Everybody knows that you should take a prenatal vitamin if you are expecting a new baby. But why? What is the prenatal vitamins mechanism of action? Well, different vitamins and minerals in a prenatal vitamin work in different ways. There is no one single thing that makes it work. The main point of a prenatal vitamin is to make sure that your body can provide all the essential nutrients for your new baby.
These days many people are skeptical of supplements, This might lead you to question whether you even need a prenatal vitamin, especially if you are a healthy eater. However, you certainly do, and there is a reason your doctor recommends it. We’ve already discussed which nutrients you should look for, and at what levels, but how do they work? Read on to find out which are the most important essential nutrients to look for in a prenatal vitamin, and how they work to help optimize the health of your developing baby.
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Here’s what we’ll cover:
- Folate: A critical B vitamin for pregnancy
- Omega-3 DHA for healthy brain development and full-term pregnancy
- Choline – the new essential nutrient on the scene
- Iodine: Many women may be deficient in this critical nutrient and not know it
- Vitamin D – For more than just healthy bones
- Lutein for eyes and brain
Folate: A critical B vitamin for pregnancy
Folate is one of the B vitamins, and is important for what’s called the “methylation” pathway. It’s important in moving carbons around from one molecule to another. Moving carbons sounds mundane, but in fact, it’s one of the most essential functions of life. The DNA in your genes that provides the code for your exact genetics depends upon this methylation process.
With regard to pregnancy, folate is a critical vitamin. Folate is the main reason that doctors recommend you take a prenatal vitamin in the first place. Folate and the methylation pathways that it supports are critical for the early formation of the central nervous system. In the first few weeks of pregnancy, the baby’s “neural tube” has to close to form the spinal cord. If you have a folate deficiency, the neural tube can fail to close, causing a neural tube defect like Spina Bifida.
Folate is so important for pregnancy that in 1998 the FDA created a mandatory fortification policy to require the addition of folic acid to wheat flour. Since then, the rate of neural tube defects as decreased by 35%. If you tend to skip grain-based foods, you should definitely take a folate-containing multivitamin. And even if you do get a decent amount of folate in your diet, a prenatal vitamin is good insurance.
Another important thing to know is that some people have a gene variant that affects one of the important enzymes in folate metabolism, called MTHFR. The good news is that some of the most common genetic tests like the ones from 23andMe and Orig3n can detect this variant if you have it. Be sure to check out our article on the MTHFR gene variant and the importance of selecting a product containing methylfolate, like the ones below:
Omega-3 DHA for healthy brain development and full-term pregnancy
Have you heard of docosahexaenoic acid? We call it “DHA” for short and it’s a vital polyunsaturated fatty acid (or PUFA) that is required for the development of your baby’s brain. Your body can actually make DHA from a precursor PUFA called alpha-linolenic acid (ALA), but most people don’t consume enough to make a significant amount of DHA.
DHA is an important component of cell membranes in the central nervous system.
Its mechanism of action relates to the fact that it has “unsaturated” bonds in the fatty acid chain. DHA is a long molecule, and the unsaturated bonds allow it to twist and turn. Basically, it helps keep the membranes in your nervous system fluid. This is important to enable the adaptation and growth of new pathways in the brain, and a great deal of research has demonstrated its importance for your baby’s developing brain.
More recently, it’s been found that DHA supplementation can even lower the risk of preterm birth. It’s not just about the brain development of your baby, taking a DHA supplement can even decrease the risk of delivering early. This is especially important since so many women don’t consume the recommended amounts of fish. What’s interesting is that the level of DHA necessary for this effect was 500 mg/day or more. Current recommendations and many prenatal supplements only deliver 200 mg of DHA.
Check out these high-quality options to boost your DHA intake:
Choline – the new essential nutrient on the scene
Have you heard about choline? It’s the latest essential micronutrient on the scene – in fact just recently FDA gave the green light for it to get a daily value on the supplement facts panel. The mechanism of action of choline is related to its ability to donate methyl groups – that is “1-carbon” molecules. These groups are essential in the control of a variety of cellular processes, especially those having to do with expression and modification of genes – otherwise known as “DNA methylation.”
Although it’s technically not a vitamin, it has a similar function in the body as some of the B vitamins, so sometimes its considered part of the B vitamin family.
The thing about choline is that it’s hard to get enough from food, and because it’s new on the scene, there aren’t many prenatal supplements that have it. Here are a few options that can help you boost your choline intake:
Iodine: Many women may be deficient in this critical nutrient and not know it
Iodine is a key nutrient for the development of the central nervous system in an unborn baby. Iodine’s mechanism of action in prenatal vitamins has to do with its essential role in the production of thyroid hormone, which contains an iodine molecule as part of its structure.
A recent and very influential study published in Lancet found that children born to women with mild to moderate iodine deficiency tended to have lower cognitive functioning up to age 9. As a result, recent guidelines from the American Academy of Pediatrics recommend that all pregnant and breastfeeding women take a supplement containing iodine.
The problem is that, even in the face of these recommendations, many prenatal vitamins, especially gummies, don’t contain iodine at all. The products below have good amounts of iodine and would be a good choice:
Vitamin D – For more than just healthy bones
Vitamin D is an essential nutrient but it can also be made in the skin by exposure to sunlight. It actually acts more like a hormone than a typical vitamin. Its main function is to help regulate the absorption of calcium. This is why a lack of vitamin D can result in rickets which is the bowing of the leg bones. However, vitamin D is also involved in many other biological processes far beyond bone, which is why it’s a critical component in prenatal vitamins mechanism of action.
There are two different types of vitamin D, vitamin D3, which is the form that’s made in your skin, and vitamin D2 which comes from plants, yeast or fungi and has a similar biological action. There is some research to indicate that vitamin D2 may not be quite as potent as vitamin D3, but generally speaking, it’s an OK alternative for vegans.
Vitamin D is not active by itself, your body needs to convert it in two steps in order for it to be active. First, your liver converts it to a more water-soluble form that can circulate in the blood: 25-hydroxyvitamin D. If you get a lab report for vitamin D, this is what you will see. Then it needs to get converted to the active form, 1,25-hydroxyvitamin D, also known as calcitriol, by the kidneys. This active form has many physiological effects because it interacts with the “vitamin D receptor” which affects the expression of many different genes related to calcium absorption, inflammation and many other biological processes.
In pregnancy, low blood levels of vitamin D levels have been associated with high blood pressure during pregnancy, gestational diabetes, and low birth weight in babies. In fact, supplementation with vitamin D has been shown to reduce the risk of having a low birth weight baby. Unfortunately, most pregnant women don’t get enough vitamin D. So just remember, next time you are letting it all hang out at the beach, you are actually doing something great for your baby! And if you don’t get a lot of sun, here are two options for you to boost your vitamin D level if your prenatal vitamin isn’t enough:
Lutein for eyes and brain
Lutein is a yellow carotenoid found in green leafy vegetables. It functions in the body as an antioxidant. Recent research indicates that lutein is actually preferentially accumulated in the brain. According to some studies in primates, it’s even located in the same areas where DHA is found. This suggests that lutein may have a protective effect on DHA.
Lutein is also important for eye development. It’s found in the macula – the central part of the retina where all the concentrated light hits. Because there are so many nerves concentrated in this part of the eye, lutein protects this area from the oxidative stress caused by all this light exposure.
Importantly, most prenatal vitamins don’t contain lutein. If your prenatal doesn’t have it, there are a few options you can also look into:
Now that you have some ideas on the prenatal vitamins mechanism of action, you can make some more informed choices about which supplements you choose during your pregnancy.