The aim of this study is to evaluate whether nutrients intake in an Italian adult population receiving pharmacological treatment for hypertension, dyslipidemia, and diabetes are within the recommended values proposed by dietary guidelines. Cross-sectional data from the Cardiovascular Epidemiology Observatory/Health Examination Survey in 8462 individuals 35–79 years were used. Food consumption was assessed with a self-administered semi-quantitative food frequency questionnaire. Dietary sodium and potassium intakes were measured in 24-hour urine collection. Recommendations from WHO were used for salt and potassium intakes, those from the Diabetes and Nutrition Study Group for diabetes, and those from the European Society of Cardiology for hypertension and dyslipidemia. Salt intake in urine collection of participants receiving treatment for hypertension was 11.1 ± 4.0 g/day for men and 8.6 ± 3.3 g/day for women, higher than recommended. In participants treated for dyslipidemia, mean saturated fat intake was 11.4% and 11.6% total Kcal in men and women respectively, higher than recommended, while cholesterol intake was higher only in men (365.9 ± 149.6 mg/day). In both men and women receiving treatment for diabetes, mean intake of saturated fats (12.3% and 12.2% of total Kcal), simple carbohydrates (17.5% and 19.8% of total Kcal) and cholesterol (411.0 ± 150.4 and 322.7 ± 111.1 mg/day) were above the recommendations, while fiber intake was below (19.5 ± 6.3 and 17.5 ± 6.2 mg/day). Overall, 70% to 80% of participants treated for these conditions received advice from family doctors on dietary management; however, nutrition is far from being optimal.