How can ordinary folic acid harm you?

Many of us associate folic acid with products for pregnant women. However, supplementing with vitamin B9, one form of which is folic acid, can be beneficial for many people. At the same time, it can also be harmful if we choose the wrong supplement. Even brands considered premium contain ordinary, cheap folic acid, which is not absorbed. Accumulating in the blood, it can have a toxic effect on our body. But let's talk about everything in order.

Folic acid and folates – what is the difference?

Vitamin B9 is necessary for the proper functioning of every human body. It takes part in cell division and the formation of DNA structures. It occurs in nature and in our bodies in the form of folates . This is the collective name for various forms of this vitamin. In other words, folate is natural vitamin B9 . Folic acid, in turn, is its synthetic equivalent . Does that mean it's worse? It is an inactive form that the body must convert into folates to be able to use it. And this is the key issue. Not all of us are able to accomplish this transformation of folic acid.

Up to 60% of people may not absorb regular folic acid.

Synthetic folic acid enters our body from dietary supplements or food products enriched with it (e.g. breakfast cereals or bread). Then, 4 stages of transformation await him . Ultimately, the active compound 5-MTHF (methylfolate) should be created ¹ , which the body can use for its needs. These transformations take place with the participation of enzymes, digestive organs, the liver and with the support of certain genes . However, scientists say that up to 60% of people may have a genetic mutation that makes the entire process impossible ² . This is a mutation of the MTHFR gene, which is often associated with an increased risk of miscarriages in women, as well as hypertension, thrombosis, mental disorders and some types of cancer ³ . In all these health problems, the lack of folates available to the body plays an important role if we do not provide them in an appropriate, active form from the outside.

What happens to the folic acid that we have swallowed but cannot absorb?

Let's say we have this mutation or we can't convert regular folic acid into active folate for other reasons. What happens to it in our body? Accumulates in the blood . If a pregnant woman supplements regular folic acid and cannot metabolize it, its inactive form also passes to the baby through the placenta. ⁴ . By taking subsequent doses of regular folic acid or eating fortified foods, we accumulate more and more inactive vitamin B9 in the blood. ^5.6 . This may have a toxic effect . If the level of folic acid in the blood is too high, it can lead to:

• slowed brain development in 4-5-year-old children ⁷ and a greater risk of insulin resistance ⁸ in children aged 9-13 if the mother supplemented too high doses of folic acid during pregnancy;
• increased development of cancer cells ^{9 , 10} and recurrence of certain types of cancer (e.g., colorectal ¹¹ or prostate ¹² );
• masking the symptoms of vitamin B12 deficiency and associated megaloblastic anemia ¹³ . This condition permanently damages nerve cells and brain function ¹⁴ ;
• brain function disorders in older people, especially if they also have low levels of vitamin B12 in the blood ^15,16 .

An important moment. Even small doses of synthetic folic acid (e.g. daily "standard" 400 mcg) can accumulate in the blood and be dangerous to health if we are unable to metabolize them. ¹⁷ . Researchers found inactive folic acid in blood samples of virtually all U.S. children, teens and adults who took supplements (2007-2008 study) ¹⁸ .

What type of folate is best?

Since synthetic folic acid can harm many people, maybe it is worth just eating more products naturally containing folate ? Unfortunately, this solution also has its weak points . Yes, some vegetables, especially green and leafy ones, contain relatively much folate. However, supplementing them only through diet would mean that we have to eat at least 0.4 kg of broccoli or 0.8 kg of Brussels sprouts every day. ¹⁹ . If we haven't done this recently, we may be deficient and need even larger amounts of folate.

Another problem - scientists agree that folates from food are not well absorbed by the body ²⁰ . To transform into an active form, they also have to go through several stages and need, among others: special enzymes secreted by intestinal cells ²¹ . Genetic mutations can disrupt this process, as with regular folic acid. It is estimated that our body is able to use only 50% of folates from food ²² .

What remains? Provide the body with the most active form from the outside that the body can use immediately. No transformation required.

Quatrefolic is the most bioavailable form of folate on the market.

Currently, active folic acid can be found on the dietary supplement market in the following forms:

• Calcium L-methylfolate (aka Metafolin or calcium salt (6s)-5-MTHF)
• Quatrefolic (also known as Folate IV generation or glucosamine salt of (6s)-5-MTHF acid).

What is the difference between these 2 forms? The first one is less bioavailable and stable only at temperatures of 2-8°C. It is also not very soluble in water. The second one, Quatrefolic, is more stable ( even at 25°C) and bioavailable . Preclinical studies showed that after supplementation, the concentration of Quatrefolic in the blood was 20% higher than that of calcium L-methylfolate. Quatrefolic is also 100 times more soluble in water than calcium salt (6s)-5-MTHF ²³ .

The above facts prove that Quatrefolic is the best form of folic acid available on the market. The body can use fourth-generation folates immediately, regardless of gene mutations and other health problems. It is also the only form of folate that penetrates the blood-brain barrier ²³ . Quatrefolic is an innovative and patented ingredient, and its safety has been confirmed in Europe (EFSA, European Commission Novel Food approval), USA (GRAS, FDA approval), Australia, South Korea and China ²⁴ .

Why is it worth supplementing folate?

According to research, most adult Poles do not consume the recommended daily amount of folate ²⁵ . In addition, long-term food storage and thermal processing may reduce their content in food. Additionally, their absorption from the diet may be impaired by digestive problems, alcohol consumption and cigarette smoking . The absorption of folates is also blocked by some medications , including: non-steroidal anti-inflammatory drugs (e.g. ibuprofen, aspirin), drugs that affect the acidity of the gastrointestinal tract or anti-tuberculosis drugs ²⁶ . Therefore, dietary supplements can help replenish the necessary vitamin B9, which humans do not produce and cannot obtain in sufficient quantity even from a varied diet.

The benefits of folate supplementation can be experienced by people at various stages of life. Folates support the functioning of our immune system . Their deficiency may cause chronic inflammation , which leads to various diseases, including life-threatening ones ^27,28,29 . Vitamin B9 also participates in blood production and protects heart health , supports the prevention of coronary heart disease, thrombosis, atherosclerosis, heart attack and stroke. ^30,31,32,33 . Folate helps in states of constant fatigue ³⁴ and support cognitive function (e.g. memory) ^35,36 . They may also delay brain aging and lower the risk of dementia ³⁷ . During pregnancy, folates reduce the risk of fetal developmental disorders and the resulting pregnancy complications and miscarriages by as much as 70%. ^38,39,40 .

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