Prenatal Vitamin Guide

By Maia James, with research and recommendations by Michael Hopkins, PhD

Important CYA Statement
With this guide in particular, I feel like it’s SUPER important to stress that we aren’t doctors. (Well, Michael is actually a doctor—he has his PhD—just not THAT kind of doctor). Please consult with yours before taking our advice!

I’ve been trying to write this guide to help my pregnant or TTC readers choose the best organic prenatal vitamins for literally five years.

Every time I began researching, I quickly became intimidated by, well, the science of it all. Luckily, my best friend is a brilliant scientist, so he joined me in this effort and I am thrilled to finally present you with our Healthy Prenatal Vitamin Guide!

Best Overall Prenatal

Ritual Essential Prenatal

Are Prenatal Vitamins Even Necessary?

There is widespread consensus that the most essential prenatal nutrients are:

1. Folate (for neural tube closure)
2. Calcium (for bone development)
3. Iron (for oxygenation of blood)
4. Vitamin D (for healthy bones, teeth, skin, and vision)

In addition, there is emerging data to support a growing list of other nutrients that are also particularly important during gestation and should therefore be taken into account as well. These include choline, omega-3 fatty acids, and vitamin A.

You can learn more about all of these nutrients, and whether or not you may be deficient in some of them, in this post.

(You will of course find plenty of data to support the importance of ALL essential nutrients during pregnancy, but our goal with this guide was to identify the most important items to be added in supplement form to ensure proper fetal development.)

This will come as a surprise to no one, but the best way for all of us to receive our nutrients is from our food, period, and prenatal vitamins should not be viewed as a replacement for a healthy pregnancy diet.

Women should familiarize themselves with which foods are the best sources of the essential nutrients that are most important during pregnancy. You can do that here.

That said, the recommended daily intake for several vitamins and minerals is elevated for pregnant and lactating women, and even with a well-balanced, nutrient-rich diet, it can still be difficult for some women to ensure that they are meeting optimal levels.

For that reason, prenatal supplementation is recommended, and after writing this guide, I am on board with taking an organic prenatal supplement while trying to conceive and during pregnancy and lactation.

Vitamins While Breastfeeding

There are sometimes significant differences in nutritional guidelines between gestating and lactating women. For non-pregnant women, the RDI of iron, for instance, is 18 milligrams. For pregnant women, that goes up by 50% to 27 milligrams, and for lactating women it goes down by 50% to 9-10 milligrams (depending on age).

These are really significant differences, so it’s worth familiarizing yourself with the recommended daily allowances for all of life’s stages. We love this chart (just scroll all the way down to the bottom of the page).

How to Choose the Best Organic Prenatal Vitamin

Okay, so you know you want to take a prenatal supplement. Now, how do you choose which one?

The first step is to assess your own eating habits to determine specific areas where a supplement might be particularly beneficial.

Next, you’ll want to consider the source material of the vitamin you’re going to buy, as well as the combination of nutrients in your supplement. (This is especially important because of known nutrient interactions that can influence the bio-availability of the ingredients in your prenatal.)

With these issues in mind, the next step is to know whether your prenatal has been tested by a third-party lab to determine whether the items in the ingredient label actually match the contents. Unfortunately, this is not something you can take for granted.

You also should be aware of fillers or other “sneaky stuff” in some supplements that may actually have negative impact on your or your baby’s health.

Lastly, it is important to know which nutrients actually pose toxicity risks if taken in doses that exceed recommended guidelines to avoid possible overdose.

Overwhelmed yet? Yeah, I was, too. This is where Michael stepped in and came up with specific criteria, questions to ask manufacturers, and an organized vetting process for prenatal supplements.

The Best More Affordable Prenatal
Deva

How We Came Up with the List of Best Organic Prenatal Vitamins

This review is mostly going to focus on only the best organic prenatal vitamins because I assume if you’re a reader of mind you aren’t going to want anything that might contain pesticide residue.

This knocks out about half the prenatals on the market right away.

You’ll see a long list of sources at the bottom of this post with links to peer-reviewed primary source data. We also checked recommendation guidelines from the American College of Obstetricians and Gynecologists (ACOG), the Mayo Clinic, and the Institutes of Medicine’s (IOM; aka Federal Guidelines) Recommended Dietary Allowance (RDA) and Tolerable Upper Intake Levels (UL) for safety.

There are some confusing aspects regarding recommendations from these various bodies. This can lead to variations in how the guidelines are interpreted and how much of each nutrient is recommended in a prenatal supplement. Once again, Michael’s scientific background was immensely helpful in making sense of the data and coming up with solid recommendations for you guys.

What to Look for in Organic Prenatal Vitamins

Here’s what we considered when reviewing popular organic prenatal vitamins:

1) Food-Based versus Synthetic Vitamins

Many essential nutrients can been isolated into their pure form in a laboratory. These isolates are commonly used in over-the-counter vitamins and supplements of all varieties.

Of course, food-based nutrients contain co-factors like phytonutrients that help your body absorb or utilize the vitamins, making them nutritionally
superior.

Moreover, there is evidence that certain synthetic vitamins can actually lead to toxicity-related health concerns (synthetic calcium, vitamin E, and beta-carotene, for example).

The only downside to getting food-based nutrients in your supplement is that they tend to be bulkier, and so there is usually a smaller amount of any given nutrient in a food-based versus a synthetic supplement.

Bottom Line: While we aren’t convinced that synthetic nutrients are always inferior to natural, we looked favorably upon those brands using truly food-based nutrients in their formulas.

2) Inclusion of Lesser-Known (But Important) Nutrients

We mentioned seven nutrients that are critical for a healthy pregnancy (you can read more about all of them here), so obviously these are what you want to find in a prenatal vitamin.

Keep in mind, though, that some of these nutrients are really easy to get from food.  Some are better absorbed when combined with other specific nutrients (more on this in a minute). We took all of this into account when reading the labels of some of the most popular organic prenatal vitamins on the market.

Broccoli is rich in choline.

For instance, choline, which supports healthy brain and spinal cord development, is actually very important during pregnancy but not found in many prenatals. (Gestational supplementation of choline has been linked with decreased risk of neural tube closure pathology and improved cognitive function in babies.)

Given the high rates of choline deficiency in the U.S., we gave bonus points to the brands of prenatals that included a food-based version of this nutrient.

Best Prenatal If You Have the MTHFR Gene Mutation

Women who carry this mutation have a harder time absorbing folate, especially in the form of folic acid. If you happen to know that you carry this mutation, look for a supplement containing methylated folate (L-methylfolate).

Ritual Essential Prenatal

3) Vitamin D2 versus D3

D2 (ergocalciferol) is plant-derived and D3 (cholecalciferol) is animal-derived.

Studies have shown that D3 supplementation is more effective at raising vitamin D blood levels. However, our skin produces D3 in the sun, so if you have regular access to sunshine, this is probably not such a big deal.

Bottom Line: If you are not vegetarian, you should try to find a supplement with D3 rather than D2. If you are vegetarian, try to make sure you get some sunshine, and don’t worry about the D2 in your vitamin being harmful.

4) Interactions Between Essential Nutrients

Many different factors influence bioavailability, which refers to how much of a given nutrient is actually absorbed and metabolized by our bodies.

Determining bioavailability is complicated. The source of the nutrient, how it is cooked or prepared, and the other foods or nutrients that are consumed at the same time all influence bioavailability.

We’ve already covered food-based supplements and why they are generally superior to synthetic (basically, co-factors like phytonutrients help you utilize vitamins).

Bottom Line:  It’s impossible to predict the ways that different foods in different combinations will interact to affect the bioavailabilty of one nutrient versus another. This is just another reminder to get nutrients from food as much as you can!

There are a few combos of nutrients that deserve special mention.

Iron versus Calcium

Calcium inhibits the absorption of iron, and both are important essential nutrients for pregnant women. For that reason, many prenatal vitamins contain very little calcium.

The strategy we recommend is to find a prenatal supplement high in iron and try to avoid eating a calcium-rich meal (i.e. high in dairy) when you take the prenatal. Instead, eat calcium-rich foods (or take your calcium pill if you choose to supplement) a few hours apart from when you take your prenatal.

Vitamin C with Iron

The type of iron (non-heme) that you get from supplements and fortified foods should be taken with vitamin C when possible.

Vitamin C helps aid the absorption of non-heme iron, so another way to help combat anemia during gestation is to consume vitamin C rich foods with your prenatal. (You can read a bit more about iron below under “Possible Nutrient Toxicity Risks.”)

Vitamin D with Calcium

Vitamin D is essential for the absorption of calcium. You can help ensure that you’re getting enough calcium by consuming calcium-rich foods with foods high in Vitamin D, such as egg yolks and fortified milk.

If you are vegan or lactose intolerant you may consider taking a calcium supplement during pregnancy, and while there are several different forms/sources of calcium such as calcium carbonate and calcium citrate, it appears that all of these are absorbed equally by the body.

Keep in mind that the amount of calcium your body absorbs is inversely correlated with amount of calcium ingested (above 500 milligram). For instance, it’s better to take two 500 milligrams doses of calcium twice a day that one 1,000 milligram dose.

5) Enteric Coating

Stomach acid can affect bioavailability by breaking down nutrients in supplements before they arrive in the intestines where they can be absorbed.

Supplement tablets can be coated with enteric polymers to increase the bioavailability of nutrients. The coating won’t dissolve at the very low pH
levels found in the stomach, and instead dissolve once the pH becomes more neutral.

Unfortunately, enteric coating can be made from methacrylic acid copolymer, which is absolutely not “Good Stuff,” but it can also be made from a plant-derived cellulose coating derived from algae.

Bottom Line: If you have a sensitive stomach you may want to look for a prenatal with a plant-cellulose enteric coating.

6) Third-Party Testing

You’ll want to make sure that whatever organic prenatal vitamin you choose is third-party tested.

This is not the same as having “seal-of-approval” labels—even if these are from the NIH, or they proclaim that a supplement is “Non-GMO verified.”

True third-party testing means that a laboratory measures the actual contents of the formula against the label claim to see if they match.

For example, with regard to folate, the amount in the pill is often more than the claim on the label. This matters because folic acid has about 70% higher absorption rating than food-based folate or methylfolate. This means that a folic acid content of 800 micrograms is actually the equivalent 1360 micrograms of folate—not to mention whatever you’re getting from your diet.

Unfortunately, third-party testing is only useful if the specific formula ingredient list is still current. For example, we used LabDoor.com at the beginning of this investigation to start compiling and ranking various organic prenatal brands. Then we learned that the last LabDoor report was completed in 2016, and since then, several of the supplements have radically changed their formulations.

To further complicate matters, you really can’t trust a lot of information on websites that have ranked prenatals because often these websites are using outdated or misinformation.

For example, we found that Reviews.com has a lot of misinformation about which prenatals have been third-party tested. After doing some fact-checking, we found that several vitamins that were listed as having not been third-party tested actually were tested. Perhaps this is because the information on Reviews.com was outdated, or perhaps it was just wrong.

Either way, you can’t simply trust what you see posted online in the vast and complicated world of prenatal supplements!

Bottom Line: The best supplement choices will be those that have been third-party tested. Once you decide on a particular brand, you should double check to ensure that the formulation you are buying–and not some previous recipe–was tested.

Best Prenatal for Raw Foodists

Garden Of Life Vitamin Code Raw Prenatal

7) Inclusion of Questionable Ingredients (Sneaky Stuff)

Ideally, you’ll avoid any organic prenatal that contains food colorings, fillers, and additives.

According to LabDoor’s report (2016), four of twenty-two products contained at least one artificial coloring agent (Blue 2, Yellow 6, and/or Red 40).

Other “watchlist” or questionable ingredients identified by LabDoor are: cornstarch, polyethylene glycol, polyvinyl alcohol, sodium benzoate, sodium selenate, sucrose and corn syrup solids, carmine, caramel color, titanium dioxide, butylated hydroxytoluene, and benzoic acid.

One particularly sneaky move involves culturing cheap synthetic vitamins in yeast and then using the yeast culture as if it’s a “food-based” form.

It’s unclear if these yeast cultured vitamins are less effective than truly food-based ones, but either way, it’s not the type of transparency we like to see in our Good Stuff Brands! (Garden of Life does this, but we give them a nod as the only raw organic prenatal vitamin we could find.)

Best Prenatal for Those Keeping Kosher

Megafood Baby and Me 2

8) Possible Nutrient Toxicity Risks

It’s important to know that amount of a given nutrient that your body actually needs will also determine how much is absorbed. Fortunately, for most nutrients, any excess that is not needed by the body will be excreted in the urine.

But there’s a caveat, and to understand it you need to understand the difference between fat-soluble and water-soluble vitamins.

Just as the name implies, water-soluble vitamins dissolve in water, making them more readily available for use in various tissues and also easily excreted when there are excess amounts in the body.

Vitamins in the B-complex and vitamin C are water-soluble. Although it is possible that ingesting these vitamins in excessive amounts for prolonged periods of time can cause some gastrointestinal discomfort, there is very little real risk of “vitamin overdose” (hypervitaminosis).

Fat-soluble vitamins, on the other hand, are dissolved in lipids where they enter through the small intestine and are generally stored for later use.

Because they are stored in tissue, fat-soluble vitamins are not as easily excreted and prolonged excessive intake can lead to hypervitaminosis.

The fat-soluble vitamins include A, D, E, and K, but please note that it is basically impossible to overdose on any of these vitamins from your diet. Only ingesting excess vitamins in the form of supplements can pose any vitamin toxicity risks.

A few nutrients do merit mention when it comes to potential toxicity:

Preformed Vitamin A

Two forms of vitamin A are available in our diet: preformed vitamin A (retinol and retinyl ester) comes from animal sources, and provitamin A carotenoids (beta-carotene being the most important) are plant-derived.

Preformed vitamin A (retinol) can build up in the liver and become toxic at high doses. This condition is called hypervitaminosis A.

The important point here is that the toxic effects of vitamin A are ONLY associated with animal-derived and synthetic retinol, rather than plant- derived or synthetic beta-carotene. So, don’t worry about vitamin A toxicity from beta-carotene, even if it’s synthetic. Do worry about excessive vitamin A intake from animal sources or supplements with synthetic retinol.

Bottom Line: Readers of this website are very unlikely to be vitamin A deficient. Still, supplemental vitamin A in the form of food-derived beta-carotene can provide peace of mind without risking hypervitaminosis A. We looked for organic prenatal supplements that contain vitamin A in the form of food-based beta-carotene.

Synthetic Vitamin E

Naturally-occurring vitamin E consists of eight related compounds, the most important of which is alpha-tocopheryl, usually listed as d-alpha tocopheryl on a supplement label. (The synthetic isolate will begin with “dl” instead of “d.”)

Many websites reference the “problematic” and “potentially toxic” concerns about synthetic vitamin E. After doing some digging, we concluded that the only clear problem with synthetic vitamin E is that it is not absorbed well (less than 50%).

There does not appear to be evidence that excessive vitamin E poses any health risks when obtained through food, but supplemental vitamin E can have toxic effects at very high doses (like increased risk of hemorrhagic stroke and congenital heart defects in newborns).

Unlike other vitamins, this toxicity risk appears to hold true whether the dose is natural or synthetic.

Bottom Line: We looked for prenatal supplements that have the recommended daily allowance of vitamin E and not some crazy high percentage.

Iron

Iron needs double when pregnant, and supplementation is sometimes needed for vegetarian women.

Iron overdose is a significant concern for young children, but you’re more likely struggle with anemia during your pregnancy than with excessive iron intake. We looked for supplements that contained for around 18 milligrams of iron.

Folate/Folic Acid

Avocados are a good source of folate.

In view of evidence linking folate intake with neural tube defects in the fetus, it is recommended that all women capable of becoming pregnant consume folate from supplements or fortified foods in addition to intake of food folate from a varied diet.

Despite several websites warning about the risks of excessive folate intake, according to the NIH factsheet, there is no upper limit for food-derived folate.

The upper limit of folic acid, which is synthetic folate, is 1,000 micrograms per day. (See the section on Third-Party Testing for more on the differences in bioavailability of folic acid versus folate).

Note that there IS a risk of excess folate masking a B12 deficiency. This can happen because the folate supplement will prevent the symptoms of anemia that are associated with deficiency of either B12 or folate; it will not prevent the progression of neurological damage that accompanies B12 deficiency.

Bottom Line: The best prenatal supplement will have food-derived folate, rather than folic acid. If a supplement does contain folic acid, there is no reason for it to ever be higher than 600 micrograms.

9) Omega Fatty Acids

Pregnant women should aim for two servings of seafood per week.

You’ve probably heard a lot of buzz around how crucial omega-3s are for the optimal development of a fetus.

While omega-6 fatty acids are abundant and readily available, omega-3 fatty acids make up a much lower proportion of the modern American diet.

Because omega-3 and -6 fatty acids are essential nutrients (cannot be synthesized by the body),  they must be consumed in the diet. This means they are transferred via the placenta from the mother to fetus.

There is a general consensus among medical professionals that pregnant women in the United States and Canada do not get enough omega-3 fatty acid, specifically DHA; both the Environmental Protection Agency and The ACOG recommend that pregnant women consume twelve ounces (340 grams) of seafood per week from low-mercury species.

The recommended two servings of marine food per week will provide an average intake per day of 100 to 250 milligrams total of omega-3 fatty acids. Of that, 50 to 100 milligrams will be of DHA. For women following this recommendation, the remaining 200 to 250 milligrams of recommended DHA will have to come in supplement form.

Frustratingly, it looks like the benefits of omega-3/DHA supplementation during pregnancy is really not that well supported. Yes, several studies have linked adequate intake of fish during pregnancy with a variety of benefits, but well-controlled, randomized trials looking at omega-3 supplementation (as opposed to just eating fish), have been largely disappointing. UPDATE: This brand new study suggests that omega-3 supplementation during pregnancy significantly reduces the risk of premature birth.

Bottom Line: We feel that in addition to eating low-mercury fish when pregnant, it makes sense to take a fish oil supplement.

Ranking the Organic Prenatal Vitamins

Once we decided what we wanted to find in prenatals, the next step was looking at the options available and categorizing them into Best, Good, Bad, or Sneaky Stuff.

In terms of which is the best vitamin for YOU, some of that depends on your lifestyle and circumstances—you’ll see that, for example, a few of them are vegan, one of them is raw, and one is significantly less expensive than the others.

All of them except Deva are some version of food-based, or at least isolated/synthetic vitamins mixed with an herbal or fruit/veggie blend to add in the phytochemicals and coenzymes, etc.

Naturelo and Ritual are special because they are vegan but use the good form of vitamin D (D3), which they get from lichen. (All the others get D3 from lanolin (derived from sheep’s wool) or some other animal source, or they use D2, which is veggie-derived but not as well absorbed by the body.)

The Best Stuff

The Good Stuff

The Okay Stuff

The Bad Stuff

The Sneaky Stuff

Seeking Health Prenatal

A lot of you asked about this brand, but it doesn’t not contain iron, contains a potentially dangerous form of vitamin A (retintyl palmitate), and the dosages grossly exceed RDA for almost everything.

It’s also super expensive ($120 for two months) and it requires swallowing eight pills a day which seems burdensome, especially since most women will also need an iron supplement.

It’s not food-based, and it uses the cheap chelated synthetic vitamins,

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Zahler

While these prenatals are kosher, contain D3, and use methylated folate, they aren’t food-based. A bigger issue is that Zahler uses retintyl palmitate for vitamin E. They are also not third-party tested.

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Thorne

While this brand is highly ranked by several bloggers, it’s not food-based and appears to use chelated metals for most of its minerals. We tried calling them twice without being to reach anyone.

.

P.S. I debated posting this, but here’s a little note that Mike wrote to me after he had finished two months of research on this. Do with it what you will! (He definitely didn’t intend for this to be shared with all of you, but we are nothing if not transparent here at Gimme!)

“Maia, I have to say that from my PERSONAL perspective, while I don’t disagree with the basic premise that supplements can help to optimize nutrients during gestational development, I strongly feel that YOUR READERS generally have the means available to eat a well-balanced, nutrient-rich diet. Unless they have a particular medical condition that will put them at higher risk for a deficiency during pregnancy, there is absolutely no reason that YOUR READERS can’t go to the beautiful chart provided via HealthBeat and see which foods are good sources for each of the essential nutrients in question and then make a point to eat those foods, as well as perhaps very specific (i.e. one or two nutrients) supplementation for vegans/vegetarians.”

P.P.S. Here’s the most recent pic I have of Michael and me, from Nantucket this summer.

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