During pregnancy, your body is undergoing incredible changes every day to grow your baby and prepare for delivery. These complex processes are fueled by many nutrients that provide essential building blocks in utero and support a healthy pregnancy. Below is a list of ten key nutrients–including their role in pregnancy, baby’s development, the recommended daily intake, and some significant food sources.
Choline
Choline has gained a lot more attention in recent decades with more abundant research on its role in the nervous system, brain development and gene expression. Choline works alongside folate to support many metabolic functions, including various aspects of your baby’s development during pregnancy. Interestingly, choline also works together with DHA to increase delivery of this beneficial fat to your baby across the placenta (read more about DHA at the end of this blog). It’s recommended to increase choline intake to at least 450 mg/day during pregnancy. The richest food sources of choline are eggs (specifically the yolk), meat and dairy products. Choline is more limited in plant sources, but can be found in foods such as potatoes, kidney beans, and quinoa.
Folate
The importance of folate is commonly discussed due to its role in the development of baby’s brain and nervous system. Folate performs similar functions as choline, with adequate intake helping to prevent neural tube defects such as spina bifida and supporting production of neurotransmitters. Folate is also important to maintain healthy hemoglobin levels during pregnancy, when blood volume is rapidly increasing. Recommended intake increases significantly to at least 600 mcg/d, compared to 400 mcg/d in non-pregnant women. Dark leafy greens such as spinach and kale, as well as beef liver and legumes are some of the highest food sources of folate.
Vitamin B12
Similar to the nutrients above, vitamin B12 serves an important role for several aspects of your baby’s growth, such as building DNA and supporting brain development. You also require enough vitamin B12 to maintain the health of your red blood cells and nervous system. Only animal products have naturally occurring vitamin B12, with the richest food sources being dairy products, meat, fish, eggs and poultry. Vitamin B12 is commonly added to certain plant-based foods such as breakfast cereals, soy milk and nutritional yeast; though for vegan folks, additional supplementation is usually recommended. Recommended intake is currently 2.6 mcg per day during pregnancy.
Selenium
Selenium serves as an antioxidant and anti-inflammatory supporting the immune system as well as liver function. The process of converting thyroid hormones to their active form in the body is through selenium-dependent enzymes, working together with iodine to promote healthy thyroid function for both you and your developing baby. Major food sources of selenium include seafood, poultry, eggs and organ meats. One of the richest plant sources of selenium is Brazil nuts, with only 1-3 nuts meeting the recommended intake of 60 mcg per day for pregnant women.
Iodine
As mentioned above, adequate iodine intake is important to maintain healthy thyroid function as well as supporting brain development in your baby. Production of thyroid hormones increases by ~50% during pregnancy, creating a higher demand for iodine as an essential building block. Recommended intake is 220 mcg per day during pregnancy compared to 150 mcg/d for non-pregnant women. Iodine-rich foods include seafood (including seaweed), eggs, dairy, and fortified salt.
Vitamin D
Vitamin D is a powerful nutrient extending benefits to various functions in the body – including bone mineralization, immunity, heart health, and more. Adequate vitamin D levels help prevent pregnancy complications as well as building strong bones for your baby. The primary way to get vitamin D is actually from sun exposure, as it’s the only vitamin to be synthesized in the skin from UV rays. While there are some vitamin D rich foods – such as salmon, eggs, and organ meats – it can be challenging to obtain enough vitamin D from the diet alone. Nowadays with most people spending a majority of their time indoors and (rightfully so) more use of sunscreen, vitamin D deficiency is common. Especially for folks in the Pacific Northwest, many months of the year there are gloomy skies, less time spent outside, and the sun’s position during the winter and spring does not allow as much exposure to UV-B rays even without cloudcover. The current recommendation for vitamin D intake during pregnancy remains the same as non-pregnant women at 15 mcg per day, though many need to supplement more than this to achieve normal vitamin D levels. It’s helpful to include vitamin D in your prenatal lab work and work with a dietitian to help determine adjustments to your supplementation if needed.
Calcium
Along with adequate vitamin D intake, calcium supports the development of baby’s bones as well as increased storage of calcium in your own skeleton, which is thought to help prepare the body for lactation. Calcium needs do not increase during pregnancy unlike other minerals listed here – in fact, the body actually increases absorption of calcium from the intestine during this time. The daily calcium goal remains at 1000 mg per day, with major food sources being dairy products or fortified dairy alternatives, tofu, leafy green vegetables and fish with the bones (such as sardines).
Iron
Iron needs are substantially higher during pregnancy due to a rapid increase in blood volume and to support your growing baby and placenta. Recommended intake of iron is 27 mg per day during this time – compared to 18 mg per day in non-pregnant women. Animal sources of iron (or “heme iron”) such as meat, chicken and fish are typically easier for the body to absorb. However, there are several plant-based (“non-heme”) sources as well such as lentils, tofu, and pumpkin seeds. When consuming both heme and non-heme iron foods, it’s helpful to eat alongside a source of vitamin C (such as citrus fruits, tomatoes, bell peppers, and vinegar) to increase absorption. It’s also recommended to limit high-calcum foods (such as a glass of milk) or calcium supplements with iron-rich meals, as these minerals compete with each other for absorption.
Glycine
Glycine is an amino acid (the smallest unit of protein) that helps build the most abundant protein in the body – collagen. Many are familiar with the benefits of collagen for hair, skin and nails; so when you think about all of the growth taking place for you and your baby, it makes sense that this protein plays an important role during pregnancy. In non-pregnant individuals the body is able to produce enough glycine on its own regardless of the diet. However, due to the development of your baby, as well as your uterus and placenta, dietary glycine becomes essential to meet increased demands during pregnancy – especially throughout the 3rd trimester. There is currently no established recommendation for glycine intake during pregnancy, but aiming to include a variety of glycine-rich foods will help meet your needs. The most abundant sources come from animal products such as slow-cooked tough cuts of meat, meat on the bone, bone broth, and collagen or gelatin powders. Some plant sources are sesame seed flour, spirulina algae, pumpkin seeds, beans and spinach.
Omega 3 fats
Omega 3 fats such as docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and alpha-linolenic acid (ALA) are essential fats that must be consumed from the diet to obtain adequate amounts. DHA is considered the most important during pregnancy for its role in baby’s brain and eye development, while EPA works together with DHA to improve transfer across the placenta. The richest food source of DHA are fatty fish such as salmon and sardines, and major health organizations recommend eating at least 8-12 oz lower mercury fish per week. DHA can also be found in some dairy products, eggs, and meat depending on what the animal is being fed. ALA is converted in very small amounts to DHA and EPA in the body, but on its own provides benefits for heart health. ALA is found most abundantly in plant sources such as chia, flaxseeds and walnuts. While there is no set recommendation for DHA intake during pregnancy, many sources mention aiming for at least 300-600 mg of DHA daily from food and/or supplementation. For vegan or vegetarian parents that abstain from animal products, there are now DHA/EPA supplements made from algae that can make a good alternative.
But wait, doesn’t my prenatal vitamin cover me during pregnancy?
While it can be challenging to meet your increased nutritional needs during pregnancy via diet alone, many prenatals do not contain enough of certain vitamins or minerals to ensure adequate intake, and the benefits of nutrition from the food you eat goes beyond individual vitamin and mineral content. For example, many prenatals contain very little choline (if at all) while choline-rich foods such as eggs also provide many other benefits – such as healthy fats, protein, folate, antioxidants, selenium and iodine. The matrix of nutrients from food often work together to support absorption and various functions within the body.
It is recommended to take prenatal supplements during pregnancy to help address potential gaps in micronutrient intake and prevent nutritional depletion, especially if you have a history of deficiency or certain dietary limitations. Though as always, nutrition supplements are intended as a complement to a nutrient-dense diet, not a replacement. It’s helpful to meet with a dietitian specializing in pregnancy to help determine which supplements may be recommended for you, pending your unique situation and health needs.
Sources:
Alexander EK, Pearce EN, Brent GA, Brown RS, Chen H, Dosiou C, Grobman WA, Laurberg P, Lazarus JH, Mandel SJ, Peeters RP, Sullivan S. 2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum. Thyroid. 2017 Mar;27(3):315-389. doi: 10.1089/thy.2016.0457. Erratum in: Thyroid. 2017 Sep;27(9):1212. doi: 10.1089/thy.2016.0457.correx. PMID: 28056690.
Greenberg JA, Bell SJ, Guan Y, Yu YH. Folic Acid supplementation and pregnancy: more than just neural tube defect prevention. Rev Obstet Gynecol. 2011 Summer;4(2):52-9. PMID: 22102928; PMCID: PMC3218540.
Khayat S, Fanaei H, Ghanbarzehi A. Minerals in Pregnancy and Lactation: A Review Article. J Clin Diagn Res. 2017 Sep;11(9):QE01-QE05. doi: 10.7860/JCDR/2017/28485.10626. Epub 2017 Sep 1. PMID: 29207789; PMCID: PMC5713811.
