Introduction: The main objective of this study is to investigate the dietary and lifestyle habits and associated diseases and nutritional status in patients indicated for esophagogastroduodenoscopy (EGDS) and patients diagnosed with gastroesophageal reflux disease (GERD) and gastritis after EGDS to determine a possible role of the nurse in patient education. Materials and methods: 97 people participated in the study, 57 (58,8%) of whom were women. Most respondents, 50 (51,5%), were between 31and 60 years old, 34 (35,1%) were 61 years or older, while 13 (13,4%) were between 18 and 30 years old. For each respondent, a questionnaire was completed on the presence of comorbidities, lifestyle habits, medication intake and the Mediterranean Diet Serving Score (MDSS) questionnaire. In addition, all subjects underwent an EGDS, a rapid urease test for the detection of Helicobacter pylori (HP) from gastric mucosal biopsies, and their height and weight were measured, from which the body mass index (IMT) was then calculated. Results: 19 (19,8%) of respondents take painkillers or medication for blood clotting, while 30 (30,9%) of respondents take medication for stomach pain. 41 (43,6%) of respondents suffer from nausea, 31 (32,6%) have experienced changes in their body weight in the last 6 months, 35 (36,1%) of respondents smoke, while 81 (83,5%) of respondents drink coffee. 56 (57,7%) of the respondents eat breakfast daily, 75 (77,3%) eat cooked food daily, and 29 (29,9%) of the respondents eat 5-6 meals per day. In addition, 26 (26,8%) respondents drink carbonated drinks more than twice a week, while 37 (38,5%) respondents like to eat spicy (peppery, sour, salty) food. 11 (11,3%) people have HP infection, 47 (48,5%) people have GERD, 61 (62,9%) people have gastritis, and only 6 (6,4%) people adhere to the Mediterranean diet. The results show that statistically significantly more men smoked compared to women (p=0,020), while women were statistically significantly more likely to eat breakfast daily (p=0,039). The results also show that men drink carbonated drinks significantly more often (p=0,020). Non-smokers were significantly more likely to eat breakfast daily (p=0,001), significantly more likely to eat cooked food (p=0,047) and significantly less likely to consume highly seasoned food (p=0,002) than smokers. The results also show that statistically significantly more respondents with GERD eat more spicy foods than those with gastritis (p=0,061). The results also show that people with GERD are statistically significantly more likely to suffer from other gastric diseases (p=0,091). Conclusions: The results indicate a high frequency of GERD and gastritis in the patient population with symptoms suggestive of EGDS. A high frequency of undesirable lifestyle habits (such as frequent consumption of coffee, carbonated beverages and spicy food, as well as smoking and skipping breakfast) is also evident in this population studied, especially in men. In addition, an overwhelmingly low number of respondents follow the postulates of the Mediterranean diet. All this suggests that healthcare professionals, especially nurses, need to be educated to change the aforementioned undesirable lifestyle habits and adopt dietary recommendations based on the Mediterranean diet, as the aforementioned habits are associated with the development and incidence of GERD and gastritis, as well as with health in general.