Vitamin B9 (Folic Acid)

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The Role of Folic Acid in the Body

Folic acid (Vitamin B9) is essential for the proper functioning of the body. It corresponds, among others, to the correct functioning of the nervous, hematopoietic, and cardiovascular systems. Together with vitamin B12, it helps in cell growth, development, and reproduction. Vitamin B9 synthesizes nucleic acids, the essential component of human DNA.

Folic acid regulates, forms, and matures red blood cells and converts homocysteine to methionine. It is also considered a factor that may reduce cancer risk.

It is worth mentioning that folic acid is a substance that must be supplied in the diet because the body cannot produce it on its own.

Folic Acid and the Proper Functioning of the Brain

Low levels of folic acid in the blood have been linked to poor brain function and an increased risk of dementia. Even a few lower levels of folic acid are associated with an increased risk of cognitive decline in older adults. Some studies have shown that folic acid supplements can improve brain function in people with mental disabilities and help treat Alzheimer's Disease.

A 2019 study of 180 adults with mild cognitive impairment (MCI) found that supplementing 400 mcg (micrograms) of folic acid daily for two years significantly improved overall brain function.

Another study of 121 people with newly diagnosed Alzheimer's disease treated with the drug found that those who took 1,250 mcg of folic acid daily for six months had improved cognition and reduced markers of inflammation compared to those who only took it.

Folic Acid and Heart Disease

The use of folic acid may positively affect the heart's work and may contribute to reducing the risk of developing various diseases of this organ.

Elevated levels of the amino acid homocysteine are associated with an increased risk of developing heart disease. Blood levels of homocysteine depend on both nutritional and genetic factors.

Folic acid plays a primary role in homocysteine metabolism. That is why low levels of vitamin B9 can contribute to high homocysteine levels, known as hyperhomocysteinemia. Studies have shown that folic acid supplementation can reduce homocysteine levels and, consequently, the risk of heart disease.

A review of 30 studies and over 80,000 people showed that folic acid supplementation led to a 4% reduction in heart disease and a 10% risk of stroke.

In addition, folic acid supplements may help lower high blood pressure. That is a significant risk factor for heart disease. Furthermore, folic acid supplements have been shown to improve blood flow, which may help improve cardiovascular function.

Other Health Benefits

Supplementing with vitamin B9 is also associated with the following health benefits:

Who Should Take Folic Acid?

Women who want to have a baby should take folic acid. Vitamin B9 should also be supplemented during pregnancy, at least until the 12th week. In addition, people who are extremely tired and have problems with sleep or concentration should consider the dosage of folic acid.

Folate supplements can also be given to children. Before using vitamin B9, it is worth taking blood tests and consulting a doctor who will choose the correct dose.

What is Folic Acid?

Folic Acid is needed by every cell in the body from conception to old age. It is not one chemical compound but a group of about 20 pterin derivatives. It is a vitamin belonging to the B group.

It performs several significant functions, such as participation in the process of building and repairing genes or protein synthesis. Without its participation, our body will not produce happiness hormones like serotonin.

Folate is in the tissues of many plants and animals. It was first isolated in the 1940s from spinach leaves. The name comes from the Latin word folium, meaning leaf. Physically, folic acid is a light yellow, water-soluble substance.

Folic acid synthesizes nucleic acids from which DNA, our genetic matrix, is formed. Thus, it regulates the growth and functioning of all cells. Folic acid with vitamin B12 also creates and matures erythrocytes, the so-called red blood cells. Due to its hematopoietic properties, its deficiency can lead to anemia.

Folic Acid During Pregnancy – Why is it Worth Supplementing?

Folic acid plays a significant role in fetal growth and development. Among other things, it affects the proper cell division and tissue growth. Having optimal levels of folic acid is meaningful both before and during pregnancyTrusted Source.

Supplementing with folic acid before and during pregnancy significantly reduces the risk of neural tube defects, including spina bifida (this condition occurs when the unborn baby's spine does not close completely during development in the womb, leaving the spinal cord exposed).

As a result, the nerves that control the legs and other organs fail their work. Children with spina bifida are often disabled for life and may have an anencephaly. Taking folic acid supplements during pregnancy helps prevent birth defects and enhance neurological development and the baby's brain function. Additionally, it minimizes the risk of developing autism spectrum disorders.

Folic acid is also significant for maternal health because its supplementation reduces the risk of pregnancy-related complications, including pre-eclampsia. In addition, high maternal folic acid levels are associated with a significantly reduced risk of preterm delivery.

Given the importance of folic acid to maternal and fetal health and the difficulty many women have in achieving optimal folic acid intake through diet, it is recommended that all women planning pregnancy supplement with 400-800 mcg of folic acid daily, starting at least one month before pregnancy and continued for the first 2-3 months of pregnancy.

While folic acid supplements are most important in the first few months of pregnancy, some research indicates that taking folic acid throughout pregnancy can help increase folic acid levels in maternal and cord blood. It also prevents the rise in homocysteine levels that usually occur in late pregnancy.

folic acid for healthy pregnancy

Folic Acid – Symptoms of Deficiency

Folic acid is one of the most significant vitamins for our body. It belongs to the group of B vitamins that are soluble in water. Its deficiency causes consequential dysfunctions in many parts of the body. The main symptoms of folic acid deficiency are:

In elderly people who suffer from depression and schizophrenia, the symptoms of these diseases are often exacerbated by a lack of folic acid.

A deficiency of folic acidTrusted Source in the body can lead to:

In women in early pregnancy, deficiency of this vitamin increases the risk of neural tube defects in the fetus.

Symptoms of Excess

Too high doses of folic acid are also harmful to the body. There is a famous saying that “the dose makes the poison”, and so it is with vitamin B9.

A high intake of vitamin B9 may mask other deficiencies of B vitamins, such as B12. This situation may result in several medical problems. It is worth mentioning that the effects of vitamin B9 and B12 deficiency are very similar, which is why it is so difficult to distinguish them at first glance.

Another negative factor caused by excessive absorption of folic acid is decreased concentration and mental function, especially in the elderly. It has been shown that an excess of B9 can also contribute to the deterioration of mental health.

Many women find it difficult, especially during pregnancy, to meet their needs for vitamin B9 optimally. Therefore, they are usually recommended to supplement with folic acid. However, too high a dose can increase insulin resistance and slow brain development in children. More than 600 μg of folic acid is strictly prohibited in pregnant women unless otherwise directed by the attending physician.

Excessive intake of folic acid can increase the ability of cancer cells to grow and spread, which can be especially harmful to people who have had cancer treatment. Adequate intake of vitamin B9 can paradoxically slow down or smother developing cancer cells at a very early stage. As you can see, moderation is the best measure. If you have trouble choosing the right supplements or determining the level of folic acid ingested with food, contact a clinical dietitian or physician.

Natural Sources of Folic Acid

Dark green vegetables, legumes, fruits, and cereal products obtained from whole milling are rich in folic acid.Trusted Source However, the best sources of folic acid are raw vegetables or low-processed products because high temperatures or the product's long shelf life cause vitamin B9 to disappear from food. Vitamin B9 must be supplied regularly because our body does not store it for long.

Vitamin B9 (Folic Acid): What Is, Health Benefits, Sources, and Safety

Unfortunately, it is sensitive to thermal factors. This means that it breaks down when exposed to higher temperatures and sunlight. Storing food for too long can destroy half of the folic acid it contains. The body is not able to store this vitamin for a long time. Therefore, it should be supplied daily. That's why it is advised to eat as many raw vegetables as possible, especially those in which vitamin C is also present – its addition protects folic acid to some extent from breakdown.

Folic Acid – Dietary Allowances (RDA)

Synthetic folic acid has 100% absorption in the body when consumed on an empty stomach, while folic acid found in fortified foods is only 85% absorbed. Naturally occurring folate has a much lower absorbability of about 50%.

The recommended daily allowance is:

Adults need about 400 μg of folic acid daily to make up for daily folic acid losses.

Folic Acid – Side Effects and Safety

Folic acid is probably safe for most people when taken orally.Trusted Source Most adults experience no side effects at doses less than 1 mg daily. Although doses up to 5 mg per day have been safely used in some studies, doses of folic acid more significant than 1 mg per day may cause abdominal cramps, diarrhea, rash, sleep disturbances, irritability, confusion, nausea, upset stomach, behavioral changes, skin reactions, convulsions, gas, excitability, and other side effects.

There is also a concern that taking too much folic acid over a long period can cause serious side effects. Some research suggests that taking folic acid in doses of 800 mcg to 1.2 mg per day may increase the risk of a heart attack in people with heart problems. Other research suggests that taking these high doses may also increase cancer risk, such as lung or prostate cancer.

Folic acid is safe for most people when injectedTrusted Source into the body. Most adults experience no side effects at doses less than 1 mg daily.

How to Check the Level of Folic Acid?

If you are experiencing symptoms that may indicate abnormal levels of vitamin B9, it is recommended that you undergo a blood testTrusted Source. For accurate results, the test should be taken on an empty stomach. This test can be helpful in evaluating the quality of your diet, the effectiveness of any supplements you may be taking, and a diagnostic tool for anemia. If you are taking vitamin B9 as part of therapy, it is best to take the test immediately before administering vitamin B9.


June 9, 2023
11 minutes read

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