How can you meet these increased needs by following a vegan diet? A series of studies [2,3] at the Farm, a community where vegan diets are part of a socially responsible lifestyle, have shown that vegans can have healthy pregnancies and that infants and children can safely follow a vegan diet. This article will review nutritional needs during pregnancy and will describe how a vegan diet can be adapted to meet the higher nutritional needs associated with pregnancy.
Although recommendations for many vitamins and minerals are higher in pregnancy, the increase in energy (calorie) requirements is relatively small. For this reason, some care and thought are needed by all pregnant women to insure that nutritional needs are met.
Step 1. Take your prepregnant weight (in pounds) and divide it by your height (in inches) squared; then multiply by 700. BMI = lb/in squared 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.
BMI Weight for Recommended
Height Status Weight Gain
_____________________________________________________
under 19.8 Low 28-40 pounds
19.8 to 26 Average 25-35 pounds
26 to 29 High 15-25 pounds
over 29 Very High no less than 15 lbs
In order to support the recommended weight gain, you will need about 300 calories more than usual in the second and third trimesters [1]. There is little, if any, increase in calorie needs in the first three months of pregnancy. Three hundred calories is a fairly small increase compared to the increases seen for other nutrients, so it is important to use those calories wisely. In other words, instead of drinking two cans of soda (300 calories, but not good nutritionally) you could eat 300 calories worth of fruits and vegetables and meet your needs for many vitamins and minerals.
Your best guide for how much you should be eating is your own body. If you select healthy foods, exercise moderately, and eat regularly, your feelings of hunger should let you know when and how much to eat.
The newest recommendations for protein needs in pregnancy are lower than previous recommendations. The current RDA for protein in pregnancy is 60 grams per day [1]. This is 10 grams above the recommendation for non-pregnant women age 25-50 and 14 grams above the recommendation for non-pregnant women age 19-24 years. If your diet is varied and contains good protein sources such as soy products, beans and grains, you can relax and not worry about getting enough protein in pregnancy. Some ways that you can get another 10-15 grams of protein within the extra 300 calories are: 2 cups of plain soy milk, 9 ounces of tofu, 3 ounces of tempeh, 1 cup of cooked beans, 1-1/2 bagels. This is in addition to the protein which normally occurs in your diet. Making sure you have enough calories insures that the protein you eat is used for tissue synthesis rather than meeting energy needs.
Other important nutrients in pregnancy include calcium, vitamin D, iron, vitamin B12, zinc and folic acid.
Calcium and vitamin D both are needed for bone and tooth development. Calcium absorption is high in pregnancy [5], so if your diet is slightly low in calcium, your body may automatically compensate for it. There is little evidence of calcium loss from the mother's bones during pregnancy and no adverse effects of diets low in calcium during pregnancy have been reported [4]. However, since low calcium intakes are not recommended during the years when women are accumulating bone mass, an intake of 1200 mg per day is recommended for women under age 25 [1,4]. Intakes of between 600 and 1200 mg per day of calcium are recommended for pregnant women age 25 and older [1,4]. Vegans may need less calcium than omnivores because the vegan diet may result in lower losses of calcium due to the lower protein nature of the diet.
During pregnancy, eating four or more servings of calcium-rich foods daily is recommended. Ideas for these foods include greens, tofu processed with calcium sulfate, and blackstrap molasses. Try snacking on tahini on toast or eat some figs. Take a box of frozen greens (spinach, collards, kale, etc) to work and heat it in the microwave for a calcium-rich afternoon snack. Calcium supplements represent another option for those days when your appetite is poor or you don't have time to prepare foods. You should be aware, however, that calcium supplements can cause constipation.
Vitamin D, which is produced following exposure of skin to sunlight, is not normally found in foods eaten by vegans. Pregnant vegans should be sure to get at least 20 to 30 minutes of summer sun on their hands and face two to three times a week [6]. Vitamin D supplementation should be undertaken only with the approval of your physician, since excess vitamin D is toxic and can produce fetal deformities. A vitamin D supplement of 10 micrograms (400 IU) daily should be taken by pregnant vegans who live at northern latitudes in the winter (due to reduced intensity of sunlight) and by those with minimal exposure to sunlight (for example, those who work indoors during daylight hours) [4].
Extra iron is needed in pregnancy to provide for increased maternal blood volume and for the formation of the baby's blood. If the mother does not have enough iron in her diet, she will draw on her iron stores and can become anemic. The RDA for iron in pregnancy is 30 mg per day [1] which is difficult (though not impossible) to get on any diet. If you feel that you are not able to get this much iron from diet alone, you should consider using a low-dose iron supplement. Also, if you have a history of anemia your iron stores may already be low, so you will need more than 30 mg of iron daily. The iron supplement that you take should only be taken in combination with a good diet. High doses of iron will actually interfere with zinc and copper absorption [7-9] and so should be avoided if possible.
Vitamin B12 needs are higher in pregnancy due to vitamin B12's role in tissue synthesis. If you are planning to breast feed, you will also need to make sure that you have enough vitamin B12 stored so that your milk vitamin B12 will be high enough to meet the infant's needs. One brand of yeast, Red Star T6635+ has been tested and shown to contain active vitamin B12. This brand of yeast is a reliable source of vitamin B12. The RDA for pregnancy for vitamin B12 is 2.2 micrograms daily. A rounded teaspoon of yeast powder or 2 teaspoons of mini-flake yeast or 2-1/2 tablespoons of large-flake yeast provides 2.2 micrograms of vitamin B12. Of course, since vitamin B12 is stored, you could consume larger amounts of nutritional yeast less often. Another alternative source of vitamin B12 is fortified cereal. Nutri-Grain cereal contains vitamin B12 at this time. 2.2 micrograms of vitamin B12 are provided by 1.5 ounces (about one cup) of wheat Nutri-Grain. Check the label of your favorite cereal because manufacturers have been known to stop adding vitamin B12. Other sources of vitamin B12 are fortified soy milk (check the label as this is rarely available in the US), vitamin 12 fortified meat analogues (food made from wheat gluten or soybeans to resemble meat, poultry or fish), and vitamin B12 supplements. There are vitamin supplements that do not contain animal products.
Zinc is a mineral which is necessary for growth and development. Good sources of zinc include grains and nuts. Folic acid is another nutrient whose requirement appears to be substantially increased in pregnancy. Dark leafy greens are the richest source of folic acid for vegans. Other good sources include whole grains, nuts, legumes and oranges.
Caffeine is more controversial. Large amounts have, in some cases, been associated with various problems in pregnancy [10]. Caffeine does not appear in the fetus' blood in the same concentration as in the mother's blood. It is probably wisest to limit or avoid caffeine-containing beverages such as coffee, tea and cola.
PLAN I
Nuts, Seeds or Legumes 2 servings (a serving is 2 TB nuts
or seeds or 1/2 cup cooked legumes)
Milk or Meat Analogues 3 servings (a serving of soymilk
is one cup)
Vegetables 4 servings (a serving is 1 cup
raw or 1/2 cup cooked). We suggest
emphasizing high calcium vegetables
such as greens and broccoli.
Fruits 5 servings (a serving is 1 fruit or
1/2 cup canned fruit)
Grains, Cereals or 6 servings (a serving is 1 slice of
Breads bread or 1/2 cup cereal or grain)
PLAN II
Legumes 4 servings
Milk or Meat Analogues 4 servings
Vegetables and Fruits 8 servings We suggest emphasizing high
calcium vegetables such as greens and
broccoli.
Grains, Cereals or 6 servings
Breads
2. O'Connell JM, Dibley MJ, Sierra J, et al: Growth of vegetarian children: The Farm Study. Pediatrics 84: 475-481, 1989.
3. Carter JP, Furman T, Hutcheson HR: Preeclampsia and reproductive performance in a community of vegans. Southern Med J 80: 692-697, 1987.
4. Institute of Medicine Subcommittee on Nutritional Status and Weight Gain During Pregnancy: Nutrition During Pregnancy. Washington,DC: National Academy Press, 1990.
5. Heaney RP and Skillman TG: Calcium metabolism in human pregnancy. J Clinical Endocrinol Metab 33: 661-670, 1971.
6. Specker BL, Valanis B, Hertzberg V, et al: Sunshine exposure and serum 25-hydroxyvitamin D concentrations in exclusively breastfed infants. J Pediatr 107: 372-376, 1985.
7. Solomons NW: Competitive interaction of iron and zinc in the diet: Consequences for human nutrition. J Nutr 116: 927-935, 1986.
8. Hambidge KM, Krebs NF, Sibley L, et al: Acute effects of iron therapy on zinc status during pregnancy. Obstet Gynecol 4: 593-596, 1987.
9. Dawson EB, Albers J, McGanity WJ: Serum zinc changes due to iron supplementation in teenage pregnancy. Am J Clin Nutr 50: 848-852, 1989.
10. US Department of Health and Human Services: The Surgeon General's Report on Nutrition and Health. Washington, DC: US Government Printing Office, 1988.
11. Johnston PK: Counseling the pregnant vegetarian. Am J Clin Nutr 48: 901-905, 1988
If you eat too little while breastfeeding, you may not produce as much milk. Although the recommended caloric intake is 500 calories above your usual intake [1], you may still lose weight because of a loss of calories in breast milk. It is safe to lose about 1/2 to 1 pound a week while breastfeeding but more rigorous dieting is not recommended. As in pregnancy, small frequent meals are the best way to be sure that you are getting enough calories. Since you do need extra fluid while breastfeeding, use nutritious beverages like juices, soy milk, soups and smoothies to provide calories.
The recommendation for protein is only 5 grams higher than it is in pregnancy [1] and can be obtained easily from the extra food you are eating. you should still eat good quality food because you are providing all nutrients to your infant. you will need to be careful to get enough vitamin B12 and vitamin D in order to be sure that these nutrients are present in your milk in adequate amounts. See the Pregnancy section for more information on sources of vitamin B12 and vitamin D. Requirements for most other nutrients are similar to those in pregnancy and should be obtained from a varied, healthy vegan diet.