I learned that there will be a new addition to my family because one of my cousins is pregnant. After hearing the news, I called my cousin to congratulate her and her partner, and she discussed her excitement in being able to eat exceptionally large portions of food because she is now “eating for two.” When I heard this statement, I immediately informed my cousin of my concern with her nescience on healthy eating patterns during pregnancy, and I begin to wonder about the lack of knowledge some pregnant women have on their nutritional requirements during gestation. So, I created this blog post to provide a paucity of information on nutritional needs for pregnant women during gestation.

Two common dietary misconceptions about pregnant women are pregnant women should “eat for two” people and avoid consuming fish. I have provided a concise explanation for why each of these statements are incorrect below.

Misconception 1: Pregnant women can consume a larger amount of calories because they are “eating for two.”

Pregnant women do need to consume more calories during their pregnancy because they are providing nutrients for themselves and their offspring, but the number of excess calories needed for a healthy pregnancy is not as large as most people assume. The increased caloric intake of pregnant women is often divided into the three trimesters of pregnancy. During the first trimester, a pregnant woman with normal BMI (between 18.5 and 24.9) does not need to consume any additional calories because her digestive system increases the amount of absorption of some nutrients and decreases her rate of digestion to allow for more nutrient absorption. Although the first trimester of pregnancy does not require a greater caloric intake, pregnant women should consume 340 more calories (than she consumed prior to her pregnancy) from nutritionally dense foods (complex carbohydrates, polyunsaturated and monounsaturated fats, fiber, protein, etc.) in the second trimester. The third trimester of pregnancy requires an extra 450 calories than a pregnant woman with a normal BMI consumed prior to her pregnancy; this means a pregnant woman only needs to consume 110 more calories than she consumed during her second trimester. While pregnant women need to consume more calories during their second and third trimesters, the “eating for two” statement implies that pregnant women should consume a greater amount of calories than the actual caloric requirements for pregnancy, leading to overeating and excessive weight gain during gestation.

Misconception 2: Pregnant women should avoid consuming fish during pregnancy

There is a concern for pregnant women consuming fish because fish absorb mercury into their bodies where the mercury is then converted into methyl mercury, a compound causing brain development problems in infants and children. According to a study published in the Archives of Pediatrics and Adolescents Medicine Journal, consuming fish during pregnancy has beneficial effects. The eight-year long study tested maternal hair samples ten days postpartum to determine their mercury exposure during their pregnancy and gathered data via food frequency questionnaires to determine their fish consumption during pregnancy. Study questionnaires were then completed to collect data on the the inattentive and impulsive behaviors of the mothers’ infants when the infants were two weeks old and during the infants’ eight-year examination. The results of the study are pregnant women who were exposed to low levels of mercury prior to their pregnancy had children with a greater risk of Attention Deficit/Hyperactivity Disorder (ADHD)- related behavior, but the consumption of fish two times or less per week during pregnancy protected the children against ADHD-related behavior. The high concentration of DHA in fish is also a reason to include it in a pregnant woman’s diet (see my previous blog post to learn more about DHA).

Before believing common misconceptions about nutrition during pregnancy, please consult a knowledgeable healthcare advisor about dietary intake before, during, and after pregnancy.

Works cited:

  1. Paul, Annie. “16 Pregnancy Myths.” Meredith Women’s Network, n.d. Web. 10 Mar. 2016. 
  2. Blake, Joan Salge. “Life Cycle Nutrition: Pregnancy through Infancy.” Nutrition & You. Third Edition ed. San Francisco: Pearson Benjamin Cummings, 2008. 525-38. Print.
  3. ” Learn About Mercury and Its Effects.” Natural Resources Defense Council, n.d. Web. 11 Mar. 2016. 
  4. Sagiv, Sharon K., Sally W. Thurston, David C. Bellinger, Chitra Amarasiriwardena, and Susan A. Korrick. “Prenatal Exposure to Mercury and Fish Consumption During Pregnancy and Attention-Deficit/Hyperactivity Disorder–Related Behavior in Children.” Arch Pediatr Adolesc Med Archives of Pediatrics & Adolescent Medicine 166.12 (2012): 1123. Web. 11 Mar. 2016.