Salt is a nutrient that is needed daily by all humans. It is most important for proper cell maintenance andd creation and therefore is a critical nutrient in the diet of a pregnant woman. As a pregnancy progresses, a womans body will make additional blood (about 40 50% more) in order to ensure adequate oxygenation and nutrition of the unborn baby. To do this, the body must retain additional fluid and one of the properties of salt is fluid retention. If salt is restricted during pregnancy, this additional blood volume may not be made and the nutritional needs of the unborn baby will not be met. This may occur because the placentas growth is retarded or stopped or it may even peel off of the uterine wall.

The unborn baby is not the only one to suffer from too little salt. The pregnant woman will be more prone to hypertension, toxemia and other nutritionally derived diseases. Women who are put on low salt diets in the mistaken belief that this will keep them from retaining fluid and swelling, or keep their blood pressure down frequently become more edemic, rapidly gain weight from the water retention and find their blood pressures soaring. These are normal body responses to a salt deficiency and a coping mechanism to restore the necessary balance in the system.

When a woman meets her daily salt need by salting to taste, her body retains the correct amount of fluid to meet its needs and the excess salt is removed from the body via the kidneys. Edema in well-nourished women is not pathologic and may, in fact, have some benefits for the mother and baby.