Can a high carb - low fat diet cause water retention even though on a caloric deficit? its weird i gained 6 pounds in the first 3 days!!!!

Salt intake?: Too much salt in the diet will result in increased thirst and fluid retention, and fluid retention can lead to weight gain despite a calorie deficit. Some medications are also associated with weight gain. High carb, low fat diet without with calorie deficit and without excess sodium should not cause weight gain or fluid retention.