Absolutely not. Mustard spinach are greens that come loaded with several essential nutrients. Folate, an essential nutrient during pregnancy, is present in good amounts in mustard spinach, preventing neural tube defects, such as spina bifida, in the newborn baby. Mustard spinach is also a good source of Vitamin C, which boosts the immunity of both the mother and the baby. Calcium in mustard spinach helps in the development of teeth and bones of the developing baby.