Many women are misled to believe that they can’t have a healthy pregnancy following a plant-based diet. According to the American Academy of Nutrition and Dietetics/Dietitians of Canada, “appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood, and for athletes” (1).
So the question then becomes, what does an appropriate planned vegan diet look like?
The nutrition guidelines for pregnancy outlined below will provide you with all the answers you need to build a healthy baby and have a nourishing pregnancy.
Weight Gain Targets
In the past, women were encouraged to “eat for two” and not worry about over-indulging on calorie-dense foods. And while pregnancy is certainly not a time to follow a restrictive diet, we now know that gaining too much weight in pregnancy can increase a women’s risk for pregnancy-related complications. The chart below highlights weight gain guidelines, according to Health Canada and the Institute of Medicine (2):
If your rate of weight gain is quicker or slower than the rate recommended above, it’s important to make an appointment with your physician and dietitian.
Energy Needs in Pregnancy
If you don’t need to eat for two, then how much do you need to eat during pregnancy?
The answer to this question depends on what your pre-pregnancy weight is and what trimester you are in. Women with a BMI between 18.5-24.9 should consume an extra 350 calories in the 2nd trimester (think large snack) and 450 calories in the 3rd trimester (think mini meal). If your BMI is lower than this range, you will need more food. If your BMI is higher than this range, you will need less food.
Protein-rich foods provide essential nutrients and are needed by baby to grow muscle and other tissues. As such, it’s important to plan your meals and snacks around plant-based sources of protein, such as seitan, tofu, tempeh, beans, lentils, nuts, and seeds. Doing so will not only ensure that you meet your protein requirements (which are ~10% higher than omnivore diets), but will help you to get sufficient amounts of iron, zinc, folic acid, and magnesium. In general, pregnant women at a BMI between 18.5 and 24.9 should aim for a protein intake of ~ 1.2 g per kg body weight or 0.5 g per lb of body weight.
During pregnancy, iron requirements are significantly higher because of an increase in mom’s blood volume. In addition, baby’s iron stores are being built up through mom’s diet for his or her first ~6 months of life. Vegans may need 80% more iron compared to non-vegans. Therefore, it’s important to include iron in both supplemental and dietary forms. Quality sources of plant-based iron are found in protein-rich foods listed above. You can also enhance your body’s ability to absorb iron by including a source of vitamin C with meals and separating foods high in iron from those containing caffeine and calcium.
Calcium is an essential nutrient used to build your baby’s bones and teeth. Requirements for calcium are not different in pregnancy since your body absorbs calcium better when you are pregnant. To ensure you are meeting your calcium needs of 1000 mg per day, include at least 1-2 cups plant milk per day, outside of meals (since calcium can interfere with absorption of iron), along with calcium-rich plant foods like kale, broccoli, bok choy, tahini, almonds, tofu and tempeh.
This essential nutrient is produced in our skin following exposure to UV light. However, in countries/states that fall above 37 degrees north, such as Canada, making vitamin D year-round is not possible. In addition, cloud coverage, skin pigmentation, smog, and sunscreen can reduce the amount of vitamin D our bodies produce. As such, it is wise to ensure that your prenatal supplement includes at least 600-1000 IU of vitamin D.
Folate is a B vitamin that is needed to develop a baby’s spine, brain, and skull, especially during the first four weeks of pregnancy. A folate deficiency in pregnancy can increase the risk of developing neural tube defects, which is a deformation of the brain or spinal cord. Since folate is so important in early pregnancy, it is recommended that all women consume a folate-rich diet and take a folic acid supplement providing 400 mcg folic acid 2-3 months before conception (3). Typical vegan diets provide folate well above this minimum requirement.
Iodine is an essential mineral that helps to regulate function of the thyroid hormone. In pregnancy, it is needed to support healthy brain development in the fetus. Needs during pregnancy are 220 mcg and should not exceed 1100 mcg. Few foods provide a good source of iodine, which is why iodine (in Canada) is added to table salt (1/2 tsp = 190 mcg iodine). To ensure you are meeting your iodine needs, only use salt that has iodine added and ensure that your supplement contains at least 150 mcg of iodine per tablet.
All vegans should supplement with vitamin B12 since there are no good, reliable sources of the nutrient. In pregnancy, supplementation is even more important since deficiency in the developing fetus can result in cognitive changes that can be permanent. B12 requirements in pregnancy are 2.6 mcg and can easily be met by most prenatal supplements.
Zinc is an important nutrient with many roles in the body that promote normal growth and development in children. Like iron, needs may be slightly higher (by ~50%) in vegans and are further increased by the demands of pregnancy. Zinc can be found in protein-rich plants, and is especially concentrated in wheat germ.
DHA and EPA are long-chain omega 3 fats critical for a baby’s neurodevelopment during pregnancy. Although there is currently no consensus on how much omega 3 from EPA/DHA women should consume during pregnancy, the American Academy of Nutrition and Dietetics and Dietitians of Canada advise healthy adults to consume 500 mg of EPA/DHA per day (4), which can be met by supplementing with algae-derived DHA.
Are there any foods to avoid in pregnancy?
The following foods and ingredients should be limited or completely avoided in pregnancy due to a potential risk of harm to the fetus.
Total caffeine intake should not exceed 300 mg per day, the equivalent of 1-2 250 mL cups of brewed coffee per day. Levels above this can increase the risk of miscarriage and low birth weight (5).
Most artificial sweeteners have been found to be safe in pregnancy when consumed in small, infrequent amounts. Artificial sweeteners containing cyclemates (Sugar Twin®, Sweet N’ Low®) should be avoided.
No amount of alcohol has been shown to be safe in pregnancy. Consuming alcohol when pregnant can lead to a low birth weight, developmental and neurological birth defects, and having a baby with fetal alcohol spectrum disorder (FASD).
Despite their natural origins, many herbal teas can put your baby at risk. Below is summary of teas that should be avoided during pregnancy (6):
Using Cronometer in Pregnancy
Cronometer is a useful tool to help pregnant (and breastfeeding) women ensure they are meeting their nutrient needs. The first step to using Cronometer when pregnant is to set your account to “pregnant” or “breastfeeding”, as shown below:
Selecting this option will automatically adjust your targets for calories, protein, vitamins, and minerals to be consistent with the recommendations outlined in the Institute of Medicine’s Dietary Reference Intakes.
Another useful feature of Cronometer that can help you have a healthy pregnancy is the “Oracle”. If you notice that you are low in a nutrient, the Oracle can suggest foods to help you meet your nutrient needs.
As you can see from the example below, my diet was lacking in vitamin B5. The Oracle suggested that I add mushrooms to my diet in order to meet 100% of the DRI for this vitamin. (Note that vitamin D is still low in my diet since this nutrient is not commonly found in foods.) You can also set the oracle feature to only provide suggestions for foods that are derived from plants.
Pregnancy is truly a special time in the lives of parents-to-be, but it can also be overwhelming and nerve-wracking. If you have any questions about your nutritonal health during pregnancy, please be sure to consult your family doctor and book an appointment with a Registered Dietitian skilled in vegan nutrition
- Melina V, Craig W, Levin S. Position of the Academy of Nutrition and Dietetics: vegetarian diets. J Acad Nutr Diet. 2016 Dec;116(12):1970-1980. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/27886704
- Food and Nutrition Board, Institute of Medicine; Board on Children, Youth and Families. Weight gain during pregnancy: reexamining the guidelines [Online]. 2009. Available from: http://books.nap.edu/catalog.php?record_id=12584#orgs
- Practice-based Evidence in Nutrition. Pregnancy: Practice guidance toolkit [knowledge pathway online]. 2017 May. Available from: http://www.pennutrition.com. Access only by subscription
- Kris-Etherton PM, Innis S, for the American Dietetic Association, Dietitians of Canada. Position of the American Dietetic Association and Dietitians of Canada: dietary fatty acids. J Am Diet Assoc. 2007;107:1599–1611. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/17936958
- Dietitians of Canada. What is the impact of caffeine intake in pregnancy and lactation? In: Practice-based Evidence in Nutrition [knowledge pathway online]. 2009 Apr. Available from: http://www.pennutrition.com. Access only by subscription
- Alberta Health Services. Nutrition Guideline: Pregnancy [Online]. 2013 Mar. Available from: https://www.albertahealthservices.ca/assets/Infofor/hp/if-hp-ed-cdm-ns-4-1-1-pregnancy.pdf