Obesity is a global health concern with rising proportion of existing cases, and it is associated with numerous comorbidities, including an increased risk of infections and a more severe disease course. The main cause of obesity is an energetic imbalance due to increased caloric intake and little expenditure, which leads to metabolic and hormonal changes that increase the risk of developing type 2 diabetes mellitus (T2DM), heart disease, and stroke. T2DM is a non-reversible but preventable condition, and overweight and obesity are major risk factors.

The immune system plays a critical role in protecting the body against infections, and a weakened immune system due to obesity can lead to an increased risk of infections, including postoperative and nosocomial infections. Nutrition and diets can promote the functioning of the immune system as a preventive measure by reducing both inflammation and oxidative stress that might be caused by various factors. The Mediterranean diet, rich in fruits, vegetables, and fiber, has been associated with a reduced risk of T2DM and other chronic diseases, as well as a reduced risk of infection. Moreover, bioactive compounds such as polyphenols also have a great impact on immunity.

In recent years, marine organisms, especially brown seaweeds, have been highlighted as potential natural sources of bioactive compounds and useful metabolites, with many biological and physiological activities to be used in functional foods or in human nutraceuticals for their potential health benefits.

The main objective of this project is to study the influence of beneficial diets on the immune system of prediabetic patients and its potential to counteract infections. The project will use a clinical, an in vitro and an in vivo approach to study the influence of a seaweed supplement and a diet rich in components from a Mediterranean diet on a Salmonella typhimurium infection in prediabetic subjects. The study will assess immune system, inflammation, gut microbiota, bile acids, and perform metabolic and lipidomic analysis in different samples collected from the different cohorts of the study.

The results of this study will provide evidence on the potential of these nutritional interventions to counteract infection, which are of high relevance to society to reduce the burden of T2DM and obesity. This project has the potential to lead to the development of novel interventions to improve immune function and prevent infections in prediabetic patients and overweight people. These findings may have broader implications for the prevention and treatment of infectious diseases in other patient populations. In summary, this research could contribute to the development of public health strategies to improve the health of populations worldwide.