Pregnancy and the Vegan Diet

by Reed Mangels, PhD, RD
From Simply Vegan 5th Edition

"My doctor says I have to drink a quart of cow’s milk a day; my parents are convinced I’m doing something harmful; and I’m even starting to wonder if my diet is all right." Even the most committed and knowledgeable vegan may face doubts when pregnant. After all, the so-called experts are all questioning her dietary choices.

Actually, it is reasonably simple to follow a vegan diet throughout pregnancy while eating foods that meet your needs and the needs of your baby. A series of studies 1,2 at The Farm, a community where vegan diets are a part of a socially responsible lifestyle, have shown that vegans can have healthy pregnancies and healthy children. Here are some things to consider.

Weight Gain

How much weight you gain during your pregnancy has a marked impact on the baby’s size and health at birth. Table 14 will help you to calculate how much weight you should gain. If you were underweight prior to your pregnancy, you should try to gain 28-40 pounds. Average weight women should aim for a 25-35 pound weight gain, and overweight women should strive to gain 15-25 pounds. Adolescents may need to gain 30-45 pounds. A general trend is to have little weight gain for the first 12 weeks. Then, in the second and third trimesters, a WEIGHT GAin of a pound a week is common 3.

Many vegans begin pregnancy on the slim side and may gain weight very slowly. If this sounds like you, you will need to eat more food. Perhaps eating more often or eating foods higher in fat and lower in bulk will help. I found it easiest to drink extra calories and treated myself to a soy milk shake (soy milk blended with fruit and tofu or soy yogurt) in the evening for a few weeks when weight gain was low. Other concentrated sources of calories include nuts and nut butters, dried fruits, soy products, and bean dips. Table 15 shows some ways of getting some extra calories — you need about 340 extra calories per day in the second and 450 calories per day in the third trimester. If, on the other hand, your weight gain seems too high to you and your health care provider, look at the types of food you are eating. Simply replacing sweets and fatty foods with fruits, vegetables, grains, and legumes can lead to more moderate weight gain. Daily exercise, as approved by your health care provider, can also help.

Table 14: Body Mass Index

Step 1. Take your prepregnant weight (in pounds) and divide it by your height (in inches) squared; then multiply by 700. BMI = lb/in2 x 700. For example, if I weigh 110 pounds and am 60 inches tall, my BMI is 110/3600 x 700 = 21.4.

Step 2. Use your BMI to find your pre-pregnancy weight-for-height status and the amount of weight you should try to gain in pregnancy.

Pre-pregnancy BMI Weight-for-height status Recommended weight gain
<18.5 Underweight 28-40 pounds
18.5 to 24.9 Normal weight 25-35 pounds
25 to 29.9 Overweight 15-25 pounds
>30 Obese 11-20 pounds

Adapted from reference 3.

Protein

You will probably get lots of questions about whether or not you are getting enough protein. Current recommendations for protein in pregnancy call for 25 grams more of protein per day in the second and third tri-mesters for a total of 71 grams of protein 4. One study showed that the average non-pregnant vegan woman was eating 65 grams of protein daily 5, almost enough to meet the needs during pregnancy. If your diet is varied and contains good protein sources such as soy products, beans, and grains, and you are gaining weight, you can relax and not worry about getting enough protein. Many women simply get the extra protein they need by eating more of the foods they usually eat. As an example, you can add 25 grams of protein to your usual diet by adding 1-1/2 cups of lentils or tofu, 3-1/2 cups of soy milk, or 2 large bagels.

Calcium and Vitamin D

Vegans also get lots of questions about calcium. Both calcium and vitamin D are needed for the development of the baby’s bones and teeth. There is some evidence that pregnant women adapt to low calcium intakes and increased needs by increasing calcium absorption and reducing calcium losses 6. This certainly is worthy of additional study and may be pertinent to vegans whose diets may be low in calcium. However, for the time being, calcium intakes of 1300 milligrams daily are recommended for women 18 and younger and of 1000 milligrams daily for women 19 through 50 7. Pregnant vegans should make a special effort to have 8 or more servings of calcium-rich foods daily. (See the Vegan Meal Plan on page 198 for more details.)

Pregnant women who have regular sunlight exposure do not need any extra vitamin D 7,8. However, if there is any question as to whether or not your sun exposure is adequate, 15 micrograms (600 IU) of dietary and/or supplemental vitamin D 7. Supplements of vitamin D should only be used with the approval of your health care provider since high doses of vitamin D can be toxic. Fortified foods like some brands of soy or other plant milks are another way to meet vitamin D needs.

Iron

Iron deficiency anemia is not uncommon during pregnancy, whether vegan or non-vegetarian. Iron needs are much higher than usual in pregnancy because of the increase in the amount of the mother’s blood and because of blood formed for the baby. Iron supplements during the second and third trimester are commonly recommended along with iron-rich foods. Additional iron may be needed in case of iron deficiency. Iron supplements should not be taken with calcium supplements and should be taken between meals in order to maximize absorption. Even when iron supplements are used, pregnant vegans should choose high iron foods like whole grains, dried beans, tofu, and green leafy vegetables daily.

Vitamin B12

The regular use of vitamin B12 supplements or fortified foods is recommended for all pregnant vegans. Vitamin B12 plays an important role in the developing fetus. Fortified foods include some breakfast cereals, some soy milks, and Red Star Vegetarian Support Formula nutritional yeast.

Folate

Folate has been in the news because of its connection with a type of birth defect called neural tube defect. Studies have shown that women who have infants with neural tube defects have lower intakes of folate and lower blood folate levels than other women. Folate is needed early in pregnancy (before many women know they are pregnant) for normal neural tube development. Many vegan foods including enriched bread, pasta, and cold cereal; dried beans; green leafy vegetables; and orange juice are good sources of folate. Vegan diets tend to be high in folate, however, to be on the safe side, women capable of becoming pregnant should take a supplement or use fortified foods that provide 400 micrograms of folate daily.

Docosahexaenoic Acid (DHA)

DHA is a type of fat that is mainly found in fatty fish. It seems to be important in the development of the brain and the retina, a part of the eye. Some DHA can be made from another fat called linolenic acid that is found in flaxseed, flaxseed oil, canola oil, walnuts, and soybeans. Choosing these foods regularly and avoiding foods containing trans fats that can interfere with DHA production, can help to enhance DHA production. Some women may opt to use a vegan DHA supplement produced from microalgae.

Iodine

Pregnant vegans who use salt should use iodized salt at the table or in cooking. The American Thyroid Association recommends that pregnant women living in the United States and Canada take a prenatal vitamin containing 150 micrograms of iodine daily 9.

All of this advice to eat a plant-based whole foods diet sounds wonderful to many pregnant women. What are the barriers to eating a healthful vegan diet?

Nausea and vomiting

Nausea and vomiting, also called morning sickness, is a concern of many pregnant women, vegans included. Many women are repulsed by foods that used to make up the bulk of their diet such as salads, dried beans, and soy milk. These aversions are extremely common in early pregnancy and are believed to be due to a heightened sense of smell, possibly due to hormonal changes 10. While every woman and every pregnancy will vary in terms of coping with nausea and vomiting, some things to try appear on page 182.

Table 15: 300 Calorie Snacks

These snacks can help to provide some of the extra calories that are needed in pregnancy. During the second trimester you need about 340 calories more per day and during the third trimester you need about 450 calories daily (compared to your pre-pregnant needs).
1 serving Fruit Whiz (p. 17)
1 serving Pita Chips (p. 36)
2 Apple Raisin Spice Muffins (p. 20)
1/2 cup Soy Milk
1 serving Hummus Spread (p. 27) on
2 slices Whole Wheat Bread
1 serving Cheesy Pita Toast (p. 37)
1 cup Apple Juice
Double serving Tofu Dip (p. 99) with
Fresh Vegetables
3 Ginger Cookies (p. 109)
1 cup Soy Milk
1 serving Karen’s Creamy Rice Pudding (p. 115)
1 large Apple
1 cup Soy Yogurt with
2 Tbsp Nuts and Dried Fruit
1 Bagel with
1 Tbsp Almond Butter
1 serving Thick Shake (p. 18)
1 serving Easy Pasta Salad (p. 44)
1 Banana
Double serving Split Pea Dip (p. 36) with
Double serving Pita Chips (p. 36)
1 Mini Pizza (p. 34)

Coping with nausea and vomiting:

  • If it tastes good, eat it! I can remember wanting nothing but saltines and ginger ale for days at a time. Then, one day when my husband was warming up some left-over pasta, it smelled wonderful. I ate 3 bowls full and never regretted it.

  • Try eating low fat, high carbohydrate foods. These are digested more quickly and stay in the stomach for less time giving less time for queasiness.

  • Eat often. Sometimes nausea is really due to hunger.

  • Avoid foods that have strong smells. Sometimes cold foods are better tolerated because they don’t smell as much. Have someone else do the cooking if possible and go away from the house while cooking is being done.

  • Be sure to drink juice, water, soy milk, or miso broth if you can’t eat solid food. Keep trying to eat whatever you can.

  • Contact your health care provider if you are unable to eat or drink adequate amounts of fluids for 24 hours.

Lack of Time

Whether you’re working full time outside the home or at home full time (or some variation), the thought of preparing elaborate meals and snacks will probably seem daunting. Meals do not have to be elaborate. A meal can be as simple as a bowl of cereal and fruit with soy milk, peanut butter and crackers, or a baked potato and a salad. Use convenience foods like canned beans, frozen vegetables, mixes, pre-chopped vegetables, and frozen entrées to reduce preparation time. Use time-saving appliances like crockpots, pressure cookers, and microwave ovens. Plan to have leftovers. Check out some quick and easy vegan cookbooks for ideas.

Your Health Care Provider

While many family practice physicians, obstetricians, and nurse-midwives may be quite knowledgeable about nutrition, many are not familiar with vegetarian and especially vegan diets. Your health care provider may have lots of questions about what you are eating and whether or not you will be able to meet your needs. Look on this as an opportunity to educate someone about vegan nutrition. Try sharing this chapter and other materials from the resource list with your health care provider. Keeping a record of what you eat for several days may help convince your health care provider that what you’re doing is fine or may highlight areas needing improvement. If you have specific concerns and questions, you may choose to consult a registered dietitian (RD) with expertise in vegetarian nutrition. Remember, a varied vegan diet can meet your needs and the needs of your baby during this exciting time.

It is also important to think about alcohol and smoking. Moderate to large amounts of alcohol during pregnancy can cause fetal alcohol syndrome, which impairs mental and physical development. Even one or two drinks of alcohol daily are associated with greater risk of health and development problems for the baby. Based on what we know, women should avoid alcohol during pregnancy. Cigarette smoking has been clearly linked to low birth weight, which increases the infant’s chance of having a variety of health problems. Smoking should also be avoided during pregnancy.

The Vegan Food Guide on page 198 can be used in pregnancy. Note the modifications to meet increased needs for protein and other nutrients.

Sample Menu Plan for Pregnant Vegans:

BREAKFAST SNACK
1/2 cup oatmeal with maple syrup
1 slice whole wheat toast with fruit spread with margarine
1 cup EdenSoy Extra soy milk
1/2 cup calcium and vitamin D fortified orange juice
1/2 whole wheat bagel
Banana
LUNCH SNACK
Veggie burger on whole wheat bun with 3/4 cup ready-to-eat mustard and catsup
1 cup steamed collard greens
Medium apple
1 cup EdenSoy Extra soy milk
cereal with 1/2 cup blueberries
1 cup EdenSoy Extra soy milk
DINNER SNACK
3/4 cup tofu stir-fried with 1 cup vegetables
1 cup brown rice
Medium orange
Whole grain crackers with 2 Tbsp peanut butter
4 ounces apple juice
Nutritional analysis of sample menu
RDA/AI
2240 calories  
100 grams protein (18% of calories) 71 grams
55 grams fat (22% of calories)  
336 grams carbohydrate (60% of calories)  
1688 mg calcium 1000 mg
32.5 mg iron 27 mg
11.2 mg zinc 11 mg
2.1 mg thiamin 1.4 mg
1.4 mg riboflavin 1.4 mg
23.1 mg niacin 18 mg
9 mcg vitamin B12 2.6 mcg
4.2 mcg vitamin D 15 mcg (supplement/sun exposure indicated)
850 mcg folate 600 mcg

References

  1. Carter JP, Furman T, Hutcheson HR. Preeclampsia and reproductive performance in a community of vegans. Southern Med J 1987;80:692-697.
  2. 2 O’Connell JM, Dibley MJ, Sierra J, et al. Growth of vegetarian children: The Farm study. Pediatrics 1989;84:475-481.
  3. Rasumssen KM, Yaktine AL. Weight Gain During Pregnancy: Reexamining the Guidelines. Washington, DC: Institute of Medicine, National Research Council, 2009.
  4. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: National Academy Press, 2002.
  5. Carlson E, et al. A comparative evaluation of vegan, vegetarian, and omnivore diets. J Plant Foods 1985; 6:89-100.
  6. Prentice A. Maternal calcium metabolism and bone mineral status. Am J Clin Nutr 2000;71(suppl):1312S-16S.
  7. IOM (Institute of Medicine). Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: The National Academies Press; 2011.
  8. Specker BL. Do North American women need supplemental vitamin D during pregnancy or lactation? Am J Clin Nutr 1994;59(suppl):484S-91S.
  9. Becker DV, Braverman LE, Delange F, et al. Iodine supplements for pregnancy and lactation — United States and Canada: recommendations of the American Thyroid Association. Thyroid 2006;16:949-51.
  10. Erick M. Hyperolfaction as a factor in hyperemesis gravidarum. Considerations for nutritional management. Perspectives in Applied Nutrition 1994;2:3-9.

Thanks to VRG volunteer Alan Polster for converting this document into HTML.