As a newly pregnant mother, you may be wondering what the best diet to follow during your pregnancy is, to ensure the optimal health of you and your child. In this article we explain (in plain English!) the conclusions of scientific studies that have looked at vegetarian pregnancy.
A healthy, nutritious diet is essential during pregnancy and plays a role in the health of your offspring. Adequate dietary consumption of macro nutrients such as protein, carbohydrates, and fat as well as vitamins and minerals such as iron, vitamin B12, calcium and folic acid (vitamin B9) are all required for proper development of your growing unborn child (Melina et al., 2016).
Vegetarian diets consist of plant-based foods rich in whole grains, legumes, nuts, seeds, fruits, and vegetables, while avoiding red meat, processed meat products, refined foods, and sweets.
There are several variations of a vegetarian diet:
Complications that may arise during pregnancy and birth are, to name a few: gestational diabetes mellitus (GDM), preterm birth, preeclampsia, spina bifida, high blood pressure, low birth weight, and anaemia. In the sections that follow we highlight studies that explain how a vegetarian diet during pregnancy can reduce (or eliminate) the risk of those complications. But first, we briefly cover how a vegetarian diet can be detrimental to women during pregnancy.
Drawbacks of a Vegetarian Pregnancy
Some may argue that a vegetarian diet during pregnancy could be detrimental to the health of both mother and child, particularly due to a lack of folic acid and vitamin B12.
According to a study published in the International Journal of Obstetrics and Gynaecology “folic acid and vitamin B12 levels are lower in women with neural tube defect pregnancies” (Wald et al., 1996). Vitamin B12 is an essential nutrient that our bodies need to produce red blood cells and DNA. Food sources of vitamin B12 include beef, salmon, tuna, and dairy products – all foods that are lacking in a vegetarian diet. Individuals who westernized diet were more at risk of their offspring developing spina bifida “low maternal intake of vegetables, fruit, fish and whole grains was associated with a two-fold increased spina bifida risk” (Vujkovic et al., 2009). Dietary sources of folic acid (vitamin B9) include legumes, dark leafy greens, and broccoli. According to Vujkovic et al. (2009) “A healthy diet contains enough folate to reach similar protective effect as supplementation”.
Benefits of a Vegetarian Pregnancy
Despite the drawbacks of a plant-based diet during pregnancy covered in the previous section, numerous studies have reported the many health benefits of a vegetarian pregnancy.
According to the Academy of Nutrition and Dietetics “An appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits for 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” (Melina et al., 2016).
In the sections that follow we highlight studies that have linked vegetarian pregnancy with reduction in gestational diabetes, preeclampsia, preterm birth, paediatric diseases, depression, and anxiety.
Prevention of Gestational Diabetes
Plant-based diets may prevent the incidence of Gestational Diabetes Mellitus (GDM) during pregnancy.
GDM is a condition developed during pregnancy in which your body becomes glucose intolerant. It can lead to complications such as preterm birth, and increased risk of a caesarean. It is possible to recover from GDM after pregnancy, however some women may develop a long-term condition such as type 2 diabetes (T2D) “Woman who develop GDM usually recover after pregnancy but up to 55% will develop T2D” (Schiattarella et al., 2021).
Plant-based diets seem to have a protective affect against GDM. This could be due to the higher fiber content in vegetarian diets. Fiber slows the rate at which carbohydrates are broken down into simple sugars like glucose which can enter the bloodstream and cause a spike in your blood sugar levels. Fiber also increases your bodies sensitivity to insulin (a hormone) which in turn reduces the amount of sugar in your blood. Healthy unsaturated fats, such as n-3 PUFAs (Polyunsaturated fatty acids) commonly known as omega-3 fatty acids may also play a role in increasing our bodies sensitivity to insulin and thus lowering blood sugar levels. Plant-based sources of these healthy fats are found in nuts (especially walnuts), olive oil, and flaxseeds.
Plant-based diets seem to have a positive impact on the human gut microbiota (the trillions of microbes which have made themselves at home in our intestines). Plant-based nutrition leads to a higher abundance of good gut bacteria “a vegetarian diet in early pregnancy is associated with a different composition of the gut microbiota compared to an omnivorous diet” (Barrett et al., 2018).
Recently we are learning more about the positive relationship between our gut microbes and reduced risks of cardiovascular disease, cancer, type-2 diabetes and inflammatory bowel disease. Dietary fiber increases the amount of “good bacteria” in our gut which increases the amount of beneficial metabolites such as short-chain fatty acids (SCFAs) which have shown to have a protective effect on our immune system and inflammation in the body. A study conducted by The Harvard School of Public Health reported that a “diet with low fiber and high glycemic load was associated with an increased GDM risk” (Zhang et al., 2006). Further evidence backs up the claim that plant-based diets are beneficial against developing GDM “Adherence to a Mediterranean diet pattern of eating is associated with lower incidence of GDM and better degree of glucose tolerance” (Karamanos, 2013 & Zamani, 2019).
Prevention of Preeclampsia (High Blood Pressure)
Preeclampsia is a dangerous complication that can develop during pregnancy and is associated with hypertension and raised blood pressure. Late detection can lead to grave consequences for you and your baby.
Diet could play a beneficial role in preventing preeclampsia “Intake of fruits and vegetables, low-fat dairy products, total cereal and dark bread were each associated with a reduced risk of preeclampsia” (Frederick et al., 2005). Another study reported that women who consumed more than 3 portions of vegetables a day were at less risk of developing hypertension during pregnancy (Longo-Mbenza, 2005). According to Carter et al. (1987) “It is possible that a vegan diet could alleviate most, if not all, of the signs and symptoms of preeclampsia”.
Prevention of Preterm Birth
Plant-based diets may reduce the risk of preterm birth.
The CDC (Centers for Disease Control and Prevention) reported that preterm births affect 1 out of every 10 infants born in the United States. According to a study published in The American Journal of Clinical Nutrition “A vegetable, fruit, and white rice dietary pattern during pregnancy is associated with a lower risk of preterm birth and larger birth size” (Chia et al., 2016). Researchers from the Danish Epidemiology Science Centre found that “shifting towards a Mediterranean diet during pregnancy may reduce the risk of early delivery” (Mikkelsen et al., 2009).
Plant-based diets also appear to be beneficial for birthweight outcomes “Consumption of whole foods such as fruit, vegetables, low-fat dairy, and lean meats throughout pregnancy appears beneficial for appropriate birthweight” (Grieger & Clifton, 2015).
Prevention of Paediatric Diseases
Plant-based diets during pregnancy may decrease the risk of your child developing paediatric diseases, such as diabetes, asthma, paediatric wheeze, eczema and cancer.
According to a study conducted by the University of Edinburgh “Adherence to a Mediterranean diet was protective for persistent wheeze and atopy” (Nurmatov et al., 2011). Another study reported that “Higher maternal intake of green and yellow vegetables, citrus fruit, and β-carotene during pregnancy was significantly associated with a reduced risk of eczema in offspring” (Miyake et al., 2010). A study published in the Journal of Cancer Epidemiology reported that “Maternal adherence to Mediterranean diet components seemed to be inversely linked to childhood acute lymphoblastic leukemia (ALL)” (Dessypris et al., 2017).
Prevention of Depression and Anxiety (in Both Mother and Child)
A plant-based diet during pregnancy is associated with a reduced risk of depression and anxiety in mothers (Baskin et al., 2015). A vegetarian diet could also play a role in the mental health of your child, and lower the risk of childhood depression “maternal adherence to a Mediterranean diet in early pregnancy was associated with favourable neurobehavioral outcomes in early childhood” (House et al., 2018).
Maternal vegetarian diets during pregnancy did not impact the cognitive ability of the child “a vegetarian diet during pregnancy had no discernible negative effects on the cognitive function of the children at 6 to 7 years of age” (Crozier et al., 2019).
Poor nutrition during pregnancy and the postnatal period was associated with childhood behavioural and emotional problems “Higher intakes of unhealthy foods during pregnancy predicted externalizing problems among children” (Jacka et al., 2013).
Increase in Childhood Consumption of Vegetables
Maternal adherence to a vegetarian diet may lead to a higher consumption of vegetables in children “Higher maternal vegetable consumption and longer breast-feeding duration were synergistically associated with high child vegetable consumption at 6 years” (Beckerman et al., 2020).
The Importance of a Proper Vegetarian Diet During Pregnancy
When following a plant-based diet it is important to ensure that you are eating the right amount of calories through-out each trimester. Consulting with your physician and monitoring for possible deficiencies such as vitamin B12, iron, folic acid, and vitamin D, and supplementing where necessary (Piccoli et al., 2017). Ensure that you are consuming adequate amounts of wholegrains, nuts, seeds, legumes, fruit, vegetables, and olive oil.
Well-planned vegetarian diets offer many health benefits for mothers during their pregnancy, and protect them from potentially serious complications “balanced plant-based diets rich in fibers and low in fat are considered to be protective against poor pregnancy outcomes. Unbalanced dietary patterns with lack of macro- and micronutrients such as proteins, vitamin B12, vitamin D, calcium, DHA, and iron are at more risk of fetal impairment (low BW, neurological disabilities, and fetal malformations)” (Sebastiani et al., 2019).
A well-planned and varied plant-based diet can meet and/-or exceed your dietary requirements for all essential nutrients during your pregnancy, keeping you and your baby healthy through-out this incredibly joyous moment in your life. Plant-based diets can also set your child up for optimal health conditions during their first few years of life - with improved mental cognition, and reduced risks of obesity and diabetes.
Vegetarian while Pregnant Studies
Benefits of Vegetarianism while pregnant
Name of Paper
Link to Paper
The Impact of a Plant-Based Diet on Gestational Diabetes: A Review
A Qualitative Exploration of Pregnancy Experience With a Nutrient-Dense, Plant-Rich Dietary Pattern: A Pilot Study
American Journal of Lifestyle Medicine
The Effect of a Maternal Plant-Based Diet During Pregnancy on Obesity and Diabetes in the Offspring
Doctoral dissertation, Boston University
Maternal diet during lactation and breast-feeding practices have synergistic association with child diet at 6 years
Public Health Nutrition
Association of a plant-based dietary pattern in relation to gestational diabetes mellitus
Nutrition and Dietetics
The Effects of Vegetarian and Vegan Diet during Pregnancy on the Health of Mothers and Offspring
Vegetarian Diet during Pregnancy Is Not Associated with Poorer Cognitive Performance in Children at Age 6–7 Years
The Impact of Mediterranean Dietary Patterns During Pregnancy on Maternal and Offspring Health
Effect of Adherence to Mediterranean Diet during Pregnancy on Children’s Health: A Systematic Review
Vegetarian diet observed by pregnant women. Benefits and risks for mother and fetus
Annales Academiae Medicae Silesienis
Periconceptional Maternal Mediterranean Diet Is Associated With Favorable Offspring Behaviors and Altered CpG Methylation of Imprinted Genes
Frontiers in Cell and Developmental Biology
A Vegetarian Diet Is a Major Determinant of Gut Microbiota Composition in Early Pregnancy
Association of maternal and index child’s diet with subsequent leukemia risk: A systematic review and meta analysis
32 - Vegetarian and Plant-Based Diets in Pregnancy
Vegetarian and Plant-Based Diets in Health and Disease Prevention
A vegetable, fruit, and white rice dietary pattern during pregnancy is associated with a lower risk of preterm birth and larger birth size in a multiethnic Asian cohort: the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort study
American Journal of Clinical Nutrition
Plant-Based and Plant-Rich Diet Patterns during Gestation: Beneficial Effects and Possible Shortcomings
Advances in Nutrition
A Review of the Impact of Dietary Intakes in Human Pregnancy on Infant Birthweight
The association between diet quality and mental health during the perinatal period. A systematic review
Does maternal diet during pregnancy and lactation affect outcomes in offspring? A systematic review of food-based approaches
Relation of the Mediterranean diet with the incidence of gestational diabetes
European Journal of Clinical Nutrition
Maternal and Early Postnatal Nutrition and Mental Health of Offspring by Age 5 Years: A Prospective Cohort Study
Journal of the American Academy of Child & Adolescent Psychiatry
Maternal Nutrition and Perinatal Outcomes
Journal of Midwifery and Women's Health
The maternal Mediterranean dietary pattern is associated with a reduced risk of spina bifida in the offspring
International Journal of Obstetrics and Gynaecology
Associations of diet and physical activity during pregnancy with risk for excessive gestational weight gain
American Journal of Obstetrics and Gynecology
A Dietary Pattern Characterized by High Intake of Vegetables, Fruits, and Vegetable Oils Is Associated with Reduced Risk of Preeclampsia in Nulliparous Pregnant Norwegian Women
Journal of Nutrition
Vegetarian Diets in Pregnancy
Handbook of Nutrition and Pregnancy
Association between a Mediterranean-type diet and risk of preterm birth among Danish women: a prospective cohort study
Acta Obstetricia et Gynecologica Scandinavica