Red blood cells

Vitamin B12 and Folic Acid – What’s the Connection?

Share!Share on FacebookShare on Google+Tweet about this on TwitterShare on LinkedInShare on RedditShare on StumbleUpon

Lots of B12 supplements boast on the packaging that they also contain folate or folic acid. But most of us don’t know what folic acid is, why it’s beneficial, or why we should pay more for an extra ingredient we’ve never heard of.

What is Folic Acid?
Folic acid is actually another B vitamin, and it sometimes goes by the name of Vitamin B9. Many supplements claim to contain ‘folate’, often referred to as the naturally occurring form of folic acid. In reality, almost all folic acid in supplements is produced synthetically.

For this article it’s easiest to use the terms ‘folate’ and ‘folic acid’ interchangeably, but there are a few key differences. If you’re interested, have a look at our Folate vs Folic Acid article.

Why You Need Folic Acid
Your body uses folic acid in lots of different ways. It’s used to synthesize, repair and methylate DNA (contained in every single cell of your body), as well as being important for rapid cell growth and division, especially during pregnancy and infancy.

Red blood cellsThis means that folate is especially important for pregnant women. Healthy levels of the vitamin can even lower the risks of certain birth defects – more on this further down.

Folate also acts as a cofactor in some internal biological reactions. Without folic acid, your body can’t form healthy red blood cells, which inevitably leads to anemia. Red blood cells transport oxygen around your body, so it’s obviously pretty important that they’re in good working order!

The Folate-B12 Connection
Folic acid, vitamin B12 and iron all undergo complicated interactions inside the body. Having an insufficient amount of any one of these nutrients may prevent the others from doing their jobs properly.Handshake

For example, the formation of healthy red blood cells requires both folate and B12. This is one of the reasons that supplements for vitamin B12 so often contain folic acid as well. It just ensures that the two vitamins are in balance and can work together properly.

The second reason to supplement both vitamins is that having too much folate can mask the symptoms of B12 deficiency, and vice versa. This masking effect can severely delay a diagnosis of either B12 or folate deficiency, with potentially serious consequences.

Many of the negative effects of these vitamin deficiencies are reversible, but they can become permanent if your body is vitamin-deficient for too long. That’s why it’s so important to always have a good internal balance of folic acid and B12.

Vitamin B12/Folate Deficiency Anemia

As the name suggests, this anemia can be caused by either a lack of vitamin B12 or by a lack of folic acid. Folate deficiency anemia is a form of macrocytic anemia i.e. it causes the body to produce abnormally large red blood cells that can’t Pregnant Womanadequately function.

The risks associated with this anemia are high, as potential complications include infertility, nervous system problems, heart conditions and problems in pregnancy. Some of these effects may be permanent, even if the patient receives suitable treatment.

Perhaps most concerning for pregnant women is the possibility of an unborn child suffering from fetal neural tube or brain defects. One of the most likely is spina bifida, incidence of which can be reduced by 70% by taking folate supplements during pregnancy.

Besides the devastating potential effects of anemia, there are other day-to-day symptoms that the patient may present. These include:

  • Lethargy
  • Malaise
  • Paresthesia (pins and needles)
  • Cognitive impairment
  • Muscular weakness
  • Shortness of breath

The most common cause of vitamin B12/folate deficiency Elderly Old Womananemia is of course simply not consuming enough B12 or folic acid.

But certain medications can also have an effect e.g. taking anticonvulsants or PPIs (proton pump inhibitors) increases the risk. More information on some of these medications can be found here.

Folate deficiency anemia is also more common in the elderly, as your body is less able to absorb vitamin B12 as it ages. This effect usually gets progressively worse from the age of 50 onwards.

Getting Enough Folate

Sources of Folic Acid
The only way to get the folate your body needs is through your diet. This generally isn’t a problem, but pregnant or breastfeeding women are recommended to supplement their folate intake, as are some diabetics and people taking epilepsy medication.

Vegans are also at a greater risk of suffering from folate deficiency than most, but fortunately dark green leafy vegetables are an excellent source of folic acid. Some of the best vegetarian-friendly folate sources include:Vegetarian Healthy Food

  • Broccoli
  • Asparagus
  • Avocado
  • Brussel sprouts
  • Peas
  • Spinach
  • Chickpeas
  • Yeast
  • Fortified foods

For the meat-eaters, liver is another great source of folic acid.

In the United States and many other countries, certain cereal crops (typically wheat) are mandated by law to be fortified with folic acid. This was originally an attempt to reduce the number of people being diagnosed with folate deficiency. It means that you may already have a higher folic acid intake than you realize.

N.B. At the time of writing, no EU countries have this mandate in place.

Recommended Daily Allowance of Folic Acid
Different sources recommend consuming various different amounts of folic acid (with 0.2mg per day being a commonly cited amount), although it’s generally thought that most people should be able to glean enough folate from their diets.

As mentioned above, certain groups are advised to supplement their intake. For example, the UK National Health Service recommends that women hoping to conceive take an extra 0.4mg of folic acid every day (on top of whatever their diet provides). This should continue from whenever they stop taking contraception until they are twelve weeks pregnant, and possibly beyond.

If your family has a history of Central Nervous System (CNS) problems, then recommended supplementation for a pregnant woman can be as high as 5mg of folate per day.

Folate Deficiency
Fortunately folate deficiency doesn’t happen overnight. It generally takes several months of consistently low folate intake before deficiency sets in. Folic acid deficiency can be very unpleasant, with a wide range of negative effects on your body, some of which could even be permanent.

Alcohol consumption is thought to increase the rate at which your body becomes folate deficient.

Symptoms of Folate DeficiencyUpset Man

  • Folate deficiency anemia (see below)
  • Glossitis (sore/swollen tongue)
  • Weakness or shortness of breath
  • Diarrhea
  • Confusion and forgetfulness
  • Depression
  • Peripheral neuropathy (nerve damage)
  • Irritability
  • Pregnancy complications

Folate Supplements
The majority of people will be able to get all the folic acid they need from their diets. But it’s worth pointing out that there’s no evidence that supplementing your diet with extra folate is harmful.

As the risks associated with folate supplementation are low and the consequences of folate deficiency are potentially serious, many otherwise  healthy, low-risk individuals supplement their folic acid intake just to be  on the safe side.

Some sources recommend supplementing your intake with no more than  1mg of extra folic acid per day, but this isn’t widely agreed upon. Because  it’s water soluble, there is a low risk of toxicity with folic acid, so any  excess folate that the body doesn’t need can easily be excreted in urine.

N.B. One important exception concerns small children and pregnant women in areas where malaria is endemic, as excess folate intake has been shown to decrease the effectiveness of one of the most common antimalarial drugs, sulfacoxine-pyrimethamine (SP).

Further Reading
If you decide to take a combined vitamin B12 and folic acid supplement, please take a look at the supplements we recommend here.

For more information on the role vitamin B12 plays in the human body, please see our article What Vitamin B12 Actually Does.

If you’d like to find out more about vitamin B12 and the different kinds you might find in your supplements, please read our article Vitamin B12 and Methylcobalamin – What Are They?

From top to bottom, images are courtesy of renjith krishnan, stockimages, David Castillo Dominici, Ambro, Serge Bertasius Photography, antpkr, Master isolated images, all at

Share!Share on FacebookShare on Google+Tweet about this on TwitterShare on LinkedInShare on RedditShare on StumbleUpon

3 thoughts on “Vitamin B12 and Folic Acid – What’s the Connection?”

Comments are closed.