Last updated: 17/10/2022

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Welcome to our Folic Acid Review! Today we are going to talk about an important vitamin for your health: folic acid.

Part of the B complex, folic acid, also known as vitamin B9, is essential for several functions in the body, besides being essential during pregnancy.

In this article we’ll show you what you should consider before buying the right folic acid.


  • Folic acid is an essential nutrient for the good functioning of the organism since it protects the heart, prevents neuropsychological diseases and acts in the formation of the neural tube of the foetus, among others.
  • Folic acid supplementation must always be taken under medical supervision in cases of deficiency, anaemia and during pregnancy.
  • We will show you which characteristics differentiate one folic acid supplement from another and how to choose the best one.

The best Folic Acid: Our Picks

Buying Guide

It may seem simple to choose the best folic acid. But the fact is that this is a supplement that, despite its benefits, should be taken with caution and preferably with the guidance of a doctor.

That is why we have created this Buying Guide with all the information you need to make the best decision when buying your folic acid supplement.

Mulher grávida segurando comprimidos e copo de água.

Folic acid is essential for a good pregnancy and overall health. (Source: Anna Bizoń / 123RF)

What is folic acid?

Folic acid is a vitamin that is part of the B complex and is therefore essential for the health of your body. Also known as folate and vitamin B9, folic acid is actually the synthetic form of folate.

Water soluble, folate is found naturally in food. Its synthetic form, folic acid, is used in the manufacture of medicines, foods and supplements.

Folic acid is used by our bodies to create blood cells, help heal wounds, build muscle and produce essential substances for the brain and nervous system.

Cápsulas em um frasco de vitamina.

Folic acid can be consumed in the form of supplements or through the diet. (Source: frolicsomepl / Pixabay)

The fact is that folic acid is a key vitamin for DNA formation and is especially important in foetal development.

Because of its importance in the proper functioning of the body, especially, but not exclusively, for pregnant women, folic acid needs to be replenished daily.

This demand occurs because our body cannot store the vitamin for long. Because it is water-soluble, folic acid is even released through the urine.

Why is folic acid important during pregnancy?

Folic acid is an especially important nutrient for pregnant women. This is because it plays a role in the correct development of the foetus and the formation of the neural tube.

Due to its importance in the formation of babies, experts recommend that those who intend to become pregnant or who are in the beginning of their pregnancy should, together with their doctor, consider supplementation.

Folic acid supplementation should preferably be started at least one month before pregnancy. In addition, vitamin B9 supplementation should be maintained for the first eight weeks after conception.

It is precisely during this period that the development of the nervous system and neural tube of the foetus occurs, which will give rise to the brain and spinal cord.

Folic acid, therefore, acts to prevent and reduce the chances of the baby being born with any malformation.

Mulher grávida ao ar livre.

Folic acid prevents cognitive malformation in the baby. (Source: Pexels / Pixabay)

A study by the University of California, in the United States, found that the use of folic acid supplementation in pregnancy decreases the chances of the baby being born with autism, for example.

Even though, nowadays, most are unplanned pregnancies, experts warn about the importance of planning.

According to researchers, pregnancy planning is the best way to prevent neurological malformations, since you can take the correct dose of folic acid beforehand.

According to the Brazilian Federation of Gynecology and Obstetrics Associations, with folic acid supplementation before and during the first trimester of pregnancy, it will be possible to reduce the risk of malformation of the foetus by 85%.

What is folic acid used for?

In addition to its importance for the correct formation of the baby’s nervous system, folic acid is necessary for several other functions in our body.

These include DNA synthesis and repair, cell division and growth, the production of new proteins and the formation of red blood cells.

Vitamin B9 is also important for cardiovascular and nervous system health, but its benefits go even further. Check them out below:

Ally of skin, nails and hair

All B-complex vitamins, including folic acid, are active in the health of the skin, nails and hair.

Specifically, vitamin B9 helps in the growth of nails and hair, fights acne and dermatitis and controls skin oiliness. In addition, folic acid protects against cancer and helps control the evolution of vitiligo.

Mulher com cabelo e rosto saudáveis.

Vitamin B9 strengthens hair and nails, in addition to fighting acne and dermatitis. (Source: Pixabay / Pexels)

Strengthens immunity

Folic acid, along with other B vitamins, also plays an important role in strengthening the immune system and preventing infections.

Good for the brain

Folic acid plays an important role in maintaining brain functions, cognitive ability and mental health. In fact, adequate levels of vitamin B9 in the body can even prevent episodes of depression.

According to studies conducted by the Institute for Functional Medicine in Florida, United States, more than 40% of cases of depression are caused by a lack of vitamin B9 in the body.

This is because folic acid acts in the production of serotonin, a neurotransmitter that ensures a good mood.

Mulher pálida e triste.

Folic acid supplements also combat depression, anaemia and protect the heart. (Source: Engin Akyurt / Pexels)

Protects the heart and circulatory system

Folic acid helps prevent heart attacks and other heart diseases. When it combines with B6 and B12, forming a coenzyme, a decrease in the rate of homocysteine occurs.

Homocysteine is an amino acid that, besides being the greatest factor in heart attacks, also harms the circulatory system. There are even some studies that state that vitamin B9 protects against strokes.

Combating anaemia

Folic acid is also responsible for acting to stimulate the production of blood cells and to improve the absorption of iron by the body.

Prevents cancer

Folic acid supplementation can also prevent the development of cancer. According to experts, vitamin B9 also helps prevent changes in DNA.

With this, the nutrient prevents the formation of defective cells and, consequently, prevents the appearance of some types of cancer. The American Cancer Society has even declared that folic acid prevents the progression of the disease.

What is the recommended amount of folic acid?

According to the United States National Academy Institute of Medicine, the optimal amount of folic acid that should be consumed every day varies according to age.

But this amount can also vary according to the degree of deficiency and nutritional needs of each person.

But to give you an overview of the dosage variation for each age group check the table below:

Age group Amount of vitamin B9 recommended daily (mcg)
0 to 6 months 65
7 to 12 months 80
1 to 3 years 150
4 to 8 years 200
9 to 13 years 300
Over 14 years 400
Pregnant women 400 to 600
Lactating women 400 to 500

What are the foods rich in folic acid?

As we have seen, folate, in its natural form, is found in many foods that we use in our diet. Foods rich in folate are usually dark leafy greens such as spinach, broccoli, cabbage, lettuce and parsley.

But pulses, fruit, vegetables, eggs and even some meats also contain good amounts of vitamin B9.

The table below shows some of the foods richest in folic acid and the amount in 100 gram portions.

Food (100g) Folic acid (mcg)
Chicken liver 770
Beef liver 220
Chickpeas 340
Beans 210
Green cabbage 185
Lentils 179
Cornflakes 167
Spinach 150
Parsley 150
Asparagus 150
Soybeans 100
Beef kidney 98
Cabbage 98
Broccoli 90
Avocado 62
Orange 31
Wholemeal bread 31
Salmon 24

In addition to these foods, there are also some products that are fortified with folic acid, such as wheat flour. Therefore, products such as bread, biscuits and pasta can also be sources of vitamin B9.

However, you need to pay attention to the preparation of these foods. According to experts, depending on the way the food is cooked, losses of the vitamin may occur.

The most recommended is that you cook with as little water as possible and with the pot covered.

What are the symptoms of folic acid deficiency?

You need to keep a close eye on your body’s folic acid levels. This should be done through laboratory tests and monitoring by your doctor.

Monitoring your rates is crucial because most of the time folic acid deficiency does not cause any physical symptoms.

However, in more severe cases of folic acid deficiency, health problems can occur, such as fatigue, shortness of breath after mild exertion and mouth sores.

Homem com as mãos na cabeça.

In addition to causing vitamin B12 deficiency, excess folic acid can cause nausea and headaches. (Source: Nathan Cowley / Pexels)

In addition, an intense deficiency of folic acid can even lead to anaemia. And as we saw in the case of pregnant women, the absence of this vitamin can cause the fetus to have neurological malformation.

But there are also other symptoms that can arise as a result of low levels of folic acid in your body. They are

  • Canker sores
  • Tiredness
  • Diarrhoea
  • Headache
  • Shortness of breath
  • Malaise
  • Paleness

If you experience one or more of these symptoms, see your doctor to review the best way to raise your folic acid levels, either through diet or supplementation.

When and how to take folic acid?

As we have seen, it is important that you have regular blood tests and consult your doctor to determine if and how much folic acid you need to supplement.

But in general, vitamin B9 is recommended as a supplement for pregnant and lactating women, as well as for people with anaemia, excessive homocysteine, among others.

Mulher segurando comprimido e copo de água.

Pregnant women, people with anaemia and people with excess homocysteine should supplement folic acid. (Source: / Pexels)

As folic acid is absorbed in the upper half of the small intestine, experts recommend that you should take the tablet about 30 minutes before meals.

This way, you help the absorption of the nutrient by preventing it from mixing with food during the digestive process.

In addition, experts suggest that you, whenever possible, try to combine folic acid with other or even all B vitamins. By doing so, you reduce the chance of causing an imbalance between the vitamins.

What are the problems caused by interactions of folic acid with other substances?

Although it is beneficial to combine folic acid with other vitamins and nutrients, some substances and medicines can impair the effect of B9 in our body.

Alcohol, for example, interferes with the absorption of folic acid in the body and increases the amount of folic acid that is eliminated through the urine.

Therefore, it is very common that alcoholics have a higher incidence of folic acid deficiency and need to resort to supplements.

The excessive use of alcohol and specific medications impair the absorption of folic acid in the body.

In addition, some medications, such as anticonvulsants and rheumatism medications, can also interfere with the absorption of folic acid in the body.

Therefore, if you are taking any substance or medication, we recommend that you consult a specialist before you start folic acid supplementation.

Is folic acid fattening?

Folic acid is not fattening because it has no calories and because it is water-soluble, it is not stored in excess by the body. In other words, even if consumed in excess, part of the folic acid is eliminated through the urine.

However, vitamin B9 deficiency can decrease appetite or even cause digestive problems such as diarrhoea, for example.

Mulher medindo com fita métrica e barriga, segurando prato de salada.

Folic acid does not make you fat, but it does rebalance your normal weight. (Source: / Pexels)

By using vitamin B9 supplementation to correct the deficiency, the body resumes the correct body weight, which can, but should not, be confused with the process of putting on weight.

In other words, like all the B-complex vitamins, folic acid is a very important nutrient for the metabolism and must be at adequate levels for those who wish to lose weight.

What are the consequences of an excess of folic acid?

As it is a water-soluble vitamin, the regulation of the amount of folic acid in the organism is well controlled. This means that there is no problem if you consume folic acid through food.

However, prolonged or excessive intake of folic acid supplementation in capsules can cause health problems ranging from mild to severe.

Prolonged consumption or over 5000 mcg of folic acid per day can cause serious health problems.

Among the problems that an excess of this vitamin can cause is a deficiency of vitamin B12. And as a consequence of this deficiency, serious problems can occur in the nervous system, as well as anaemia.

That is why, as we saw, it is highly recommended to use the B9 supplement in association with other B-complex vitamins, precisely to avoid an imbalance in the rates of these nutrients in the body.

Other complications that can occur in your health due to excessive consumption of folic acid supplements are:

  • Digestive problems
  • Stomach pain
  • Nausea
  • Skin reactions (hives)
  • Vitamin B12 deficiency
  • Anaemia

What are the advantages of folic acid supplementation?

The benefits of folic acid supplementation are numerous. As we have seen, this vitamin is responsible for strengthening the immune system and participating in the correct formation of the nervous system of babies.

In addition, vitamin B9 promotes good brain health, preventing problems such as depression.

Another advantage is that folic acid also prevents anaemia, since it stimulates the formation of blood cells; and prevents cancer. It also fights heart diseases, such as heart attack, for example; strengthens hair and nails, and helps prevent skin problems.

Casal feliz.

Correct levels of folic acid benefit the immune system and ward off depression and anaemia. (Source: J carter / Pexels)

On the other hand, folic acid also has its drawbacks. The main one is that long-term overuse of the supplement can cause serious health problems, including deficiency of other vitamins in the body.

In addition, incorrect use of the vitamin B9 supplement can also cause health problems such as digestive and skin problems.

Below, you check out the main advantages and disadvantages of folic acid supplementation:

  • Participates in the formation of the fetal nervous system during pregnancy
  • Participates in cell division and blood cell formation
  • Strengthens the immune system
  • Good for heart, brain, skin, nails and hair
  • Prevents cancer, depression and anaemia
  • Controls the evolution of vitiligo
  • Too much causes vitamin B12 deficiency
  • Incorrect use causes health problems

How much does it cost?

The price of folic acid supplements varies according to the brand manufacturers, composition, dosage and quantity. However, in general, we can say that you will find folic acid costing between £ 16 and £ 150.

Of course, you don’t need to buy the most expensive one. However, beware of very cheap products as the quality of the substance may not be as effective.

Purchase criteria: What you should consider before choosing folic acid

Now that you know about the benefits and care you should take when starting folic acid supplementation, you need to choose from the various products offered in the market today.

To make the best choice, in addition to the advice of your doctor, you need to know the characteristics that differentiate one product from another.

That is why we have selected the main factors you should consider before buying a folic acid supplement. They are the following:

  • Composition
  • Form
  • Dosage
  • Quantity

Below, we will explain to you each of these factors in detail so that you invest in the best folic acid supplement.


The first factor that we recommend you take into consideration before buying vitamin B9 is the composition of the supplement.

Here, you can choose between two options: folic acid in its isolated and pure version and folic acid combined with other substances and vitamins.

If you choose the nutrient in its pure and isolated version, make sure that there are no other elements included in the composition of the supplement.

But, if you prefer to buy folic acid combined with other substances, it is necessary to assess your nutritional needs to avoid damage to your health with excessive consumption.

As we have seen, one of the recommendations is to use folic acid in combination with other B vitamins. It is no wonder that one of the most popular combinations you will find is that of folic acid with vitamin B12 and iron, for example.


Next, we suggest you look at the form in which the supplement is consumed. As in most cases, folic acid can be found both in capsule and liquid form, and in rare cases, even in powder form.

To make the best choice, take into account your lifestyle and whether or not it is easy to swallow. Folic acid in capsule form is usually more convenient, allowing you to consume your daily dose on the go.

The liquid version is also practical in this sense, but unlike the capsule, this is a better option for those who have some difficulty swallowing tablets.

The powdered version of folic acid is more often found in combination with collagen and other substances.

Frasco aberto com comprimidos.

The supplement in capsule form is the most common and most convenient to consume. (Source: stecks05 / Pixabay)


Another very important factor that you should check before buying the vitamin B9 supplement is the dosage of the product.

In general, the dosage of folic acid ranges between one and two capsules that should be taken every day.

In addition, the amount of folic acid to be consumed in each dose can vary from 240mcg to 800mcg. Remember that dosage above 5000mcg per day can be highly harmful to your health.


To avoid excess, we recommend that you also take into account the quantity in each bottle, which varies greatly among manufacturers.

If you opt for the capsule version, you will find folic acid supplementation in bottles containing between 30 and 250 capsules. In its liquid form, the vitamin B9 supplement can contain between 20ml and 100ml.

(Source of the highlighted image: Maksym Yemelyanov / 123RF)