Methods: 1. st stage - Study design: An open pilot prospective clinical trial. The study included 71 adult patients with T2D and hypertension for the Ramadan fast's (RF) weight loss. 2. nd stage - Study design: A 24-week open label, prospective, multicenter, comparative clinical trial with the intention-to-treat analysis. Participants. Totally 150 adult patients with MS aged 35-65 years and with BMI≥27 kg/m2 for Asian will be included. They will be distributed in three comparative groups: drug treatment, surgery and diet. Primary endpoints: weight loss, fasting blood glucose, blood insulin level, systolic/diastolic BP. Secondary endpoints: blood lipids, heel bone mineral density (HBMD), and ejection fraction (EF). Expected results: A prospective multicenter clinical study will provide comparative results on life expectancy, glycemic and lipid metabolism, quality of life, cost-effectiveness of pharmacological, bariatric and dietary methods of weight loss in patients with obesity, T2D and hypertension. As a result of the research, the following will be published: 1. at least three articles and/or reviews in peer-reviewed scientific publications indexed in the Science Citation Index Expanded of the Web Of Science database and/or having a Cite Score percentile in the Scopus of at least 50; 2. at least 1 patent for an invention (including a positive decision on it).