Growing evidence supports the hypothesis that dietary factors may play a role in systemic low-grade chronic inflammation. Summary evidence from randomized controlled trials has shown substantial effects on biomarkers of inflammation following the adoption of plant-based diets (including, but not limited to, the Mediterranean diet), while consistent findings have been reported for higher intakes of whole grains, fruits, and vegetables and positive trends observed for the consumption of legumes, pulses, nuts, and olive oil. Among animal food groups, dairy products have been shown to have the best benefits on biomarkers of inflammation, while red meat and egg have been shown to have neutral effects. The present review provides an overview of the mechanisms underlying the relation between dietary factors and immune system, with a focus on specific macronutrient and non-nutrient phytochemicals (polyphenols) and low-grade inflammation. Substantial differences within each macronutrient group may explain the conflicting results obtained regarding foods high in saturated fats and carbohydrates, underlying the role of specific subtypes of molecules (i.e., short-chain fatty acids or fiber vs. long chain fatty acids or free added sugars) when exploring the relation between diet and inflammation, as well as the importance of the food matrix and the commixture of foods in the context of whole dietary patterns. Dietary polyphenols and oligopeptides have been hypothesized to exert several functions, including the regulation of the inflammatory response and effects on the immune system. Overall, evidence suggests that dietary factors may affect the immune system regardless of obesity-related inflammation.

The interaction between nutrition and the immune system is very complex. In particular, at every stage of the immune response, specific micronutrients, including vitamins and minerals play a key role and often synergistic, and the deficiency of only one essential nutrient may impair immunity. An individual’s overall nutrition status and pattern of dietary intake (comprised of nutrients and non-nutritive bioactive compounds and food) and any supplementation with nutraceuticals including vitamins and minerals, can influence positively or negatively the function of the immune system. This influence can occur at various levels from the innate immune system and adaptive immune system to the microbiome. Although there are conflicting evidence, the current results point out that dietary supplementation with some nutrients such as vitamin D and zinc may modulate immune function. An update on the complex relationship between nutrition, diet, and the immune system through gut microbiota is the aim of this current review. Indeed, we will provide the overview of the link among immune function, nutrition and gut microbiota, paying particular attention at the effect of the Mediterranean diet on the immune system, and finally we will speculate the possible role of the main one functional supplements on immune function.

Coffee is one of the most popular beverages worldwide; however, its impact on health outcomes and adverse effects is not fully understood. The current review aims to establish an update about the benefits of coffee consumption on health outcomes highlighting its side effects, and finally coming up with an attempt to provide some recommendations on its doses. A literature review using the PubMed/Medline database was carried out and the data were summarized by applying a narrative approach using the available evidence based on the literature. The main findings were the following: first, coffee may contribute to the prevention of inflammatory and oxidative stress-related diseases, such as obesity, metabolic syndrome and type 2 diabetes; second, coffee consumption seems to be associated with a lower incidence of several types of cancer and with a reduction in the risk of all-cause mortality; finally, the consumption of up to 400 mg/day (1–4 cups per day) of caffeine is safe. However, the time gap between coffee consumption and some drugs should be taken into account in order to avoid interaction. However, most of the data were based on cross-sectional or/and observational studies highlighting an association of coffee intake and health outcomes; thus, randomized controlled studies are needed in order to identify a causality link.

Obesity and metabolic disorders remain major global health concerns, traditionally attributed to excessive caloric intake and poor diet quality. Recent studies emphasize that the timing of meals plays a crucial role in determining metabolic health. This review explores chrononutrition, a growing field that examines how food intake patterns interact with endogenous circadian rhythms to influence energy balance, glucose and lipid metabolism, and cardiometabolic risk. The circadian system, which includes a central clock in the suprachiasmatic nucleus and peripheral clocks in metabolic tissues, regulates physiological functions on a 24 h cycle. While light entrains the central clock, feeding schedules act as key synchronizers for peripheral clocks. Disrupting this alignment—common in modern lifestyles involving shift work or late-night eating—can impair hormonal rhythms, reduce insulin sensitivity, and promote adiposity. Evidence from clinical and preclinical studies suggests that early time-restricted eating, where food intake is confined to the morning or early afternoon, offers significant benefits for weight control, glycemic regulation, lipid profiles, and mitochondrial efficiency, even in the absence of caloric restriction. These effects are particularly relevant for populations vulnerable to circadian disruption, such as adolescents, older adults, and night-shift workers. In conclusion, aligning food intake with circadian biology represents a promising, low-cost, and modifiable strategy to improve metabolic outcomes. Integrating chrononutrition into clinical and public health strategies may enhance dietary adherence and treatment efficacy. Future large-scale studies are needed to define optimal eating windows, assess long-term sustainability, and establish population-specific chrononutritional guidelines.

Background/Objectives: With the increasing life expectancy and, as a result, the aging of the global population, there has been a rise in the prevalence of chronic conditions, which can significantly impact individuals’ health-related quality of life, a multidimensional concept that comprises an individual’s physical, mental, and social wellbeing. While a balanced, nutrient-dense diet, such as Mediterranean diet, is widely recognized for its role in chronic disease prevention, particularly in reducing the risk of cardiovascular diseases and certain cancers, its potential benefits extend beyond these well-known effects, showing promise in improving physical and mental wellbeing, and promoting health-related quality of life. Methods: A systematic search of the scientific literature in electronic databases (Pubmed/Medline) was performed to identify potentially eligible studies reporting on the relation between adherence to the Mediterranean diet and health-related quality of life, published up to December 2024. Results: A total of 28 studies were included in this systematic review, comprising 13 studies conducted among the general population and 15 studies involving various types of patients. Overall, most studies showed a significant association between adherence to the Mediterranean diet and HRQoL, with the most significant results retrieved for physical domains of quality of life, suggesting that diet seems to play a relevant role in both the general population and people affected by chronic conditions with an inflammatory basis. Conclusions: Adherence to the Mediterranean diet provides significant benefits in preventing and managing various chronic diseases commonly associated with aging populations. Furthermore, it enhances the overall health and quality of life of aging individuals, ultimately supporting more effective and less invasive treatment approaches for chronic diseases.

Coronavirus disease 2019 (COVID-19) has quickly become a global pandemic. Reports from different parts of the world indicate that a significant proportion of people who have recovered from COVID-19 are suffering from various health problems collectively referred to as “long COVID-19”. Common symptoms include fatigue, shortness of breath, cough, joint pain, chest pain, muscle aches, headaches, and so on. Vitamin D is an immunomodulatory hormone with proven efficacy against various upper respiratory tract infections. Vitamin D can inhibit hyperinflammatory reactions and accelerate the healing process in the affected areas, especially in lung tissue. Moreover, vitamin D deficiency has been associated with the severity and mortality of COVID-19 cases, with a high prevalence of hypovitaminosis D found in patients with COVID-19 and acute respiratory failure. Thus, there are promising reasons to promote research into the effects of vitamin D supplementation in COVID-19 patients. However, no studies to date have found that vitamin D affects post-COVID-19 symptoms or biomarkers. Based on this scenario, this review aims to provide an up-to-date overview of the potential role of vitamin D in long COVID-19 and of the current literature on this topic.