Eating for Two: Nutrition during Pregnancy

Prudence Athearn Levy, MS, RDN, LDN 

Pregnancy is such an exciting time in our lives. I loved and cherished both of my pregnancies, both at the time, and thinking back now, to that new, full of possibility brief moment in time, both scary and exciting, and for me resulting in two, so different, but each incredible, brilliant, loving and lovable boys. Each pregnancy was so different for me, in what it meant, how I felt, and what I was capable of accomplishing, but equally magical in their own ways.  For many of us, myself included, it is the time when we are most diligent with our health goals, knowing intuitively that our life choices directly affect the little one growing inside us. 

Sometimes though, it can also be overwhelming, worrying whether what we are doing is the best thing for baby, or reading and hearing conflicting information - especially about what we should and shouldn’t eat while pregnant. Rest assured, if you are taking care of your body, staying hydrated, eating enough to gain some weight but not too much unnecessary weight, exercising if you are able, and not smoking or engaging in other harmful activities, your baby should grow just as he or she should. That said, paying closer attention to your nutrition during pregnancy can help you have an easier, happier pregnancy, better birth experience, healthier baby, and make it easier to return to pre-pregnancy weight.

Pregnancy and breastfeeding are the only times in our lives that what we eat (or don’t eat) actually does affect someone else directly - baby! The phrase “eating for two” is correct in this sense, but your calorie needs don’t actually increase that much. In fact, during your first trimester you don’t need to consume any more calories than you used to (as long as you were meeting your nutrition needs and not underweight before pregnancy). After that, you’ll need to consume about 300 extra calories per day during your second and third trimesters- about what you would get by eating an extra snack of a banana with 2 tablespoons of almond butter. Gaining too much weight can make pregnancy, delivery and returning to pre-pregnancy weight more difficult, is linked with obesity later in life, and increases your risk for pre-eclampsia, pregnancy induced hypertension (PIH), and gestational diabetes. That said, it is equally important to remember that pregnancy is not a time for weight loss or restrictive eating. Gaining too little weight increases your risk for a premature birth, and/or having a low birth weight infant (with greater risk for developmental difficulties and other health problems).  It’s important to follow your obstetrician’s recommendation for weight gain that is right for you specifically. And remember, a healthy pregnancy does include some fat storage- you’ll need this during both labor and when breastfeeding your baby. Most of your weight gain goes to increases in blood volume (your blood volume increases by up to 60%!), increases in your uterus and breast size, placenta weight, overall fluid volume and amniotic fluid, and of course the size of your growing baby!

When I’m working with a pregnant mom to help her optimize her nutrition, we go through her specific needs for nutrients, and how she can plan her meals to get those through food. Here, I’d like to give you a general sense of which nutrients are most important to pay attention to getting through food during pregnancy, and give you some ideas to help you make the most of your pregnancy nutritionally!

Most women know it is important to eat a varied diet rich in fruits, vegetables, whole grains, calcium-rich dairy or dairy alternatives, lean meats or vegetarian sources of protein (i.e. legumes, organic soy), nuts and seeds, and healthy fats. But now you have specific and/or increased needs for calories and protein, along with the micronutrients iron, vitamin C, folate (folic acid), vitamins B6 and B12, zinc, calcium, vitamins D and A, iodine, choline, and DHA (an omega-3 fat). Water/fluid needs increase as well, generally by 2-4 cups/day, and I usually recommend aiming for between 64 to 96 ounces each day.  By getting these necessary nutrients through food and pure water (in addition to your prenatal vitamin, if recommended by your nutritionist and/or doctor), you’ll be maximizing the nutrition your baby receives.

One of the most important nutrients, omega-3s (especially DHA) serve key functions during pregnancy. They make up almost half the structure of the human brain, and are essential when the fetal brain is forming. Omega-3 intake during pregnancy is also associated with improvements in your mood and memory, which is a double incentive for finding safe sources of omega 3s to consume. Fatty fishes are the best source of DHA, but some can be too high in mercury or PCBs to safely consume regularly. Be sure to avoid shark, swordfish, king mackerel and tilefish, and limit your bluefish intake to only the lighter flesh and no more than 6 oz/week. Wild salmon is a great choice, and we can safely have two servings per week (up to 12 ounces). I do recommend choosing wild salmon whenever possible, but another option is exclusively organically farmed fish. Faroe Islands salmon is another sustainable farmed choice.  You can also get your DHA through canned light tuna (I recommend buying canned light tuna only from companies that both use smaller fish and test for mercury and PCBs such as Wild Planet). Many other varieties of fish are also considered safe during pregnancy, and help you meet your increased protein needs as well, such as flounder, sole, haddock, cod, tilapia, and halibut. If you don’t eat high omega-3 fish, I recommend a pure and third-party tested supplement of 300 to 500 mg DHA per day throughout pregnancy and breastfeeding, as it is very difficult to get enough usable DHA through vegetarian sources such as flaxseed.

Eating for two also means you need to pay extra attention to protein. Your developing fetus needs extra protein, one place in particular: structural development of the placenta. Approximately 950 g of protein are synthesized for your fetus and placenta. Usually an extra 10-20 grams/day will meet your needs, and I typically recommend a total of 80-100 g/day to optimize fetal development. Great sources of protein are plentiful: poultry, fish, shellfish, eggs, beans, lentils, beef, pork, tofu, tempeh, edamame, nuts, seeds, and organic or growth hormone-free dairy foods are all high in protein. For reference, a 4 ounce serving (the size of deck of cards) of meat or fish yields 28 grams of protein, two eggs are 12 grams, 1 cup of Greek yogurt is about 23 grams, and ½ cup of beans or 2 tablespoons of nut butter give you 8 grams of protein.

While you have increased needs for the majority of the vitamins and minerals listed above, and each are each essential for proper growth and development of your baby, you will get most of these when you eat a varied diet including lots of fruits and vegetables, nuts and legumes. If salads and steamed vegetables make you gag (like they did for me during my first pregnancy- shocking as they are usually my favorite foods!), try incorporating them into smoothies, soups or egg dishes to make them more palatable. Or, you may do better with raw vs. cooked vegetables, or vice versa. Don’t stress if you just can’t eat a lot of vegetables- you can use fruits and nuts and seeds to get many of the same nutrients, in addition to a good prenatal vitamin for extra folate. Similarly, if beans and lentils turn you off, try blending them and sneaking them into your quesadillas or pasta sauce. And if you can’t tolerate dairy during pregnancy, make sure you are getting enough calcium through leafy greens, beans and lentils, and/or fortified plant-based milks. Getting enough calcium may help you stave off leg cramps, and preserves your own stores of calcium while baby takes what he or she needs for the formation of bones and teeth.

Iron is another key mineral worth mentioning on its own. Your needs increase from 18 mg/day to 27 mg/day! Most women choose to ensure they are meeting this increase by taking a prentatal vitamin with iron, but you can also reach this by consuming a targeted amount of green, leafy vegetables, lean meat and poultry, legumes, organic soy, and whole grains. Another key nutrient that most women know that we need more of is folic acid, but even if your prenatal vitamin has the recommended dose (800 mcg), I recommend getting at least 200 mcg from folate-rich food sources such as citrus fruits and juices, and the aforementioned dark-green leafy vegetables, nuts, and legumes and whole grains. And finally, the last nutrient I’ll mention here specifically (because our needs increase by almost 50% for fetal cell growth and brain development) is zinc. You’ll meet your increased zinc needs by including meat, fish, dairy and/or eggs in your diet daily. If you are vegetarian, you might want to consider a prenatal with added zinc, as vegetarian sources (ie whole grains, wheat germ, black eyed peas and miso) have less absorbable zinc.

There is so much you can do to ensure a healthy pregnancy, and optimizing your nutrition is just one of the things you can do to feel your best. So eat well, relax, sleep, stretch, move often, and enjoy this amazing and powerful time in your life!

Prudence Athearn Levy earned her Masters’ degree in Human Nutrition from Colorado State University in 2003, and completed her internship and credentialing in 2004. She provides nutrition therapy and counseling in all areas of nutrition, specializing in diabetes, weight, eating disorders, maternity, postpartum, childhood nutrition, cardiovascular health, GI health, and food allergies.