WHAT YOU EAT IS WHAT BABY GETS

By Dr Alan Lindemann

The Direct Pipeline From Your Plate to Your Baby

There is a direct pipeline between what a pregnant woman eats and what her baby receives. It is not metaphorical. It is anatomical. The placenta, the organ that connects mother and baby through the umbilical cord, transfers nutrients from the mother’s bloodstream to the baby’s bloodstream continuously, from the implantation of your baby in your uterus through delivery.

What arrives through that pipeline determines what your baby has available for building every cell, every tissue, and every organ, including the brain. The quality and completeness of your diet is the quality and completeness of your baby’s nutritional supply. What you eat is, quite literally, what your baby gets.
 

The Placenta as Transfer Station

The placenta is one of the most extraordinary organs in biology. It forms from the same fertilized egg as the baby, implants in the uterine wall, and within weeks becomes the baby’s lungs, kidneys, digestive system, and immune interface — all in one. It transfers oxygen and nutrients from the mother’s blood to the baby’s blood, removes carbon dioxide and waste products from your uterus and does all of this without allowing mother’s and baby’s bloodstreams to mix directly.

The nutrient transfer across the placenta is not only passive. It is active and selective. The placenta has specific transport mechanisms for each specific nutrient. Dedicated molecular machinery pulls glucose, amino acids, fatty acids, vitamins, and minerals from your circulation and delivers them to the baby’s circulation. Some nutrients are transferred in proportion to your intake. Others are preferentially delivered to the baby even when your own levels are low. The placenta will draw down your reserves to supply your baby.

This preferential transfer is protective for your baby in the short term. It means should your diet be imperfect, your baby will not automatically be nutritionally deprived. But preferential transfer has limits. When your reserves are depleted, your baby’s supply diminishes. For some nutrients such as docosahexaenoic acid (DHA), iodine, folate, your dietary intake is the primary determinant of what your baby receives because your reserves of these nutrients are limited.
  

When Each Nutrient Matters Most

Different nutrients matter most at different times in pregnancy, because different developmental processes have different windows of peak demand. The folate that is critical in the first four weeks of pregnancy when the neural tube is closing is needed in a different way than time the DHA that is critical in the third trimester when nerve synapses in the brain are forming rapidly. The iron that supports blood volume expansion in the second trimester is needed in a different way than the calcium that builds the fetal skeleton throughout pregnancy.

Understanding these windows is not meant to create anxiety about dietary perfection but rather to emphasize the importance of adequate nutrition throughout pregnancy, beginning before conception if possible. The pipeline needs to be consistently well supplied, not excellent just now and then.

The Nutrients that Matter the Most 

Folate — The Neural Tube Nutrient

Folate (vitamin B9) is required for DNA synthesis and cell division. In the developing embryo, folate is specifically critical for the closure of the neural tube, the embryonic structure that becomes the brain and spinal cord which occurs between days 22 and 28 after conception. This is typically before a woman even knows she is pregnant.

Neural tube defects, including spina bifida, occur when this closure is incomplete. Adequate folate before and during the neural tube closure window significantly reduces the risk. The challenge is that by the time most women begin prenatal vitamins after a positive pregnancy test, the neural tube closure window may already be complete.

Folate supplementation should begin before conception for any woman who might become pregnant. The standard recommendation is 400 to 800 micrograms daily from a prenatal vitamin, beginning at least one month before conception and continuing through the first trimester. If you are already pregnant and have not yet begun folate supplementation, start today.
 
DHA — The Brain-Building Fat

Docosahexaenoic acid (DHA) is an omega-3 fatty acid that is the primary structural fat of the brain, heart, vascular system, and retina. It is long,  polyunsaturated, and incorporated into the membranes of every neuron produced your baby produces. The brain is approximately 60 percent fat by dry weight, and DHA is the metabolically active  fat in our brains.  

The formation of synapses between neurons begins in earnest in the second trimester and peaks in the third trimester and continues into the first two years of life. During this period the demand for DHA is at its highest. The fetal brain actively accumulates DHA from your circulation and the amount available depends directly on your dietary intake. Cholesterol is another important fat your baby’s brain development and is required in mothers’ diets because unlike adults who make their own brain cholesterol in their brains, babies and infants cannot make their own brain cholesterol. 

 
The primary dietary sources of DHA are fatty fish such as salmon, sardines, anchovies, mackerel, and herring. The DHA in prenatal vitamins is typically derived from algae or fish oil. The recommended intake during pregnancy is at least 200 milligrams per day, with higher intakes from food sources providing additional benefit.

The fear of mercury in fish has led many pregnant women to avoid fish entirely during pregnancy. This is an overcorrection with real consequences. The high-mercury species such as shark, swordfish, king mackerel, tilefish, and bigeye tuna are worth avoiding. The low-mercury fatty fish such as salmon, sardines, and anchovies are among the most valuable foods available during pregnancy. The DHA benefit substantially outweighs the mercury risk at normal consumption of these low-mercury species.
  

Cholesterol — The Synapse Builder

Cholesterol has a poor reputation in general health discussions. In the developing brain, it is indispensable. Every synapse in the brain requires cholesterol for its formation and maintenance. The myelin sheath that wraps around nerve fibers and enables rapid electrical conduction is approximately 70 percent cholesterol by dry weight. Without adequate cholesterol in the mother’s diet, neither synaptogenesis nor myelination can proceed at the rates the developing brain need    .

Your baby’s brain cannot synthesize adequate cholesterol independently. It is dependent on cholesterol delivered through the placenta from your circulation. Eggs, dairy fat, and meat contribute to your cholesterol pool that supplies your baby the cholesterol it needs.

This is one of the primary reasons the egg is the most important single food in your prenatal diet. The egg yolk contains cholesterol in a form that is readily absorbed and transported. One egg per day, every day, from the first week of confirmed pregnancy through the end of breastfeeding is needed. Cholesterol is the dietary delivery mechanism for the nutrient your baby’s developing brain cannot build without.

Choline — An Overlooked Essential

Choline is a nutrient that receives far less attention than folate or DHA despite being equally critical to your baby’s brain development. It is required for the synthesis of acetylcholine, a neurotransmitter essential for memory and muscle control and for the production of phosphatidylcholine, a major component of cell membranes throughout the brain and body.

Choline is also specifically required for neural tube development, working alongside folate during the critical closure window. Women with inadequate choline during pregnancy have higher rates of neural tube defects even if they have enough folate.

The recommended amount of choline during pregnancy is 450 milligrams per day, an amount most prenatal vitamins do not provide in this quantity. The best dietary source is the egg yolk, which contains approximately 150 milligrams of choline per egg.  

Iron — The Oxygen Carrier

Iron is required for the production of hemoglobin, the protein in red blood cells that carries oxygen. During pregnancy, blood volume expands by approximately 40 to 50 percent above pre-pregnancy levels. This expansion requires a proportional increase in red blood cell production, which requires iron. At the same time, your growing baby and placenta have their own iron requirements.

Iron deficiency during pregnancy is the most common nutritional deficiency worldwide. In the mother, it produces fatigue, reduced exercise tolerance, and impaired immune function. In the baby, iron deficiency during the critical window of brain development, particularly the third trimester and first two years of life, is associated with impaired cognitive development and behavioral difficulties that persist beyond infancy.

The recommended iron intake during pregnancy is 27 milligrams per day, nearly double the requirement for women who are not pegnant. Most prenatal vitamins contain this amount. Iron from animal sources, from meat, poultry, and fish, is absorbed more efficiently than iron from plant sources. Vitamin C consumed alongside iron-rich foods enhances iron absorption.
 

Calcium — The Skeleton Builder

Calcium is required for your baby’s bone and tooth development throughout your pregnancy, with the need for calcium increasing in your third trimester as your baby’s skeleton mineralizes. If your calcium intake is inadequate, the placenta will draw calcium from your bones to supply your baby, a protective mechanism for the baby that comes at a cost to your long-term bone density.

The recommended amount of calcium during pregnancy is 1,000 milligrams per day. Dairy products are the most concentrated dietary source. Fortified plant milks, canned fish with bones, and dark leafy greens also contribute. Most prenatal vitamins contain only a portion of the the daily amount of calcium required, making it essential to be sure your diet includes sources of calcium.
 

Iodine — The Thyroid Nutrient

Iodine is required to produce thyroid hormones to regulate metabolism for normal fetal brain development. Iodine deficiency during pregnancy is the leading preventable cause of intellectual disability worldwide. Even mild iodine deficiency that does not produce overt disease in the mother can impair fetal cognitive development.

Iodine is frequently omitted from prenatal vitamins. Check the label of your prenatal vitamiin specifically for iodine. The recommended level of iodine during pregnancy is 220 micrograms per day. Iodized salt and dairy products are the primary dietary sources in the United States. Seafood is also a good source.

The Prenatal Vitamin is a Supplement

The prenatal vitamin is a supplement, not a substitute for a nutritious diet. A prenatal supplement cannot compensate for a poor diet. What a prenatal supplement does is fill the gaps, the nutrients that are difficult to obtain in adequate amounts from diet alone or are specifically required in quantities higher than what a typical diet provides.