Abstract
The paper presents the designs and methods of a cross-sectional study of two groups of randomly selected Polish inhabitants aged 19-64, and 65 and over, carried out as part of the National Health Program. The aim of the study was to illustrate the current health situation of the respondents in terms of nutrition and physical activity level. The quantitative and qualitative methods were used. The Computer Assisted Personal Interview technique was used. The dietary research was carried out through repeated interviews about the frequency of food consumption, and about what food had been consumed in the previous 24 h. In addition to the questionnaire studies, anthropometric data, blood pressure and the level of physical activity were measured. During the COVID-19 pandemic, some methods were modified according to hygiene rules. The Computer Assisted Telephone Interview technique was used to collect the data, and the anthropometric data were obtained via measurements made by the respondents themselves based on detailed instructions. The results will be used to present representative data for the Polish population, describing a wide range of eating behaviours and other lifestyle elements, food and nutrition knowledge, dietary supplement use, the occurrence of diet-related diseases, nutritional status and, in the seniors group, the risk of sarcopenia.