While pregnant, you may be tempted to give in to those cravings for pickles and ice cream — and that's fine, if done occasionally. But keep in mind that everything you eat during your pregnancy affects your growing baby.
During pregnancy, you are your baby's only source of nourishment. Every nutrient that your baby needs must be eaten by you. Only you can make sure that your baby receives the best quality food. And you need to know which foods will provide the proper nutrition for your growing baby.
Adequate energy intake is important for the growth and development of the fetus and for the mother's ability to adapt to stresses such as infections or episodes of bleeding. Additional energy during pregnancy is required for the production of new fetal and maternal tissues, the additional metabolism the new tissues require, and the increased energy demanded to move the additional body mass during physical activity. Since the body mass of a woman increases about 20% during pregnancy, work involving a lot of movement will use 20% more energy. Given these considerations, the total caloric cost of pregnancy has been calculated to be about 80,000 calories — 300 calories per day. A further adjustment of energy requirement should be based on physical activity. Since energy expenditure varies so widely, the best index of adequate intake is a satisfactory weight gain.
This relatively small increment in calories per day is critical to a healthy pregnancy. The extra calories required per day is approximately equal to 1 cup of ice cream or a bagel with cream cheese. The calorie increase in the first half of pregnancy will result in an increase in maternal fat. The fat deposited represents important energy reserves that can support increased energy demands on the part of the rapidly growing fetus in the latter third of the pregnancy. The calories in the second half of the pregnancy will support your increased requirements for metabolism, your physical activity, as well as the rapid growth of the fetus.
Protein is one of the most important nutrients for pregnant women because it provides the growth element for body tissues — including the growing baby, the placenta, the increase in the mother's blood volume and the amniotic fluid. During pregnancy, a total of three to four servings a day is recommended. Lean meats, eggs and other foods such as beans and tofu are excellent sources of protein. Fish is also a good source of protein and other nutrients, but fish contains mercury, which can be particularly harmful to the nervous system of a developing fetus. Because of that fact, pregnant women should limit the amount and kind of fish they eat.
The Environmental Protection Agency and the U.S. Food and Drug Administration suggest women follow these three guidelines:
- Do not eat shark, swordfish, king mackerel or tile fish. These fish contain high levels of mercury.
- Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury.
- The five most commonly eaten fish that are low in mercury are shrimp, canned light tuna, salmon, pollock and catfish.
- Another commonly eaten fish, albacore ("white") tuna has more mercury than canned light tuna. So when choosing your two meals of fish and shellfish, limit your intake of albacore tuna to 6 ounces (2 average meal).
- Check local advisories about the safety of fish caught by family or friends in your local lakes, rivers and coastal areas. If no advice is available, you can eat up to 6 ounces (1 average meal) per week of fish you catch from local waters, but don't consume any other fish during that week.
Complex new tissues are produced during pregnancy at a rate greater than at any other time during a woman's life. Protein is essential for this purpose, but during pregnancy, protein requirements cannot be separated from needs for calories and other nutrients. As energy needs take first priority in metabolism during pregnancy, protein will be used for energy if carbohydrates and fat are not consumed in sufficient amounts. It is recommended that pregnant women consume 70 grams of protein per day. This is about 25 grams more per day than non-pregnant women; the equivalent of 2 cups (16 ounces) of milk and 1 ounce of cheese or 3 ounces of meat. Specific dietary modification rarely will be necessary to meet this increase, since most Americans consume far more than the recommended level of protein.
Carbohydrates should provide the largest part of your daily calorie intake. These foods provide the body's main source of energy. There are two types of carbohydrates: simple or refined sugars and complex carbohydrates or whole, intact grains.
Refined carbohydrates like glucose are ready to be used by the body immediately and provide "instant energy." Examples include table sugar, honey, syrup, fruit juices and hard candies (which may be helpful in case of nausea). These are of no nutritional value and add only calories to our diet.
Complex carbohydrates consist of whole grains, potatoes, lentils, beans and peas. The body has to break them down into simple carbohydrates before it can use them, so they provide a steady supply of energy over a period of time. Foods rich in starch also provide fiber, which speeds digestion and helps keeps you "regular."
Calcium, which fortifies your bones and teeth, is found primarily in milk and milk products, although broccoli and canned fish also are good sources. Since most pregnant woman consume only 75% of recommended calcium levels, you may need to deliberately increase the amount of calcium-rich food in your diet. Cheese, milk, yogurt and ice cream are good sources of calcium. If you are lactose (milk sugar) intolerant, green leafy vegetables, tofu, canned salmon and sardines (with bones) are good calcium-rich foods. Foods fortified with calcium can be added to the diet, such as calcium-fortified orange juice. Pregnant women are advised to consume four servings of calcium rich foods per day. Many women may not meet their calcium needs through diet alone. Calcium supplementation may be advised during pregnancy.
The iron requirement doubles during pregnancy from 15 to 30 milligrams per day. Mother and fetus both require additional iron, due to increased maternal blood volume and fetal iron storage to support postnatal requirements. Red meat; whole grain, enriched breads and cereals; and leafy vegetables are sources for iron in the diet. Iron from meat is more efficiently absorbed. When iron-rich food is consumed with food that is rich in vitamin C, absorption of iron is enhanced.
Folic acid has been identified as an important water-soluble vitamin impacting cell development in the embryo and fetus. Low levels of folic acid have been associated with neural tube defects and other adverse pregnancy outcomes. Research suggests that folic acid supplementation during the weeks leading up to and following conception may help prevent neural tube defects.
The U.S. Public Health Service recommends that all women be advised that daily folic acid supplementation of 400 micrograms (0.4 milligrams) may be protective in preventing this problem. Since low levels of folic acid can affect the embryo early in the pregnancy, women planning to conceive should try to consume foods rich in folic acid. This includes deep green leafy vegetables, legumes (lentils, chick peas, black beans, black-eyed peas), orange juice, and whole-grain breads and cereals. The intake of a variety of foods from all the major food groups can, for most women, meet their nutrient requirements for pregnancy. Women with a history of a previous pregnancy with neural tube defects are advised to take a therapeutic dose 10 times that amount or 4 mg, which will require a prescription from your physician.
Vitamins are essential for the overall health of both mother and child. Vegetables and fruits are good sources of many vitamins. Some are rich in vitamin C and others contain vitamins A, B, E, minerals and folic acid. Although some B vitamins are supplied by vegetables and fruit, the bulk of our vitamin B intake is usually supplied by meat, fish, dairy products, grains and nuts. By eating sensibly during your pregnancy, you will usually get all the vitamins and nutrients (except for iron, folic acid and calcium) you need. However, if your doctor thinks your diet may not be supplying all the nutrients you and your fetus need, he may prescribe a prenatal vitamin and mineral supplement. It is very important, however, not to take megadoses of vitamins, as too much of some vitamins (like vitamin A) can cause birth defects.
Fluids and salt
During pregnancy, your blood volume and blood fluids will expand by nearly half, so it's very important to keep up your fluid intake. The recommended daily intake of eight to 10 glasses can be met by drinking water, juice or milk. If you suffer from mild swelling of the ankles, face or fingers, it will not help to limit your fluid intake. While salt should not be overused, it should not be restricted during pregnancy. A moderate salt intake is important for a pregnant woman.
Caffeine during pregnancy has been controversial. Some studies suggest that drinking large amounts of caffeine (found in tea, coffee, soft drinks and chocolate) may cause such problems as miscarriage, fetal death and stillbirth, or can retard fetal growth and induce behavioral abnormalities. But those studies are for five or more cups of coffee a day. Smaller amounts of caffeine — 10 ounces or 300 mg caffeine — appear to be safe during pregnancy. You should check with your doctor about your caffeine consumption.
Dietary guidelines and a healthy diet
Pregnancy is nutritionally demanding. The appropriate supply of nutrients is necessary to support rapid cell division and tissue growth. Remember, a sound diet during pregnancy is only an extension of good usual dietary practices. The diet should reflect a variety of foods and a balanced selection. Relax and enjoy your favorite food while paying attention to overall requirements.
|Protein:||70 g||Meat, fish, poultry, eggs, milk, milk products, legumes, and nuts and seeds|
|Calcium:||1,200 mg||Milk, yogurt, cheese, leafy green vegetables, firm tofu, canned salmon, calcium-fortified orange juice and almonds|
|Iron:||30 mg||Meats, fish, poultry, whole-grain and enriched cereals and breads, legumes, leafy green vegetables, molasses, dried prunes, apricots and raisins|
|600 mcg||Leafy green vegetables, legumes, whole grains, orange juice and assorted vegetables (ie, asparagus)|
|1.9 mg||Wheat germ, meat, whole grains, broccoli, banana, avocado, peanuts, sunflower seeds, soybeans and corn|
|Zinc:||15 mg||Same as iron, plus oysters, wheat germ and brown rice|
Avoid cigarette smoking and other tobacco use
The proportion of pregnant women who smoke is declining but still represents an important problem during pregnancy. Maternal smoking during pregnancy results in a reduction in birth weight of approximately one-half pound. It is the most important modifiable factor responsible for fetal growth retardation. It may also increase the risk of a preterm birth.
First described in 1973, fetal alcohol syndrome is now recognized to affect one to two infants per 1,000 live births in the United States. Although the syndrome is thought to be limited to chronic alcohol abusers, fetal growth retardation has been observed at lower levels of alcohol consumption (1 or 2 ounces of absolute alcohol consumption.) While the evidence of the impact on the fetus of low levels of alcohol consumption remain inconsistent, it is wise to eliminate alcohol intake during pregnancy.