Gestational diabetes diet involves managing carbohydrate, fat, and protein intake to control blood sugar levels during pregnancy. Carbohydrates from fruits, vegetables, and grains impact blood sugar the most so these foods need to be monitored. Protein from meat, eggs, beans, and nuts is important but should be chosen carefully. Fat intake also needs to be controlled, with healthier fats like olive oil preferred over processed fats. Managing these macronutrients can help prevent complications for both mother and baby.