Plant-Centric Nourishment During Pregnancy

A plant-based diet generally involves renouncing meat, fish, and animal products. However, the scope of the exclusions may vary, so we can distinguish between a lacto-vegetarian diet (most often referred to as vegetarian), which eliminates the consumption of flesh, fish, and seafood, while allowing the use of dairy products and eggs, and its two variations: dairy diet (it does, however, plan to eat protein, but renounces animal diet) and egg diet (more than egg-based diets). A diet that consists exclusively of vegetable ingredients from pregnant women and contains all the components of plant health foods from the diet of vegans and vegans. However, the applied nutritional model is often somewhere between all the described types. According to the statement of the American Academy of Nutrition and Dietetics, a well-planned plant-based diet (both vegetarian and vegan) is safe to use at every stage of life – including during pregnancy and lactation (V. Melina et al. 2016). The data on the course of pregnancy and the health of newborns of women on a vegetarian and vegan diet compared to toddlers of mothers eating traditionally are limited. However, based on available research, no evidence has been found that the use of the plant model is associated with an increased risk of complications and side effects that pose a threat to mother and child. It has been noted, however, that children of vegetarians and vegans more often have a lower birth weight – these are not, however, dangerous values for health and life. This could be related to a lower intake of protein and some nutrients by pregnant women, which additionally indicates how important proper meal planning is (G. B. Piccoli et al. 2016; S. F. Yisahak et al. 2021). So what should one pay attention to and how can one meet the demand for nutrients?

A pregnant woman's energy needs change over time. In the first trimester they increase by 85 kcal per day, in the second trimester by 285 kcal per day, and in the third trimester by 475 kcal per day compared to pre-pregnancy values (M. Jarosz et al. 2020). It may be useful for the additional energy to come from high-quality foods, such as protein, iron, or folic acid. As for the frequency of meal consumption, it may be beneficial to eat smaller portions more often. In the first trimester, this practice can be helpful in reducing nausea and vomiting. In the following trimesters, it may provide an opportunity to increase calorie intake without increasing portion sizes to a difficult-to-handle size, as plant-based dishes often have a larger volume than traditional meals. However, it is important to consider the health status, habits, and preferences of the future mother.

The increase in calorie requirements during pregnancy is also linked to changes in the proportion of various nutrients in the diet. Protein demand increases in this period to 0.98-1.2 g/kg of actual body weight per day, while it is about 0.73-0.9 g outside of pregnancy. It is important to note that this refers to the current body weight, which means that the amount of protein that needs to be consumed will gradually increase as weight increases throughout pregnancy. Protein sources in a plant-based diet should primarily consist of legumes and their derivatives such as tofu, tempeh or soy products. In addition to protein, they also contain other nutrients such as iron and zinc. If legumes are poorly tolerated, it may be beneficial to consume them in the form of pastes, soups, or savory snacks. Other protein sources in a plant-based diet are nuts and seeds as well as grains such as oatmeal, quinoa or buckwheat. In order to ensure the provision of all necessary amino acids, it is advisable to combine different food groups in a meal. Women who follow a vegetarian diet can also obtain protein from eggs and dairy products, but they should avoid raw or semi-raw eggs and products based on unpasteurized milk that have not been thermally treated. During pregnancy, it is also recommended to add fat to the diet. In the first trimester, this is about 3 g/day, in the second 10-11 g, and in the third 16-19 g. Fat can be provided by adding nuts, seeds, or oil to meals. In this period, the consumption of hardened vegetable fats should be avoided, which can have negative effects on fetal development. The demand for carbohydrates does not change during pregnancy and they make up the remainder of the diet, providing 45-65% of the total energy intake of the menu.

During pregnancy, in order to provide the developing organism with optimal conditions for healthy growth, the body's demand for many nutrients changes. Using a plant-based diet can also present some challenges in terms of supplying essential substances. Therefore, it is advisable to consider the key micronutrients in the diet of growing plants and vegetarians, as well as the ways in which they are supplied to the body. The first of these ingredients is iron, the demand for which increases during pregnancy by half - from 18 mg/day to 27 mg/day. Iron from plant sources is harder to absorb than iron from animal products, so it is important to use proper processing techniques and to compose meals in a way that allows for optimal absorption. For example, one can soak seeds and nuts before consuming, choose full-grain bread based on sourdough, and avoid combining products rich in calcium with iron-rich products. Coffee, tea, and cocoa should also be avoided during meals. To ensure an adequate intake of iron in a plant-based diet, it is important to include legumes, nuts and seeds, some grains (such as buckwheat, millet, amaranth), as well as vegetables (parsley, broccoli) in the diet.

Pregnancy is a time when it is necessary to provide certain nutrients in the form of medications or supplements. According to the recommendations of the Polish Society of Obstetricians and Gynecologists, healthy pregnant women should take: - folic acid at 0.4 mg/day before conception and 0.4-0.8 mg/day during pregnancy (depending on the stage of pregnancy) - docosahexaenoic acid (DHA) at 200 mg per day for all pregnant women, and for those who consume small amounts of fish (e.g. vegetarians and vegans), the dose should be increased up to 1000 mg/day - vitamin D at 1500-2000 IU/day - iodine in an amount of 150-200 µg/day (M. Zimmer et al. 2020). The Society also recommends monitoring blood parameters (hematology and ferritin concentration) during pregnancy to prevent the development of iron deficiency anemia. In case of its occurrence, supplementation should also be introduced (M. Zimmer et al. 2020). In addition – as mentioned earlier – women on a vegetarian or vegan diet should supplement vitamin B12.

The adoption of a plant-based diet during pregnancy can be deemed safe, provided that the menu is appropriately balanced, which entails providing a suitable supply of calories and nutrients, along with the administration of suitable supplements. This necessitates commitment, nutritional knowledge, and skills. Hence, it is advantageous for women adhering to a plant-based diet to prepare for these challenges during the pregnancy planning phase and to consistently monitor their health and that of their child.