This dissertation investigates the burden of diabetes mellitus (DM) in the European Union (EU) and its correlation with existing policies, both at the EU and national levels, along with their association with DM. Moreover, it undertakes an examination of lifestyle and socioeconomic factors. Additionally, the study analyses public discourse within the EU concerning front-of-pack nutrition labelling. In a comprehensive study on legislation targeting DM, obesity, and non-communicable diseases (NCDs) in EU, a total of 1,099 relevant legislations were collected and assessed against the "Toward an EU Strategic Framework for the Prevention of NCDs," a joint publication by European Public Health Alliance (EPHA) and World Health Organization (WHO) "Global Report on Diabetes". The analysis revealed that 22 legislations primarily focused on the prevention of DM, NCDs, and obesity, with only five specifically designed for DM prevention. These legislations spanned from 1968 to 2022, with 366 currently in effect. Among the identified legislations, there were six binding legislations and 17 non-binding legislations, with the European Commission (EC) as the primary author of 13 of them. EuroVoc terms were available in 853 legislations, predominantly in the domain of "social questions" and "public health." A longitudinal perspective showed an increase in legislations over time, with a shift in focus from "trade" to "social questions" and "epidemic" subdomains. Additionally, the assessment revealed a life-course approach as the most common classification, with food-related laws playing a prominent role. Further analysis examined the impact of nutrition and physical activity policies on DM and its risk factors across EU member states. The study found variations in DM prevalence, with a predicted 6.94% prevalence in the EU in 2014. Portugal had the highest rates, while Lithuania had the lowest. National DM plans and registries differed among member states, with policies like "Nutrition label standards and regulations on the use of claims and implied claims on food" implemented universally, while others were less frequently adopted. Country-level regression revealed that demographic, socioeconomic, and lifestyle factors had a greater influence on DM prevalence than policy availability. In a separate assessment of diabetes prevalence in Slovakia between 2009, 2014, and 2019, the study found an increase from 6.1% to 9.8%. Notably, women had a lower likelihood of DM than men, and certain age groups exhibited lower associations with DM. Higher education and employment were linked to a lower likelihood of DM, while higher body mass index (BMI) and lack of physical activity increased the likelihood. Importantly, there was no significant association between DM and fruit and vegetable consumption, and geographical regions in Slovakia did not exhibit a statistically significant association with DM prevalence. Finally, the study analysed tweets in the EU regarding front-of-pack nutrition labelling. The study observed a multitude of tweets, with the majority being original and containing opinions and announcements. Different countries, including the United Kingdom, Spain, France, Belgium, Germany, Ireland, the Netherlands, and Italy, were major contributors to the discussions, although most tweets were contained within national boundaries. The topics covered various aspects of nutritional food labelling, the food industry, healthy vs. unhealthy foods, EU regulations, political conflict, science, and education. The Nutri-Score label emerged as the most discussed, with both supporters and opponents expressing their views. Sentiment analysis of the tweets generally indicated a negative tone, with tweets related to the food industry receiving more positive feedback compared to those involving political conflict. In conclusion, this dissertation offers a comprehensive examination of the burden of DM in the EU, highlighting the multifaceted interplay between existing policies, lifestyle factors, and socioeconomic determinants, while also shedding light on emerging issues such as front-of-pack nutrition labelling and its reception among EU citizens.