## 4 Discussion
Of note, in sex-specific analysis, lean mass remained unchanged. This issue is important, since the loss of lean mass can lower resting metabolic rate, cause fatigue and increase injury risk [43, 44]. Moreover, it can increase the risk of sarcopenia, which worsens quality of life and prognosis, especially in disease states [45]. It is possible that the Mediterranean diet pattern followed, along with enhancement of physical activity through the CDSS, minimized the risk of lean mass loss [46]. Reductions in HbA1c and triglycerides were also documented in the present work, underlying the importance of Mediterranean diet adherence in glycemia management [47], cardiovascular disease prevention [48], and the contribution of technology to the same direction [49]. Indeed, a diet rich in antioxidants, fiber and mono-unsaturated and unsaturated fatty acids and low in saturated fatty acids, as in the Mediterranean dietary pattern [50], exerts anti-inflammatory actions by targeting several mediators, such as the Platelet Activating Factor (PAF) [51, 52] and can improve glycemia [53, 54]. Several CDSS have been used for glucose management in a hospital setting and for cardiovascular disease prevention and management, as recently reviewed elsewhere [33, 55]. However, the Nutrinet(r) CDSS was administered by a professional dietitian, while most CDSS were administered by medical doctors and nurses [55], even if they were directly related to food consumption, such as \"MyFood\" [35]. In addition, the identification of weight loss predictors may assist in ascertaining the probable outcomes of lifestyle interventions [56]. Paying attention to baseline subjects' characteristics affecting weight loss is thus important, and possibly population- and situation-specific. A recent review identified that several patient-related variables affect weight loss, such as male gender, older age, presence of cardiometabolic diseases and low fat intake [56]. Although sex-specific predictors of weight loss have been reported [57], in most studies, sex is only included as a covariate in models and sex-specific models are not applied [58], with some exceptions [59, 60]. In the present study, sex-specific analysis was performed in both pre- and post-intervention results as well as in the models for prediction of weight loss. However, age and gender were not identified as predictors of % weight loss. A pattern characterized by increased BMI and lean mass was positively related to the extent of weight loss in women. In another study, pre-treatment fat mass was related to weight loss in males [59]. It is thus possible that high BMI is connected to high lean mass and increases energy expenditure, facilitating weight loss [61]. Serum triglycerides were inversely related to % weight loss in the total sample and men as a possible trend. This finding is in line with data suggesting that triglycerides changes have a positive relationship with weight change (r = 0.82) [62]. In addition, sex differences have been reported in the relationship of weight and lipoproteins [63], with triglyceride kinetics being affected mostly in men than women [64; 65], which is in line with the trend observed in the present work. In addition, the present study was conducted in the COVID-19 pandemic, which has been per se associated with weight changes. According to a recent meta-analysis, self-reported body weight increased in 11.1-72.4% of individuals and decreased in 7.2-51.4% of individuals [66]. Moreover, predictors of body weight may be different during COVID-19 compared to other periods, since emotional stress, telework and confinement took place [67]. For example, a study in Greek volunteers showed that sleep impairment was present during the lockdown, and it was related to changes in dietary and physical activity habits [68]. In addition, health issues affecting food intake and activity patterns following acute or long COVID-19 infection are not to be excluded.