Vegan diet during pregnancy can be harmful to mothers and their babies

COPENHAGEN, Denmark — Women who follow a vegan diet during pregnancy could be putting themselves and their babies at risk for health problems, according to new research. A study by Danish researchers finds that vegan mothers face higher odds of developing preeclampsia, while their babies are more likely to be born with a lower birth weight.

In recent years, the wave of veganism has been sweeping across western societies, driven by environmental, ethical, and animal welfare concerns. This plant-based lifestyle, once a fringe movement, is now a significant part of our dietary landscape. Denmark, for instance, has seen veganism rise from under one percent in 2010 to about three percent in 2022, particularly among young adults and expectant mothers. But what does this shift mean for pregnancy outcomes?

The Danish National Birth Cohort, encompassing over 91,000 women, offers some answers to this question. This study aimed to unravel the dietary composition of various plant-based diets during pregnancy and their associations with birth outcomes.

Conducted between 1996 and 2002, the study enrolled 91,381 pregnant women, covering approximately 35 percent of all births in Denmark during that period. Study authors meticulously interviewed the participants, and analyzed their diets using a comprehensive Food Frequency Questionnaire.

The team categorized women following plant-based diets as fish/poultry vegetarians, lacto/ovo-vegetarians, or vegans. The study then compared these groups with omnivorous mothers to assess differences in birth weights, gestational lengths, and pregnancy complications.

đŸ”‘ Key Findings:

  • Vegans, lacto/ovo-vegetarians, and fish/poultry vegetarians generally consumed less energy and protein compared to omnivores. However, their intake of carbohydrates was higher. Interestingly, when the study included dietary supplements in the results, most nutrients met recommended intakes, except for vitamin D in vegans.

 

  • Vegan mothers had infants with lower average birth weights and a higher prevalence of low birth weight compared to meat-eating mothers. However, researchers did not observe any significant differences in birth outcomes between fish/poultry vegetarians, lacto/ovo-vegetarians, and omnivorous mothers, except for a slightly higher prevalence of anemia in the first two groups.

 

  • All plant-based diet groups showed a low prevalence of gestational diabetes. However, vegan mothers exhibited a higher prevalence of preeclampsia, a pregnancy complication characterized by high blood pressure.

The findings suggest that while most plant-based diets do not adversely affect pregnancy outcomes, strict vegan diets might pose certain risks, particularly related to lower birth weights and preeclampsia. This could be attributed to lower protein intake and potential nutritional deficiencies, despite supplementation.

It’s important to note that the number of vegans in the study was relatively small, so these findings should be interpreted with caution. Additionally, the dietary habits of vegans in the late 1990s and early 2000s might differ from today’s practices.

This extensive study sheds light on the complex relationship between plant-based diets and pregnancy outcomes. While it provides valuable insights, it also underscores the need for further research to refine dietary recommendations for expectant mothers following vegan diets.

Embracing a plant-based lifestyle can be a healthy choice for many, but when it comes to pregnancy, it’s crucial to ensure a well-balanced diet to support both maternal and fetal health. As the popularity of veganism continues to rise, more comprehensive studies will be vital in guiding future public health guidelines and personal dietary choices.

The study is published in the journal Acta Obstetricia Et Gynecologica Scandinavica.