Pregnancy: Essential Nutrition

By Kara Rienzo, R.D.N.

There are many misconceptions that you will not be able to eat vegetarian or vegan while pregnant. Your doctor and perhaps even a dietitian may have told you that you need to give up your plant-based diet during your pregnancy. This advice can lead to even the most committed vegan doubting herself. However, a well-planned vegetarian or vegan diet can meet the needs of both the expectant mother and her unborn baby and enable you to have a healthy and successful pregnancy. Generation Veggie is here to help! Please read the Essential Nutrition pages, check out the Everyday Nutrition for Vegan Kids advice column, chat with other expectant and new parents in the Generation Veggie Forums, and visit our Shop vegan pregnancy books and resources. 

Calorie Needs and Weight Gain                                     

Many women may believe that they need to “eat for two,” but this is not exactly the case. In fact, there is no need to eat additional calories during the first trimester. However, during the second trimester, a woman needs to eat an extra 340 calories a day, and during the third trimester, she needs an extra 450 calories a day [1]. This could vary, based on the woman’s pre-pregnancy weight. If a woman is underweight, based on body mass index (BMI), she may need to consume additional calories, and if she is overweight, she may need to eat fewer calories [2].

Recommended prenatal weight gain based on pre-pregnancy BMI is as follows [3]:

Women pregnant with more than one fetus will need to gain weight to support optimal growth of all fetuses. Women carrying twins are recommended to gain 35-45 pounds during the pregnancy, whereas women pregnant with triplets are recommended to gain 50 pounds [3].

Essential Nutrients

Nutrient needs are great in comparison to calorie needs. It’s important to eat a healthy, well-balanced diet rich in all of the nutrients both the mother and baby need during the pregnancy. Paying special attention to the following nutrients is recommended.

Protein

Vegetarians and vegans are constantly questioned about where they get their protein. The bad news is, they might get asked this question more often during pregnancy. The good news is that it is quite simple to get enough protein with a healthy, varied diet!

Protein is needed in the diet to build new tissue and repair cells. The recommendation for pregnant women is 71 grams daily (which is about 50 percent higher than the recommendation for non-pregnant women) to support the growth of a healthy fetus [1]. Foods high in protein include dried beans and lentils, soy products, nuts and nut butters, whole grains, and some plant-based dairy products.

Omega-3 Fatty Acids (DHA)

Essential fatty acids are important nutrients that are transferred through the placenta to the fetus during pregnancy and are required for normal fetal growth and development, particularly of the brain and eyes [3][4]. Lacto-ovo vegetarians get little DHA in their diets, while vegan diets contain virtually no DHA. This can be taken in microalgae-based supplement form and it is recommended that pregnant women get 300 mg per day; there are several vegan DHA supplements on the market. Foods containing omega-3 fatty acids include foods fortified with algal oil (microalgae-derived DHA), such as Gardein Fishless Filets, Silk DHA Omega-3 Soy Milk, and fortified olive and canola oils.

Iron

This mineral is extremely important, and you should triple your consumption during pregnancy to equal about 48.6mg per day [3]. Not only is iron essential for the increase of maternal red blood cells, but it is also used to accumulate fetal iron stores, necessary for the baby after they are born. If the mom has low blood iron, this can lead to low birth weight or premature delivery [5]. Foods high in iron are beans, green leafy vegetables, iron-fortified cereals, whole grains, dried fruit, and tofu. Eating foods rich in vitamin C, such as bell peppers, citrus fruits, and tomatoes, with high iron foods can help increase the absorption of iron by the body. Foods high in calcium, as well as coffee and tea, can decrease the absorption of iron by the body [2][3][5].

Folate

Folate helps to decrease the risk of certain birth defects of the brain and spinal cord, called neural tube defects. An adequate amount of this vitamin is necessary early in the first month of pregnancy, likely before a woman knows she is even pregnant. Studies have shown that taking a folic acid supplement before becoming pregnant can reduce these defects by 50 percent or more [3]. Recommendations are for women of childbearing age to take a folic acid supplement or eat fortified foods equaling 400μg each day, in addition to eating foods rich in folate equaling 600 μg daily [6]. Foods high in folate include green leafy vegetables, orange juice, wheat germ, enriched, whole grain breads and cereals, and dried beans.

Zinc

Zinc is necessary for tissue growth and function. Women following a plant-based diet may have lower absorption of zinc, so recommendations are higher, at 11mg daily, than omnivores to ensure adequate absorption [7]. Foods high in zinc are tofu, beans, nuts, seeds, fortified cereals, and wheat germ.

Iodine

The body needs iodine to make thyroid hormones, which controls the body’s metabolism. During pregnancy, iodine is especially important, because thyroid hormones allow for proper bone and brain development of the fetus. [8] Iodine can be found in products made from grains and iodized salt.

Calcium

Calcium helps to build strong bones and teeth in the unborn baby. It also plays a role in healthy muscle and nerve function. If a pregnant woman does not get enough dietary calcium for fetal growth, it will pull calcium from the mother’s bones, which can lead to osteoporosis later in her life [9]. The recommended daily intake is the same in both non-pregnant and pregnant women at 1000mg, which is partly due to increased maternal calcium absorption, and is relatively easy to reach [9]. Foods high in calcium include fortified plant-based milks, tofu, low oxalate green leafy vegetables (kale, bok choy, collards, broccoli) soybeans, almonds, figs, and fortified orange juice.

Vitamin B₁₂

Vitamin B₁₂ maintains healthy nerve and red blood cell function. Naturally, vitamin B₁₂ is only found in foods that come from animals, so it is necessary for vegans to take a supplement or eat foods fortified with vitamin B₁₂. Because there is no evidence proving that the mother’s vitamin B₁₂ stores transfer through the placenta, it is very important for vegans to regularly consume products containing B₁₂ [10]. Recommended amounts for women increase only slightly during pregnancy at 2.6μg per day. Good sources of vitamin B₁₂ include fortified cereals, fortified plant-based milks, B₁₂ fortified nutritional yeast, and supplements.

Vitamin D

Vitamin D helps the body use calcium to form fetal bones. Needs are about the same for women both before and during pregnancy, at 600IU per day, but is necessary for both maternal health and fetal development [9]. Vitamin D can be found in fortified cereals, vitamin D fortified plant-based milks, and skin exposure to sunlight.

Fluids

It is recommended to drink 8 to 12 cups of water or other beverages, including caffeine-free or 100 percent fruit juice, throughout the day. Keep in mind that juice and other sweetened beverages can add a lot of extra calories, so try not to drink too much of these. Staying hydrated can help important nutrients get to your unborn baby and also reduce pregnancy-related issues, like constipation and hemorrhoids.

Physical Activity

Healthy women are recommended to do at least 150 minutes a week of moderate intensity aerobic activity, such as brisk walking, to maintain good health and contribute to healthy prenatal weight gain. Women who do vigorous aerobic activity, such as running, can continue this during their pregnancy with approval from their healthcare provider. While pregnant, women should avoid doing any exercise that involves lying on their back, puts them at risk for falling, or has a risk of resulting in abdominal injury [11].

Recommended Amounts of Each Food Group

** Women who have a low pre-pregnancy BMI may have to eat additional servings to achieve adequate prenatal weight gain.**

Sample Daily Meal Plan

Breakfast

• ¾ – 1 cup whole grain cereal topped with ¼ cup of berries and 2 Tbsp chopped walnuts
• 1 cup of plant-based milk
• ¾ cup calcium fortified orange juice

Snack

• 3 cups air popped popcorn sprinkled with 1 tsp of olive oil and 1 Tbsp nutritional yeast
• 1 medium piece of fruit

Lunch

• Sandwich made with:
  • 2 pieces of whole grain bread
  • ½ cup baked tofu
  • 2 slices of tomato
  • 1 tsp vegan mayonnaise
• ½ cup cooked broccoli with ½ cup cooked quinoa

Snack

• 4 whole wheat crackers
• 8 baby carrots
• ¼ cup hummus

Dinner

• ½ cup of rice
• ½ cup of beans
• ½ cup plant-based beef crumbles (e.g. Boca or Gardein)
• ½ cup cooked spinach
• ½ cup cooked red peppers
• 1 cup fortified plant-based milk

References

1. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, D.C.: National Academies Press, 2005.
2. Rasmussen KM, Yaktine AL, eds.; Committee to Reexamine IOM Pregnancy Weight Guidelines, Food and Nutrition Board and Board on Children, Youth, and Families. Weight Gain During Pregnancy: Reexamining the Guidelines. Washington D.C.: National Academies Press, 2009.
3. Byrd-Bredbenner, C., Moe, G., Beshgetoor, D., Berning, J. Wardlaw’s Perspectives in Nutrition, 8^th ed. New York: McGraw-Hill, 2009.
4. Koletzko B, Larque E, Demmelmair H. Placental transfer of long-chain polyunsaturated fatty acids (LC-PUFA). J Perinat Med. 2007;35(suppl):S5-11.
5. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academies Press, 2001.
6. Food and Nutrition Board, Institute of Medicine. Dietary reference intakes for thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B₁₂, pantothenic acid, biotin, and choline. Washington, DC: National Academy Press; 1998.
7. World Health Organization, Food and Agriculture Organization of the United Nations. Vitamin and mineral requirements in human nutrition. 2nd ed. Rome: World Health Organization and Food and Agriculture Organization of the United Nations; 2004.
8. Bowen, R. Thyroid hormones: Pregnancy and fetal development. Retrieved from http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/thyroid/thyroid_preg.html.
9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. Washington, D.C.: National Academies Press, 1997.
10. Allen LH. Vitamin B-12 metabolism and status during pregnancy, lactation, and infancy. Adv Exp Med Biol. 1994;352:173-86.
11. Centers for Disease Control and Prevention. Physical activity for everyone: Healthy pregnant or postpartum women. Retrieved from http://www.cdc.gov/physicalactivity/everyone/guidelines/pregnancy.html