Key Nutrient Needs during Pregnancy
Protein is the major structural component of all cells, and during pregnancy whole body turnover increases as the fetus, uterus, placenta, blood volume, amniotic fluid, and maternal skeletal muscle demands are met .
Fat is a major source of energy and aids in the absorption of fat- soluble vitamins and carotenoids. The developing brain of the fetus requires large amounts of docosahexaenoic acid (DHA), so adequate supplementation of essential fatty acids is recommended during pregnancy .
Vitamin A is important for gene expression and cell differentiation in the developing fetus .
Vitamin D maintains serum calcium and phosphorus concentrations and serves as a potent antiproliferative and prodifferentiation hormone .
Vitamin E is an antioxidant that prevents lipid peroxidation, especially for polyunsaturated fatty acids within the membrane phospholipids and plasma lipoproteins . Blood concentrations increase during pregnancy and placental transfer appears constant.
Vitamin K is used as a coenzyme in protein synthesis for blood coagulation and bone metabolism. Data about its role during pregnancy is limited .
Thiamin is a coenzyme in metabolism of carbohydrates and branched-chain amino acids. The increased requirement during pregnancy is used for energy production both maternally and by the fetus .
Riboflavin is a coenzyme in oxidation-reduction reactions with additional needs during pregnancy to meet the growth and energy utilization by the fetus .
Niacin is required to form nicotinamide adenine dinucleotide and nicotinamide-adenine dinucleotide phosphate, plus biosynthesis of fatty acids and steroids .
Vitamin B6 is involved in the metabolism of amino acids, glycogen, and sphingoid bases. B6 coenzymes are needed for heme synthesis and transsulfuration breakdown of homocysteine to cysteine .
Folate functions in the metabolism of nucleic and amino acids, DNA synthesis, and cell division. Inadequate concentrations of folate can result in megablastic anemia .
Vitamin B12 is a coenzyme for the metabolism of fatty acids and in methyl transfer reactions. Absorption may decrease during pregnancy and vegan diets especially need supplementation of Vitamin B12 .
Pantothenic acid is a component of coenzyme A but little information is available about needs during pregnancy .
Biotin functions in carboxylation reactions with D-methylmalonyl- coenzyme A formation, which is dependent on adequate biotin .
Choline is a precursor to acetylcholine, phospholipids, and betaine. It is synthesized in the body but may be inadequate under certain conditions like pregnancy since large amounts are delivered to the fetus during pregnancy .
Sodium and chloride maintain the extracellular volume and serum osmolality, which do not usually require supplementation during pregnancy.
Potassium has influence on neural transmission, muscle contraction, and vascular tone. The adequate intake is the same for pregnant and nonpregnant women . The high level of progesterone may help conserve potassium in pregnancy.
Calcium contributes to the strength of bones and teeth, along with mediating vascular contractions, vasodilation, muscle contraction, nerve transmission, and glandular secretions. Due to increased absorption efficiency in pregnancy, increased supplementation is not recommended unless bone degradation has occurred prior to pregnancy .
Phosphorus is essential in all tissues but due to enhanced absorption during pregnancy, no additional supplementation is recommended .
Magnesium is required in over 300 enzymes with the fetus demanding a significant amount. That demand usually requires additional supplementation .
Chromium improves insulin action but its need during pregnancy has not been accurately determined .
Copper is a component of metalloenzymes for reduction of oxygen. The fetus must accumulate copper during pregnancy and so intake of dietary and supplemental sources of copper need to be encouraged .
Fluoride can inhibit the initiation and progression of dental caries and stimulate new bone development. It crosses the placenta and gets incorporated into primary teeth. Supplementation during pregnancy is not supported .
Iodine is essential for thyroid hormones and regulates protein synthesis. Thyroid hormone is critical for myelination of the central nervous system and is very active during the prenatal period. Lack of iodine damages the developing brain and its deficiency leads to mental retardation, hypothyroidism, and goiter .
Iron is a component of proteins—heme, iron-sulfur, iron storage, and transport and iron-activated enzymes. Lack of iron during pregnancy can lead to perinatal mortality. Maternal anemia is also associated with premature delivery and low birth weight. The fetal need for iron is met at the expense of maternal stores so most women will need supplementation during pregnancy .
Manganese is needed for bone and amino acid metabolism. Data is very limited on its need in pregnancy .
Molybdenum is a cofactor in numerous enzymes like sulfite oxidase, xanthine oxidase, and aldehyde oxidase. No data is available about needs during pregnancy .
Selenium is important to regulate thyroid hormone action, defend against oxidative stress, and regulate redox status of vitamin C. The fetus stores selenoproteins during development so additional supplementation is recommended .
Zinc has regulatory function in over 100 enzymes. As the fetus develops, it stores zinc throughout the pregnancy and requirement increases substantially .
Major Foods and Nutrient Sources during Pregnancy
Sunlight: vitamin D—4,000 IU supplement daily Eggs: protein, choline, lutein, and zeaxanthin Salmon: protein, omega-3 fatty acids—eicosapentaenoic acid (EPA) and DHA
Dairy: protein, B vitamins, zinc (yogurt or kefir are better tolerated than whole milk)
Sweet potatoes: beta carotene, fiber
Greens: cooked spinach, asparagus for folate, fiber, vitamin K Beef and chicken: protein, B vitamins, iron Grass-fed beef liver: vitamin B12, iron
Avocados: potassium, B vitamins, folate, monounsaturated fatty acids
Papaya: folate, beta carotene, vitamin C