Barker’s thrifty phenotype hypothesis suggests a relationship between low birth weight and obesity, type 2 diabetes mellitus and atherosclerosis in later life. Aim: The aim of the study was to assess the nutritional status and the incidence of selected atherosclerotic risk factors among people in their third decade of life in relation to their birth weight and term of delivery. Material and methods: A total of 119 subjects aged between 19 and 29 years were classified into the following groups: born prematurely (group I – 38 subjects), born at term, but with low birth weight (group II – 39 subjects), and born at term with normal birth weight (group C – 42 subjects) as well as into groups with birth weight <10^th percentile and ≥10^th percentile for gestational age. We analysed sociodemographic data on health behaviours and the health status of both participants and their parents. Body weight and height, waist and hip circumferences as well as blood pressure were measured. Additionally, body composition was estimated by bioelectrical impedance analysis. Glucose, cholesterol and triglyceride levels were determined using strip tests. Results: Significantly higher mean levels of cholesterol, a significantly higher prevalence of increased cholesterol and a non-significant increase in the prevalence of obesity, including abdominal obesity, were found in group I compared to other groups. A non-significant increase in the prevalence of abdominal obesity and a higher proportion of adipose tissue compared to controls as well as significantly the lowest prevalence of hypercholesterolaemia were observed on group II. A positive correlation was observed between the body mass index in those born prematurely and the body mass index of their mothers. Among the independent variables affecting the number of atherosclerotic risk factors, the importance of premature birth, age and excessive parental nutritional status was confirmed. Conclusions: 1) Premature birth increases the risk of elevated serum cholesterol levels in the third decade of life. 2) Premature birth and intrauterine growth restriction do not increase the risk of obesity in the third decade of life. 3) Premature birth, increasing age and excessive parental nutritional status have an impact on the number of atherosclerotic risk factors in the third decade of life.