Is a vegan diet safe during pregnancy?

Yes.

It is always important to maintain a healthy diet, but it is especially important during your pregnancy. What you choose to eat while expecting may influence both you and your  baby’s current and future health. That being said, as long as you are eating a healthy, well-balanced diet with plenty of protein, a vegan diet is a safe choice.

What is a vegan diet?

A vegan diet is defined as not consuming any animal products which includes red and white meats, chicken, fish, cheese, milk, and eggs. The truest vegan diet is solely plant based. The vegan diet, when carefully planned, can meet all of the nutritional needs for you and your developing baby. If you have been following a vegan diet for a long time, it is important you check in with your doctor and a registered dietitian to ensure you are nutritionally prepared to carry a child before adding the metabolic demands of pregnancy.

The essential components of a nutritious diet are defined by the Recommended Dietary Allowances (RDAs) and set by nutrition researchers. According to them, a nutritious diet contains a collection of nutrients—carbohydrates, fats and proteins—that provide calories or energy in addition to vitamins and minerals. We as nutritionists encourage people to get the majority of their nutrients from food rather than supplements. Prenatal vitamins can provide nutrients, but do not provide protein and energy, and every prenatal vitamin is different so it is important to read the labels carefully.

Watch out for these nutrients

If you are following a vegan diet, these nutrients may need special attention:

Protein. Protein helps build fetal muscles, nerve connections, enzyme systems in the fetus, and new tissues in the mother’s uterus, blood, and breasts. Foods that are vegan-friendly and are a good source of protein include dried beans and peas, soybeans, tofu, seitan, nuts, nut butters, whole grains, soy cheese, and soy yogurt.

Iron. Although iron does not provide energy to the body, it is important for myelin development, the tissues which surround nerves in the central nervous system and act as a type of insulation. It is also vital in red blood cells to carry oxygen to the developing fetal brain. The best vegan foods that are rich in iron are whole grains, leafy green vegetables, dried fruit, prune juice, soybeans, dried legumes, black strap molasses, tofu, and fortified cereals and soy milk. It is recommended to have a high vitamin C food, or beverage, in the same meal, such as orange juice to aid in iron absorption.

Zinc. Important for building muscles for the developing fetus and to help the mother maintain a healthy immune system, the best vegan-friendly foods in this category are whole grain cereals, peas, dried beans, nuts, seeds, and tofu.

Calcium. Calcium helps build strong bones and teeth for a baby, as well as for mom. Calcium-rich non-dairy foods include bok choy, collards, Chinese cabbage, kale, broccoli, turnip greens, okra, almonds, almond butter, tahini, figs, baked beans, soybeans, calcium-set tofu, and fortified juices, breakfast cereals and soy milk.

Choline. The recommended dietary intake is 400 mg day for  girls 14-18 years old and increases to 425 mg for older women. Choline is widely distributed in food as lecithin. Examples include eggs, liver, soybeans, beef, milk, and peanuts. Choline in vegan foods include soybeans, soy flour, tofu, sun dried tomatoes and peanuts. Given the limited food selection, you can speak with your doctor about considering a supplement.

Vitamin D. Vitamin D, in partnership with calcium, is key in creating healthy bones and teeth for the developing fetus. It also is important in maintaining a healthy maternal skeleton. Additionally, vitamin D plays a role in the maternal immune function support and may help reduce the risk of pre-eclampsia. The best plant food source of vitamin D is fortified milk. Other sources include fortified foods, such as some cereals, some brands of soymilk, and rice.

Vitmain B12. This vitamin is extremely critical for nerve development in the fetus as well as red blood cell maintenance. Women who do not ingest enough may need intramuscular monthly injections. To assure adequate B12 intake, try to eat at least one of the following foods each day: fortified cereals, fortified soy milk, Red Star brand nutritional yeast, and fortified meat substitutes.

Folic Acid. This helps to prevent neural tube defects or spina bifida. You should begin incorporating this into your diet before trying to conceive. Foods with folic acid include dark green leafy vegetables, orange juice, wheat germ, bran flakes, whole grains, and legumes.

Iodine. Iodine is important for energy metabolism and critical for intellectual development in the fetus. Vegetables reflect the iodine content of the soil they are grown in, and vegetables grown closer to the ocean are likely to have higher iodine contents. Iodized salt was developed to prevent widespread iodine deficiencies. Potatoes with the peel or navy beans are also good vegetarian sources. Sea vegetables like nori and hiziki can provide iodine, but in variable quantities. Maternal iodine intakes above 1100 mcg/d should be avoided.

Omega 3 fatty acids. Omega-3 fatty acids include eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and alpha-linoleic acid (ALA). EPA and DHA are important in the development of an infant’s brain and eyes and may help prevent pre-term labor, pre-eclampsia and protect against postpartum depression. ALA sources include ground flaxseed, flaxseed oil, canola oil, soybean oil, soybean products, and walnuts. Vegetarian DHA and EPA supplements derived from microalgae are available.

Miriam Erick is an inpatient senior registered dietitian and manager in the Department of Nutrition at Brigham and Women’s Hospital.  She is also the author of “Managing Morning Sickness: a survival guide for pregnant women” and the e-book, “Take Two Crackers and Call Me in the Morning! A real-life guide for surviving morning sickness”.

Sarah Elizabeth Little, MD, MPH, is a Maternal-Fetal Medicine specialist in the Department of Obstetrics and Gynecology at Brigham and Women’s Hospital.