Purpose: Changes were examined in energy intakes and percentage of energy from macronutrients in response to nutritional intervention in women with gestational diabetes mellitus (GDM). Methods: The study included 17 women with GDM and 27 women with normal glucose tolerance (controls). Women with GDM were followed by a multidisciplinary team; they received dietary counselling by a registered dietitian, and were prescribed diets with 40% to 45% energy from carbohydrate (CHO), 20% to 25% from protein, and 30% to 35% from fat. Dietary intakes were assessed with food frequency questionnaires before the intervention (26.9 ± 3.8 weeks) and after the intervention (32.6 ± 0.6 weeks). Results: After the intervention, women with GDM reduced their total energy intake to reach lower values than did controls (P value for time-group interaction ≤0.05). A concomitant reduction in total CHO and glucose intakes in women with GDM led to significantly lower values compared with intakes in controls (P values for time-group interaction ≤0.001 for all). The post-intervention rate of weight gain in women with GDM was within the Institute of Medicine (IOM)-recommended values, while the post-intervention rate of weight gain in controls was above IOM-recommended values (0.30 ± 0.27 versus 0.61 ± 0.50 kg/week, P≤0.05). Conclusions: These results suggest that this multidisciplinary medical and nutritional intervention was effective in the achievement of prescribed macronutrient distribution and controlling gestational weight gain in Canadian women with GDM.