Supplementing Your Diet during Your Pregnancy

By Joanne Stone, Keith Eddleman, Mary Duenwald

If your diet is healthy and balanced, you get most of the vitamins and minerals you need naturally — with the exception of iron, folic acid, and calcium. To make sure you get enough of these nutrients and to guard against inadequate eating habits, your practitioner is likely to recommend prenatal vitamins.

In the case of vitamins, more isn’t necessarily better; take only the prescribed number of pills each day. Several different prenatal vitamins are available, and they are generally equivalent. Some are better tolerated than others, so if you find the one you’re taking is not agreeable to you, try a different brand.

Also, many now contain omega-3 fatty acid supplementation. Some data suggests that omega-3 supplements may decrease the risk of preterm delivery and may have a beneficial effect on the newborn brain, but this hasn’t been proven with certainty.

If you miss taking a vitamin, don’t worry. Nothing bad is going to happen. During the early months, if your vitamins make you nauseous, skipping them until you feel better is perfectly safe for the baby. Remember that the baby is still very small, without large nutritional requirements.

If you’re very early in your pregnancy (four to seven weeks), you can take just a folic acid supplement, which is sometimes easier to tolerate, until you can handle the complete prenatal vitamin pill. If later on in the pregnancy you get a stomach virus and can’t tolerate vitamins for some time, that’s not a problem, either.

The growing baby is able to get what it needs, even at the expense of the mom (a theme that continues throughout life!).

If you find that the vitamins really make you nauseous, try eating a few crackers before you take them, or take them at bedtime.

Iron

You need more iron when you’re expecting because both you and the baby are making new red blood cells every day. On average, you need 30 milligrams (mg) of extra iron every day of your pregnancy, which is what most prenatal vitamins contain.

Blood counts can easily drop during pregnancy because your body gradually is making more and more blood plasma (fluid) and relatively fewer red blood cells (a condition that is called a dilutional anemia). If you do develop anemia, you may need to take an extra iron supplement.

Foods rich in iron include chicken, fish, red meat, green leafy vegetables, and enriched or whole-grain breads and cereals. You can raise the iron content of foods by cooking them in cast-iron pots and skillets.

Calcium and vitamin D

You need about 1,200 milligrams of calcium and 2,000 units of vitamin D every day while you’re pregnant. (The U.S. Recommended Daily Allowance [USRDA] of calcium for all women is about 1,000 mg.) Most women actually get much less.

If you’re already starting out somewhat deficient in calcium and vitamin D, the calcium requirements of the developing baby will only make matters worse for you. A fetus can extract enough calcium from its mother, even if it means getting it at the expense of the mother’s bones. So the extra calcium and vitamin D needed during pregnancy are really aimed at protecting you and your health. The vitamin D helps you store the calcium.

Prenatal vitamins contain only about 200 to 300 mg of calcium (about one-quarter of the USRDA), so you need to get calcium from other sources as well.

Getting enough calcium from your diet alone is possible if you really pay attention. You can get it from three to four servings of calcium-rich foods, such as milk, yogurt, cheese, green leafy vegetables, and canned fish with bones (if your stomach can take it). Supermarkets also stock special lactose-free foods that are high in calcium.

The following list indicates portions of foods that qualify as one serving (300 mg of calcium):

  • 1 8-ounce glass of milk

    Choose low-fat or skim milk.

  • 4 ounces of cooked broccoli

  • 4 to 5 ounces of canned salmon with bones

  • 1-1/2 to 2 ounces of cheese

    Cottage cheese has less calcium than many other cheeses.

  • 8 ounces of yogurt

If your diet is low in calcium, take a supplement. Tums and some other antacids contain quite a bit of calcium and, at the same time, help relieve any pregnancy heartburn you may have. (A single Tums tablet has the equivalent calcium content of an 8-ounce glass of milk.)