Of interest, frequentbreakfast skipping could lead to derangements glucosehomeostasis through affecting postprandial insulin concentration.6 Several evidence investigated the relationship between diet and chronotype health.2, 4 However, todate, only few studies have investigated the associationbetween chronotype and adherence to the Mediterranean diet in adults. As well known, Mediterranean dietis an anti-inflammatory and antioxidant dietary pattern,7and its high adherence has been associated with a number of cardio-metabolic health outcomes, such as lowerrisk of neuroendocrine tumors,8 polycystic ovary syndrome,9 breast cancer10 and obesity.11Given the role association of diet with chronotype,we aimed to investigate the association between adherence to the Mediterranean diet and chronotype scoreand suggest that a specific cut-off of Prevención conDieta Mediterránea (PREDIMED) Score, which identifies subjects with evening chronotype.