Patients suffering from mental disorders – particularly schizophrenia, bipolar disorder, and depression – are at least 1.5 times more likely to develop metabolic disorders than the general population, with prevalence among people with mental disorders exceeding 30%. In 2019, the Polish Psychiatric Association (PTP) developed and published recommendations on reducing metabolic risk in patients with schizophrenia treated with antipsychotics (APs). This article presents the first part of the update and expansion of these recommendations. It focuses on risk factors for obesity, diabetes, and metabolic disorders in people treated with APs, as well as guidelines on non-pharmacological interventions to prevent and treat metabolic disorders. The recommendations were prepared by a group of experts invited by the Board of PTP based on a literature review, analysis of published guidelines, and clinical experience. Psychiatrists should not only be aware of the increased risk of metabolic disorders in people treated with APs but should also actively act to prevent these conditions. The basis of prevention is lifestyle modification through small, gradual steps easier to maintain over the long term. Recommended interventions include: (1) nutritional education, (2) regular physical activity, (3) meal planning, (4) menu preparation, (5) mindfulness and relaxation techniques, (6) participation in support groups, (7) progress monitoring. In cases of high risk, or when such disorders are already present, pharmacological interventions are recommended, as outlined in the second part of the guidelines.