Last updated: October 27, 2020

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Discussions about folic acid are often linked to pregnancy and lactation. This supplement is routinely used as the “prenatal vitamin”, but do you know why? In this article, we will answer all your questions about this nutrient: how it was discovered, its functions and why it is so popular with pregnant women.

Folic acid contributes to cellular development and DNA replication – which is why it is so important during the fetal developmental stage. However, this supplement can also be an interesting addition to anyone’s diet, pregnant or not. Do you want to know more? Keep reading!

Key Facts

  • Folic acid is the synthetic form of vitamin B9 (folate).
  • Natural folate is abundant in vegetable-based food, especially in legumes and green leaf vegetables.
  • Vitamin B9 is a crucial element in the process of cell division and in the replication of DNA. A vitamin B9 deficiency will cause abnormalities in the fetus and anemia, and neurological disorders in adults.

Our Selection: The Best Folic Acid Supplements Available on the U.S. Market

This ranking guide will help you to choose from the best supplements available on Amazon right now. After hours of research, we have chosen the five products that stand above the rest. If you want a folic acid supplement of top quality and at an economic price, look no further and take a close look at the following products:

The Best Vegan Folic Acid Supplement

Here we have a fantastic product from 365 Everyday Value. Brought to you by Whole Foods Market, this product is great value for money and is free of artificial colors, artificial flavors, or artificial preservatives. It is a powerful supplement containing 800 mcg of folic acid and is a vegan friendly way to support healthy prenatal development.

Nothing but positive reviews of this product from users. It is easy and convenient to take, great value for money and is not reported to cause nausea or stomach upsets like some other supplements on the market. You can’t go wrong with this great quality product!

The Most Potent Folic Acid Supplement

GNC Folic Acid 1000 MCG Dietary Supplement provides important prenatal support. An essential vitamin in the B-complex group, folic acid supports healthy fetal development. Each vegetarian tablet provides a huge 1000 micrograms of folic acid – making it the most potent supplement on our list. It is slightly more expensive than the offering from 365 Everyday Value, but still great value for money.

Happy buyers of this product report great results with this supplement. It comes in a soft gel capsule, which makes it nice and easy to take. Although, it is slightly more expensive, it is great for people who have been prescribed a higher daily dose of folic acid by their health professional.

The Best Tasting Folic Acid Supplement

Here is another great option, this time from Nature’s Bounty. This company has a long, established history of making quality supplements and health products. Whatever your reason for taking a folic acid supplement, you won’t regret purchasing this great product and adding it to your dietary regime.

Fantastic reviews of this product from happy buyers. Many people who regularly take this type of supplement, have found this particular product to have a more pleasant taste than other similar supplements from other manufacturers. Some users have reported improved growth of hair, nails and even eyelashes.

The Best Value for Money Folic Acid Supplement

Here we have a product from Amazon’s own brand. It is not the cheapest product on our list to purchase, however considering it provides an 8 month supply – it definitely offers the best value for money. With 400 mcg folic acid per serving (1 tablet), this product is perfect for people who don’t want to take an high daily dose of folic acid.

Buyers are very happy with this product from Amazon, especially because of the great value it offers. The tablets have a pleasant taste and buyers love that they can trust the quality of the product, as Amazon have put their name on it.

The Best 5-MTHF supplement

Looking for a 5-MTHF supplement instead of one made from folic acid? This is definitely the best option on the market in terms of price and quality. Every Thorne product is made with the purest possible ingredients – without gluten or other major allergens (eggs, tree nuts, peanuts). This product also contains no soy, dairy, yeast, fish, or shellfish.

It’s hard to find any negative comments about this great product at all. This is definitely considered the best product of this type on the market. Users report feeling more energetic, happier and sleeping better soon after beginning to take this supplement.

Buyer’s Guide: Everything You Should Know About Folic Acid Supplements

Folic acid (vitamin B9) is vital for pregnant women and their unborn child in the prevention of fetal anomalies. The rest of the general population can also benefit from the consumption of folic acid or folate. This nutrient brings more energy, preventing anemia and acts to protect against cardiovascular disease.

Folic acid is essential for the protection of cells.
(Source: Subotina: 25227239/

What is folic acid exactly?

In 1931 the famous hematologist Lucy Wills discovered that it is possible to treat anemia in pregnant women with beer yeast, which is rich in folate. Years later, the first artificial folate supplements were synthesized (from spinach extract) in the form of folic acid.

Folate is an indispensable nutrient for life, which regulates DNA replication and the formation of new cells. This substance is also known as vitamin B9. The term folate comes from the Latin word folium (meaning leaf), indicating the primary source of this nutrient.

Foods rich in folic acid have many health benefits.
(Source: Mapkenova: 77402770/

Remember that complex B vitamins are hydrosoluble. This means that they are found dissolved in water that is present in different types of food. Ingesting too much of these vitamins is easily compensated thanks to renal elimination (urine). Therefore, cases of toxicity from excessive amounts of vitamin B9 in the system are very infrequent.

What are the differences between folate and folic acid?

Vitamin B9 exists in its natural form (folate) or as an artificial product (folic acid). It is possible to observe tiny differences in the molecular structure of these two versions of vitamin B9. Folic acid is metabolized, absorbed and used by the body in a substantially different manner than the food-based version of the same vitamin known as folate.

Part of the folate found in food is directly converted into the active form of vitamin B9 during digestion. Conversely, the activation of folic acid is slower and requires action from the liver. Therefore, synthetic vitamin B9 can accumulate in the blood stream, waiting to eventually be metabolized.

Broccoli, avocado, papaya, peanuts, salmon… and the list continues. You don’t have any excuse for not having enough folic acid in your food.
(Source: Ekatepnha Mapkenoba: 77993448/

Recent studies have found a link between high levels of synthetic folic acid and the onset of certain illnesses. Therefore, some people prefer to get their vitamin B9 from natural sources. In the following table, you can check out the main differences between folate and folic acid:

Folate Folic acid
Source Natural (present in foods) Artificial (supplements and fortified foods)
Activation Intestinal and hepatic Hepatic
Bioaccumulation (What happens to the excess?) No excessive or toxic accumulation The excess accumulates in the blood. It can be toxic
Toxicity Toxicity has not been associated with high levels May mask the symptoms of B12 deficit. High concentrations that are not metabolized can be toxic
(absorption capacity of the body)
Variable (approximately 50%) Very high: 100% (supplements) and 85% (fortified foods)
Recommendations Recommended to be taken daily Recommended for supplementation during pregnancy and breastfeeding

What is the purpose of folate?

Vitamina B9, or folate, acts in conjunction with vitamin B12. They contribute to the process of DNA replication and cellar synthesis, promoting the creation of new blood cells and the rejuvenation of body tissue. This process is vital for the growth and development of children.

On the other hand, it has been proven that folate contributes to a reduction of levels of homocysteine in blood. Homocysteine is an amino acid that has been linked to cardiovascular disease in high quantities. Folate permits the transformation of excessive homocysteine into methionine, another amino acid that is less dangerous.

What is the recommended daily intake (RDI) of folate?

It is important to take an adequate amount of folate each day to keep the levels of this vitamin within a healthy limit. In the following table we show you the recommended daily intake (RDI) of vitamin B9 depending on age, gender and other factors such as pregnancy:

Demographic Dose (micrograms/day)
Babies 0-6 months 65
Babies 7-12 months 80
Children 1-3 years 150
Children 4-8 years 200
Children 9-13 years 300
Males over 14 years 400
Females over 14 years 400
Women who are pregnant or planning pregnancy 600-800
Women who are breastfeeding 500

To ensure proper fetal development, experts recommend an increased dose for pregnant women. This increased recommended daily dose of B9 can be achieved with a diet that is abundant in foods rich in folate. Although it is generally better to use either a supplement or fortified foods containing folic acid.

How does a folate deficit occur?

A vitamin B9 deficiency can occur if the intake of folate is inadequate (due to prolonged fasting or improper diet), with issues of malabsorption (related to Chron’s disease), if the the body is using more folate than normal (during pregnancy or breastfeeding) or if there is a lack of this vitamin in the body (after the use of certain medications).

There is another hypothesis that links the lack of folate with the excessive use of solariums. It has been shown that ultraviolet light degrades vitamin B9, making it inactive. This is why it is suspected that the overuse of UV light surface devices on the skin, could also reduce folate levels in the blood.

A study in 2014 by the University of Queensland (Australia) saw a reduced effectiveness of folic acid in young women exposed to UV radiation from the sun, directly after taking a supplement.

What issues arise from a folate deficiency?

A chronic folate deficiency is rare in today’s world, especially if we keep in mind that the majority of processed foods (such as cereals, cookies and pastries) are fortified with folic acid. Even so, this deficiency does appear in certain population groups, causing the following issues and symptoms:

  • Neural tube defects of the fetus: A folic acid deficiency has been linked to an increase in fetal abnormalities such as spina bifida (abnormalities in the formation of the spinal cord) and anencephaly (absence of part of the brain or skull).
  • Skin and hair disorders: Folate deficiency can be accompanied with dry and peeling skin. It can also cause changes in hair color, generally resulting in the early onset of grey hair.
  • Anemia: Anemia is defined as a decrease in the normal number of red blood cells, which adversely affects the transport of oxygen and nutrients to body tissue. This type of anemia is called megaloblastic (enlarged red blood cells) and is often confused with pernicious anemia – caused by a vitamin B12 deficiency.
  • Neurological and psychiatric affects: If anemia remains unchecked over a long period of time, issues such as insomnia (at night), drowsiness (during the day) memory loss, changes in sensitivity and equilibrium, depression and even dementia can occur.

The onset of anemia is slow and neuropsychiatric changes can go unnoticed in adults. A healthy person has a reserve of folate in their body. If you are suffering from a deficiency (for example, due to malnutrition or disease), the effects of folate deprivation will take about four months to manifest.

Another type of B9 deficiency is an acute deficiency. In this case, there is a loss of folate due to the use of certain pharmacies, such as methotrexate (an antitumoral agent), causing dermatitis, diarrhea and mouth and tongue ulcers. This type of medication is accompanied by a supplement that prevents the occurrence of the majority of complications.

If you want to adjust your dose of a supplement with precision, it is a great idea to buy a product in powder form.
(Source: dolgachov: 54776175/

What foods are rich in folate?

Vegetable-based foods, such as green leaf vegetables and legumes are rich in folate. It is also possible to find this vitamin in animal-based foods, such as veal livers or blue fish.

In the following table, you can check out information about the main sources of folate:

Food Dose of folate (mcg) per serving % of the recommend daily intake
Lentils 358 90
Chickpeas 282 71
Spinach 263 65
Asparagus 262 65
Veal livers 212 52
Chard 177 44
Papaya 115 29
Avocado 110 28
Peanuts 88 22
Broccoli 84 21
Oranges 40 10
Salmon 14 4

It is important to note that the cooking process will eliminate some of the folate present in these foods, and decrease their nutritional value. If you really want to get the most out of your diet and increase your vitamin B9 intake, increase the amount of raw fruit and greens you are consuming. Steaming and the use of microwaves will also limit the amount of folate eliminated, compared to other cooking methods.

Unfortunately, these tips are not suitable for pregnant women. Generally speaking, it is recommended that pregnant women should consume foods that are very well cooked, to avoid any type of infection (such as food poisoning) that could be harmful to the fetus. This is why the use of a folic acid supplement is a much safer and beneficial option for pregnant women.

Who can benefit from a folic acid supplement?

It is possible that in certain groups of people, the ingestion of folate from the diet alone will not be sufficient to ensure adequate levels of B9. If this is the case, the addition of a folic acid supplement to your daily regime will prevent the onset of a deficiency.

The following groups of people can benefit from the use of a folic acid supplement:

  • Pregnant or breastfeeding women: Pregnancy produces an increase amount of vitamin B9 required by the body. The use of a folic acid supplement will ensure that the recommended daily intake is maintained.
  • People over the age of 65: A folate deficiency in older people can manifest as memory loss and impaired vision. The use of a supplement can keep these issues at bay.
  • Newborn babies (especially premature babies): If the levels of folate of the mother were insufficient, a newborn baby can require extra folic acid to avoid anomalies in growth and development.
  • People with intestinal malabsorption: Some illnesses (such as Chron’s disease, celiac disease and ulcerative colitis) reduce the proper absorption of nutrients (like folate) via the intestinal system. The use of a supplement can help to avoid a vitamin B9 deficiency in people with intestinal malabsorption.
  • People with an alcohol problem: Although the moderate consumption of beer has been shown to increase levels of folate, overindulging in liquor with a high alcohol content (such as whiskey or gin) can have the opposite effect. In this case, adding a daily supplement to your diet is a good idea.
  • Consumption of certain pharmaceutical drugs: Some pharmaceutical drugs (antitumors, antiepileptics, antimalarials, anti-rheumatics, oral contraceptives, diuretics and some antibiotics) that have an antifolate action, reducing the reserves of B9 in the body. If you are taking one of these drugs, it is highly recommended that you combine it with a supplement to avoid a folic acid deficiency.
  • People with a metabolic disorder: Genetic alterations have been reported in people with a partially or totally reduced capacity to absorb, activate or retain folate. For these people the ingestion of folic acid (or at least active forms of vitamin B9) is vital to avoid a resulting deficiency.
  • People with cardiovascular disease: Adequate levels of B9 help to reduce the amount of homocysteine circulating in the blood. This reduces the probability of the occurrence of cardiac arrest. The use of a folic acid supplement will help to keep the amount of vitamin B9 in your body at an adequate level.
  • People with vitiligo and psoriasis: An increased intake of folic acid has been shown, in the majority of clinical studies, to improve the symptoms of these skin diseases.

There are other claims often made about the benefits of folic acid. For example, this nutrient is often recommended to anyone looking to improve the texture and growth of their hair. However, clinical studies have not been able to verify the effectiveness of folic acid for improving hair growth, with little or no benefits being observed.

The role that folic acid can play in the treatment of depression is also currently being investigated. The consumption of folic acid produced positive effects in 20% of patients simultaneously being treated with vitamin B9 and antidepressants. Unfortunately, this research is still in its infancy and more data is needed to prove this popular hypothesis.

Folic acid can be found in a wide-range of different foods.
(Source: ratmaner: 105448070/

Why is folic acid important during pregnancy?

Every year in the USA, 3,000 births are affected by defects of the neural tube (the embryonic precursor to the central nervous system). Although the exact cause of this type of malformation is unknown, it has been shown to appear more frequently in the children of mothers with inadequate levels of folate.

The introduction of folic acid as a recommended supplement taken during pregnancy, has been calculated to reduced the appearance of neural tube defects by a range of 50-70%. These claims come from reliable and recognized studies, such as the clinical trial conducted by the United Kingdom Medical Research Council.

It is important to be aware of the issues that arise from a lack of folic acid – including anemia.
(Source: Jarun Ontakrai: 98685168/

These days it is recommended that women who are planning on conceiving, should take a supplement of 0.4 mcg (400 micrograms) per day. Ideally, they should begin one month before conception and continue taking the supplement during the first 12 weeks of the pregnancy. Some women may require a higher dose, for example women who are taking antiepileptic drugs.

What type of folic acid supplements are available?

Folic acid is the most popular synthetic form of vitamin B9 when it comes to supplementation. However, there are people who are unable to metabolize the vitamin in this form. This causes the folic acid to accumulate in the bloodstream and increases the risk of serious diseases (such as cardiovascular disease and cancer).

These people can increase their intake of folate by consuming supplements of levomefolic acid (5-MTHF). This substance is vitamin B9 in its active form, it is capable of supplying all the benefits of folate without needing to be metabolized.

In the following table we compare these two types of supplements:

Folic acid supplements 5-MTHF supplements
Molecular structure Artificial Identical to the natural form
Bioavailability Very high (100-85%). Inadequate gastric pH level can prevent proper absorption Very high (100-85%). Independent of gastric pH level
Activation Liver metabolism It is not necessary
Toxicity It can mask the symptoms of a B12 deficiency. High concentrations that are not metabolized can be toxic Does not mask the symptoms of a B12 deficiency. Does not accumulate when in an inactive state
Side effects Very few (hypersensitivity reactions) Have been reported: Irritability, insomnia, muscular pain, joint pain, acne, skin irritation, anxiety, palpitations, headaches, migraines
Safety Very safe at the recommended dose Probably safe. Being studied
Price Affordable (6-15€) Higher (20-40€)

Folic acid supplements are a cheap and safe option for most people. However, people with metabolic issues should use a levomefolic acid (5-MTHF) supplement to increase their levels of vitamin B9. If you experience any side effects after use, immediately stop taking the supplement and consult a medical professional.

How much do folic acid supplements cost?

Folic acid supplements are very affordable, usually costing anywhere between $5-$20. Pregnant women can get these supplements even more cheaply with a medical prescription. The biggest factors that influence the final price of a product are the brand, a stronger than normal dose and the inclusion of additional compounds.

On the other hand, supplements containing levomefolic acid are much more difficult to find. 5-MTHF can also be obtained with a medical prescription, however it has much stricter guidelines for use. It is useful for people with a metabolic deficiency, who are unable to gain any benefit from folic acid. As an over-the-counter supplement, it is more expensive at around $20-45.

Joe LeechNutritionist. University of Wollongong, Australia
“[Taking a levomefolic supplement] Think of it like receiving a cooked meal instead of all the raw ingredients. An MTHFR mutation is equal to not having the pots and pans to cook with.”

How do I take a folic acid supplement?

Taking a folic acid supplement is very easy. All you need to do is take a tablet that contains the daily recommended dose (between 250 and 400 mcg) once per day – preferably before breakfast. Some people can suffer from an upset stomach after taking these supplements, in this case it is recommended to take it with food.

Supplementation with folic acid or 5-MTHF should be intended to be undertaken over a limited period – around four months. Women who are of a reproductive age are an exception to this rule, with some guides recommending a small daily dose of B9. This will ensure the health of a future embryo in the case of an unexpected pregnancy.

Vitiligo is an illness that causes changes in the pigment of the skin. A folic acid supplement can help to mitigate the symptoms of this disease.
(Source: Andrii Afanasiev: 75815057/

What side effects can be caused by taking a folic acid supplement?

Supplementation with folic acid is considered safe. Minor side effects have been reported, such as nausea, stomach cramps and general malaise by some people after taking tablets of this type. Anyone experiencing these types of side effects should make sure they take the tablets with food, or just before going to bed.

It is important to note that some studies have found an increase in the incidence of cancer and cardiovascular disease in people taking very high doses of folic acid (above 1000 mcg) over a long period of time. This is why experts recommend never exceeding the recommend maximum dose of 1mg.

Finally, adverse side effects have been reported with the consumption of 5-MTHF, like irritability, insomnia, body aches and pains, skin irritation, anxiety and headaches among others. However, these side effects do not affect all individuals and there are no indicators that allow us to predict if someone is or is not susceptible to presenting with these symptoms.

In most cases, any nausea resulting from taking a folic acid supplement will subside within a few weeks.

What contraindications do folic acid supplement have?

Folic acid supplements are contraindicated for people with hypersensitivity to this compound. Similarly, this product is not recommended for people with defective folate metabolism (alterations in the MTHFR gene). A levomefolic supplement is recommended for these people.

Another important contraindication to look out for when using this type of product, is the presence of a concomitant vitamin B12 deficiency. If this is the case, the use of folic acid can mask the early symptoms of a deficiency of this vitamin, making treatment more difficult and increasing the risk of more serious complications.

Steven MageeAmerican Health Expert and Researcher
“There is a very strange and undetectable sickness in the modern population that responds to huge doses of vitamin B12.”

Shopping Criteria

Choosing a vitamin B9 supplement can be a complicated process. Are you trying to decide between a folic acid or 5-MTHF supplement? Are you unsure if you should opt for a supplement that combines iodine and iron in addition to vitamin B9? Don’t stress out! Just follow our shopping criteria, which will help you to choose the product that best suits your need:

Drug Interactions

Folic acid has very few drug interactions. Usually a combination of a certain drug with vitamin B9 will make the supplement less effective. If you are taking any of the following medications, we recommend discussing whether folic acid is the right supplement for you with your doctor:

  • Anticonvulsants (medication for the treatment of epilepsy)
  • Methotrexate
  • Drugs for the treatment of malaria

Vitamin B9 tablets are an easy way to supplement your diet.
(Source: Siamphotos: 103700457/

Contains 5-MTHF

Depending on your individual situation (prescription antiepileptic drugs, genetic alterations or malabsorption disorder), it might be good idea to change your folic acid supplement for a 5-MTHF supplement instead. The active form of Vitamin B9 offers all the benefits of folic acid, without needing to be metabolized beforehand.

Vegan and Vegetarian Friendly

Luckily, folic acid supplements are available in forms that are suitable for vegans and vegetarians. If you want to use a product that is free of animal-based products, be careful to ensure that the covering gel of the capsule is made from vegetable-based materials. Or just simply look for the vegan quality seal on the packaging of the product you are thinking about purchasing.

Folic acid supplements suitable for vegans and vegetarians have a characteristic seal that makes them easy to recognize.
(Source: themoderncanvas: 57067475/

In the following table you can see the recommended dose (according to the leading experts) for each population group. However, remember that the optimum dose of folic acid will vary from person to person and should be adjusted for each individual – preferably after a consultation with a health professional.

Population group Recommended dose
People with a folate deficiency 250 mcg – 1000 mcg
Pregnant women, prevention of neural tube defects in the fetus 400 mcg
Breastfeeding women 250 mcg – 400 mcg
People with elevated homocysteine levels 200 mcg – 15000 mcg*
People with symptoms of depression 250 mcg – 500 mcg
Muscular degeneration due to aging 2500 mcg*
People with vitiligo 5000 mcg*

*Taking high doses of folic acid requires supervision by a healthcare professional.

Method of Consumption

Typically, folic acid supplements come in the form of capsules, tablets or pills that must be swallowed with water at the same time every day. It is also possible to buy folic acid and 5-MTHF in powder form. This form is much more popular among bodybuilders, than it is with the wider public.

Folic acid is recommended for pregnant women and can be found in “prenatal vitamins” products. These usually contain (in addition to vitamin B9) compounds such as iron, B12 and iodine. If you are pregnant or are planning to conceive, you should talk with your doctor or midwife about what type of supplement would be most suitable for you.

Dr Payam RezaieNeuroscientist and Leading Specialist on Autism
“Maintaining an adequate intake of essential nutrients, including folic acid and vitamin B12, is crucial during pregnancy to avoid serious birth defects and harm to the unborn child. Expert medical advice should always be sought when planning for pregnancy, and followed up during the course of pregnancy and after birth, to prioritize the health of both mother and child.”

Value for Money

Without a doubt, folic acid supplements are much more economical than those made with 5-MTHF. It might be a cheaper option if you purchase a large container, with a sufficient quantity of supplements to last for three to four months. Vitamin B9 powder might be more expensive, but it will allow you to perfectly measure the dose you are taking.


Folic acid has been a revolution for the health of pregnant women and newborn babies. As a prenatal supplement, it reduces the occurrence of anomalies of the neural tube, ensuring the birth of healthy and strong babies. It is important to remember that this supplement also has many health benefits for the wider population as well.

We hope this article has been informative and you have learned more about this nutrient. Keep in mind that (when it is used correctly) folic acid is an extremely safe and useful supplement. Combined with a healthy diet and an active lifestyle, you will be sure to get the maximum possible benefit from this nutrient.

Did you enjoy this article about folic acid? If so, be sure to leave a comment and share it on social media!

(Source of featured image: Yemelyanov: 47531853/

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