Few studies have investigated dietary patterns among French adults. We aimed to identify dietary patterns and their relation with nutrient intakes, sociodemographic, lifestyle and other health indicators in a large population of middle-aged subjects living in France. Dietary patterns were identified using factor analysis in 5194 women and men aged 45-60 years enrolled in the SU.VI.MAX (Supplémentation en Vitamines et Minéraux Antioxydants) study. Dietary data were based on repeated 24-h dietary records (at least six records during 2 years). Four patterns were identified: (1) 'alcohol and meat products'; (2) 'prudent diet'; (3) 'convenience foods'; and (4) 'starch, sauces, and vegetables'. The first pattern was positively associated with low education, smoking and overweight in both genders, as well as with abdominal obesity in women and treated hyperlipidaemia and/or hypertension in men. The second pattern was positively correlated with high education and being older than 55 years and negatively correlated with current smoking. This pattern was also associated with overweight and low waist circumference in women and with hyperlipidaemia treatment in men. The third pattern was inversely related to age and positively related to higher education in both genders. In men, higher scores were related to living alone and an urban residence. The fourth pattern was associated with high education and an urban residence in men only. Our study identified four dietary patterns in this population of French middle-aged adults. Associations with sociodemographic, behavioural and health-related factors were found to differ according to dietary patterns. Sex-specific relationships were also found.