Written by Dr. Inez Van Roy on
August 15, 2021
Reading Time: 6 minutes

Medically Reviewed by our Medical Affairs Team

Written by Dr. Inez Van Roy on:

Does Vitamin B12 Help With Brain Fog?

You’ve been having a foggy brain quite frequently lately, even though you’ve been hydrating, exercising, eating the right food, and getting enough sleep. Some people often say that you may need to take vitamin B12. So, does B12 help with brain fog? Really? 

Well, I’ll answer that question and more. So, keep on reading. 

What is Vitamin B12?

Vitamin B12, also commonly known as cobalamin, is a nutrient that you need to keep your nerve cells and red blood cells healthy. It also helps your body create DNA, the code that exists in all of your cells. 

B12 is also essential in preventing megaloblastic anemia – a condition in the blood that makes people endlessly weak and tired. 

Vitamin B12 is water-soluble that is naturally present in some types of food, but it is also often available as a chewable for dietary supplements or prescription medication. 

Mental Health Benefits of Vitamin B12

Vitamin B12 is crucial in keeping your entire nervous system healthy, most especially your brain – B12 helps you keep your cognitive capabilities functioning well. Therefore, you need vitamin B12 to help you create new memories, concentrate, and focus on the tasks at hand. 

In fact, people with vitamin B12 deficiency are prone to depression – this makes a lot of sense because you need B12 to form a healthy dose of dopamine and serotonin, which are the much-needed mood-boosting neurotransmitters. 

Studies also found that vitamin B12 can help fight schizophrenia symptoms, such as emotional inexpressiveness, apathy, and social withdrawal. 

Other researchers also suggest that there is a strong link between vitamin B12 deficiency and psychiatric disorders, especially Alzheimer’s and dementia – the researchers strongly recommend that patients’ B12 levels must be monitored closely for life. 

Vitamin B12 Benefits for Alzheimer’s and Dementia

Several studies have found that most seniors who are diagnosed with Alzheimer’s or dementia are primarily vitamin B12-deficient, that most of them have B12 as their ONLY deficiency in nutrients, and that they have made incredible recoveries after their lack of B12 has been appropriately addressed. 

Of course, multiple diagnoses also happened because vitamin B12 deficiency symptoms closely mimic those of the mental health issues. 

In fact, there is this exciting study from the University of Oxford that found evidence that having a cocktail of vitamin B-complex is incredibly beneficial in preventing and treating Alzheimer’s. 

The researchers stated that taking vitamin B12 with folic acid and vitamin B6 can dramatically reduce the shrinkage of the brain, especially in the area of the brain that is most affected by Alzheimer’s. They have also noticed an increase in brain function improvement of the patients. 

Other Benefits of Vitamin B12

There are tons of mental health and physical health benefits that vitamin B12 offers, but here are the most common B12 benefits according to science: 

  1. Vitamin B12 helps you fight and prevent anemia by forming healthy red blood cells. 
  2. Healthy levels of B12 prevents miscarriages, major birth defects and helps you maintain a healthy pregnancy throughout.  
  3. Vitamin B12 helps you prevent osteoporosis and support bone health effectively. 
  4. B12 can reduce your risk of having macular degeneration, an eye disease that primarily affects your central vision. 
  5. Vitamin B12 helps you prevent depression and regulate or even improve your mood. 
  6. B12 helps your brain fight the loss of neurons. 
  7. People with healthy levels of vitamin B12 have more energy than those who are B12-deficient. 
  8. Vitamin B12 helps decrease homocysteine, a common amino acid linked to an increased risk of heart failure. 
  9. B12 supports the healthy growth of nails and hair as well as developing healthy skin. 

Vitamin B12 Food Sources

Our bodies cannot produce B12 naturally, just like how it cannot make most vitamins and minerals. So, we can only get vitamin B12 from food or dietary supplements.

B12 is commonly found in animal products, such as the following: 

  • Eggs
  • Meat
  • Dairy
  • Poultry
  • Seafood
  • Fish
  • Pork

However, it is essential to note that even though vitamin B12 is easily found in animal products, plenty of factors can hinder its absorption, such as your gastrointestinal health, age, and medications. 

And according to a study, B12 can be best absorbed from animal livers and clams because they contain 100 times more vitamin B12 than eggs and 60 times more than beef.  

This is why if you are a vegan or vegetarian, I strongly recommend that you take chewable supplements for vitamin B12. 

Vitamin B12 Plant Source for Vegans & Vegetarians 

This is a caveat to fellow vegans and vegetarians or anyone who just wants to eat plant-based. There are many B12 dietary supplements that are causing even more harm because they have been allegedly extracted from plant sources. 

The truth is that brewer’s yeast, green algae like spirulina, and fermented soy products only contain B12 analogs similar to, but not the same, vitamin B12 that our body needs. 

The worst part is that these pseudo vitamins often block the intake of genuine vitamin B12 by binding with B12 receptors, thereby making B12-deficiency even more. 

However, studies show that the only substantial plant source of vitamin B12 is the sea vegetable nori (Porphyra umbilicalis). So, make sure that your B12 supplement comes from this sea plant.  

I don’t want to promote any B12 products, so I recommend you visit vegansociety.com and veganhealth.org for a plethora of science-backed vitamin B12 information.  

Vitamin B12 Supplement Dosage

Average adults have the Recommended Dietary Allowance (RDA) of 2.4 mcg (micrograms) of B12 per day. 

However, you might see on other B12 supplements that they contain way more than the RDA, commonly at 500 to 5000 mcg, but this is actually reasonable because our body absorbs only 2% of vitamin B12 in dietary supplements. 

But suppose you have moderate to extreme B12 deficiency. In that case, your doctor might suggest injectable vitamin B12 for quick absorption and increase the level of B12 in your body, especially if you have digestive problems, anemia, or permanent nerve damage. 

Vitamin B12 Side Effects

Vitamin B12 supplements are generally considered to be VERY safe that doses as high as 2 mg (milligrams) daily do not cause any harmful side effects

B12 supplements are, indeed, safe to be taken by mouth or applied to the skin, or sprayed into the nose, or given by IV or shot. 

Signs You’re Low on Vitamin B12

There are multiple signs that can help you determine that you may be B12-deficient, and here are the most common ones: 

  • Numbness: your legs, feet, and hands are often numb, and you feel these “pins & needles” all around.
  • You feel colder than usual: you don’t have enough red blood cells that help move oxygen around your body, making you shiver. 
  • Brain fog: the lack of B12 causes brain fog, which may also lead to confusion, memory problems, depression, and even dementia. 
  • Weakness: you often feel lightheaded, tired, and depleted in strength. 
  • Smooth tongue: the tiny bumps on your tongue, also known as papillae, are wasting away, and your tongue starts to appear glossy and smooth. 
  • Mouth sores: you are prone to tongue and gum ulcers, so avoid ingredients like chili powder, vinegar, citrus, and other hot spices. 
  • Heart palpitations: you feel your heart often make sudden races or skip a beat, which you can primarily feel on your neck or throat. 
  • Digestive problems: you might have trouble defecating, or lose your appetite, or drop an alarming amount of weight. 

A Few Reasons Why You’re Short on Vitamin B12

There are a few reasons why you can still be short of B12 even though you’ve been taking the supplements religiously. Here are the most common reasons; 

Your Age 

When we get older, our body loses its total capacity to absorb vitamin B12 effectively. So, I highly recommend that you consult your doctor and get you tested for vitamin B12, especially if you’re starting to see or feel the B12-deficiency symptoms listed above, including some brain fog symptoms

The Weight Surgery You Might Have Undergone 

Gastric bypass, one of the most common weight-loss surgeries, makes your food bypass some parts of your small intestine and stomach, where vitamin B12 is usually broken down into a usable and beneficial nutrient. 

So, you have to monitor your B12 levels if you had this kind of surgery, and your doctor might recommend injectable B12 if needed. 

The Medications You’re Taking 

There are several drugs that can reduce your vitamin B12 or make it harder for your body to absorb the nutrient effectively. Here are some of these medications: 

  • Metformin for diabetes
  • Chloromycetin or Chloramphenicol for infection 
  • Tagamet or cimetidine and Zantac or ranitidine for peptic ulcer 
  • Proton pump inhibitors, such as Prilosec or omeprazole and Prevacid or lansoprazole 

So, make sure to tell your pharmacist and doctor about all the supplements and medications you’re taking so that they do not counter-attack each other.

Who’s at Risk for Vitamin B12 Deficiency

The following people are at risk of being vitamin B12-deficient: 

  • Vegetarians and vegans 
  • Seniors who are above 60
  • People taking acid-suppressing drugs 
  • People with diabetes who take Metformin 
  • People who suffer from chronic digestive disorders, such as irritable bowel syndrome, Chron’s, or celiac disease
  • People who have eating disorders 
  • People who underwent weight-loss surgeries 
  • People who have bacteria-causing ulcers, such as H. pylori
  • People who abuse nitrous oxide and alcohol 
  • HIV-positive people

If you are one of the people listed above, I highly suggest that you consult your doctor about B12-deficiency immediately. 

So, Does B12 Help with Brain Fog?

Several studies and research that I have linked and listed in this blog post suggest that vitamin B12 does help with brain fog and other mental health issues

Apparently, if B12 helps fight risks for Alzheimer’s, dementia, and other psychiatric disorders, how much more for brain fog, right?

So, feel free to bookmark this article and share it with people you know who might be suffering from B12 deficiency and brain fog.

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