AbstractObjectiveHealthy lifestyle habits are the cornerstone in the management of familial hypercholesterolaemia (FH). Nevertheless, dietary studies on FH-affected populations are scarce. The present study analyses dietary habits, adherence to a Mediterranean diet pattern and physical activity in an adult population with FH and compares them with their non-affected relatives.DesignCross-sectional study.SettingData came from SAFEHEART, a nationwide study in Spain.ParticipantsIndividuals (n 3714) aged ≥18 years with a genetic diagnosis of FH (n2736) and their non-affected relatives (n 978). Food consumption was evaluated using a validated FFQ.ResultsTotal energy intake was lower in FH patients v. non-affected relatives (P<0·005). Percentage of energy from fats was also lower in the FH population (35 % in men, 36 % in women) v. those non-affected (38 % in both sexes, P<0·005), due to the lower consumption of saturated fats (12·1 % in FH patients, 13·2 % in non-affected, P<0·005). Consumption of sugars was lower in FH patients v. non-affected relatives (P<0·05). Consumption of vegetables, fish and skimmed milk was higher in the FH population (P<0·005). Patients with FH showed greater adherence to a Mediterranean diet pattern v. non-affected relatives (P<0·005). Active smoking was lower and moderate physical activity was higher in people with FH, especially women (P<0·005).ConclusionsAdult patients with FH report healthier lifestyles than their non-affected family members. They eat a healthier diet, perform more physical activity and smoke less. However, this patient group’s consumption of saturated fats and sugars still exceeds guidelines.