This study analyses the nutritional value of diets of girls who follow three different food patterns, expressed as different frequencies of consuming alcohols, legumes, fish, beef, margarine and butter. One hundred and seventy-eight girls, aged 15-18 years from secondary schools of various types situated in the Suwałki region and in the city of Olsztyn were included in the study. Factor analysis was applied to the information about the frequency of consuming 21 products, which resulted in identifying 8 food patterns typical of young people. Three selected food patterns were further analysed. These were: alcohol (food pattern II), legumes, fish and beef (food pattern V) and margarine (food pattern VII). None of the food patterns analysed in this study had the correct nutritional value or pro-health characteristics. An increase in the frequency of consuming legumes, fish and beef, an increase in the frequency of consuming alcohol or an increase in the frequency of consuming margarine with a concurrent decrease in the frequency of consuming butter, resulted in reduction of the amounts of many vitamins, minerals and fibre in the girls’ diets. A growing frequency of alcohol consumption was accompanied by other undesired eating habits, such as an increasing consumption of high fat snacks or a decrease in the consumption of low fat meat products and wholemeal bread. As the frequency of consuming margarine increased, the energy value of the diet decreased, and the drop in the frequency of legumes, fish and beef consumption was associated with the reduction of fat and, paradoxically, PUFA in the diet. The results indicate that an increase in the frequency of consuming alcohols, legumes, fish, beef and margarine resulted in decreasing the nutritional value of the girls’ diets and was caused by their being less varied.