BackgroundUniversity students are often affected by food insecurity (FI) and this situation has been associated with low consumption of fruit/vegetables and high intake of added sugars and sweet drinks. However, there needs to be more evidence on the association between FI and dietary patterns (DPs), assessing the overall diet and allowing analysis of commonly consumed food combinations. We aimed to analyze the association between FI and DPs in university students’ households.MethodsWe used data from 7659 university student households from the 2018 Mexican National Household Income and Expenditure Survey (ENIGH, for its acronym in Spanish). We obtained FI levels (mild, moderate, and severe) using the validated Mexican Food Security Scale (EMSA, Spanish acronym). Two DPs were identified by principal component analysis based on the weekly frequency of consumption of 12 food groups. Multivariate logistic regression adjusted by university student and household’s characteristics was applied.ResultsCompared to food security, households with mild-FI (OR:0.34; 95%CI:0.30, 0.40), moderate-FI (OR:0.20; 95%CI:0.16, 0.24) or severe-FI (OR:0.14; 95%CI:0.11, 0.19) were less likely to adhere to the dietary pattern “Fruits, vegetables and foods rich in animal protein” (fruits, vegetables, meat, fish or seafood, dairy products, and starchy vegetables). In addition, people with severe-FI (OR:0.51; 95% CI:0.34, 0.76) were also less likely to adhere to the dietary pattern “Traditional-Westernized” (pulses, oils or fats, sugar, sweets, industrialized drinks, foods made from corn/maize, wheat, rice, oats or bran, coffee, tea and eggs).ConclusionsIn these households FI impairs the ability to consume a healthy dietary pattern (fruits/vegetables and foods rich in animal protein). In addition, the intake of foods typical of the Mexican food culture reflecting the local Western dietary pattern is compromised in households with severe-FI.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12889-023-15755-z.