You already know that eating for two doesn't mean simply eating more: It means you need more of specific nutrients that help keep you healthy and aid in the development of your baby. A good way to start: Aim for plenty of fruits, vegetables, whole grains, and lean protein. Certain prenatal nutrients are also key.
Where to get it: cold-water fish, like salmon (choose wild over farmed), trout, and sardines; and fortified foods, like eggs and milk. Because DHA is beneficial both in the womb as a baby develops and after a baby is born, this nutrient is found in prenatal supplements and breast-feeding supplements, as well as in infant formulas. Just be sure to check the label—not all supplements and formulas contain expert-recommended levels of DHA (200 milligrams daily while pregnant or breastfeeding).
Where to get it: fortified cereals; leafy green vegetables, like spinach; citrus fruits, like oranges; and dried beans. While it's important to eat a healthful diet, taking a prenatal supplement with folic acid is recommended so that you're getting everything you need. Ideally, you'll start taking your prenatal supplement three months before you try to conceive, but if you're not already taking one, now is a good time to start.
Also talk to your doctor about other important prenatal nutrients, such as calcium (for strong bones) and iron (for motor, mental, and immune development).