Background Multidisciplinary heart failure (HF) programs reduce hospital readmission and improve clinical outcomes. Although dietitians are often members of such teams, no randomized studies have demonstrated the independent benefit of dietitian-administered dietary counseling for patients with HF. The purpose of this study was to evaluate the effect of dietitian education on adherence to a sodium-restricted diet in ambulatory patients with stable HF. Methods Patients with HF (left ventricular ejection fraction <35%) were randomized into a dietitian education group (n = 23) or a usual care group (n = 24), then observed for 3 months. Both groups received a 2 g/d dietary sodium prescription. The usual care group received nutrition advice by way of self-help literature, whereas the dietitian education group returned for 2 counseling sessions with a dietitian. Results Dietitian education resulted in a significant decrease in sodium intake at 3 months (2.80 +/- 0.30 to 2.14 +/- 0.23 g/d, P < 05). In contrast, there was no change in sodium intake in the usual care group (3.00 +/- 0.31 to 2.74 +/- 0.35 g/d, P = ns). Conclusions Dietitian-administered counseling was more effective than providing literature in reducing dietary sodium intake in patients with stable HF.