There is no real consensus on the ideal nutritional approach to recommend for gestational diabetes (GDM) treatment. A carbohydrates reduction (low-carb) is frequently suggested, although many studies have not found any consistent beneficial effects. On the other hand, according to recent meta-analyses, a low glycemic index (GI) diet would have favorable effects for the mother and the child. Although the clinical and practical value of GI is still being studied, a low GI diet seems to be the most appropriate approach in GDM. In addition, soluble fibers may have a beneficial metabolic impact in the short time of pregnancy. More evidence on the impact of these nutritional approaches in the short and long term for mother and child is needed.