The impairment of adaptive mechanisms of functional systems of the body plays an important role in the occurrence of gastrointestinal diseases. This impairment is caused by unfavorable ecological and radiation conditions, external stress factors, food containing carcinogens, macro - and microelements deficiency. Technogenic environmental pollution contributes to decrease in the level of iodine in the body and more severe course of thyroid pathology. Diseases of the digestive and endocrine systems and their combination will occupy one of the leading places among the existing pathologies according to the forecasts of WHO experts in the XXI century. Adaptation of the body to various environmental influences is the most important factor in the quality of life. The relevance of the study was determined by the high incidence of psychological disadaptation, borderline personality disorders and, as a consequence, decrease in the quality of life in patients with gastrointestinal pathology and hypothyroidism. The article presents the results of comparative analysis of the quality of life indications of patients with gastric ulcer and / or gastroesophageal reflux disease in combination with hypothyroidism. The Russian-language analogue of the international questionnaire SF36 was used to analyze the indicatoions of patients' quality of life. The results of the study will allow to formulate the diagnosis exactly and organize adequate, comprehensive multidisciplinary treatment. © 2021 Medicinska Naklada Zagreb. All rights reserved.