Can B12 Deficiency Cause Brain Fog and Memory Issues?

Brain fog refers to forgetfulness, difficulty concentrating, confusion, and other symptoms affecting your cognitive function. And while brain fog can be caused by things like stress or lack of sleep, it can also be a sign of b12 deficiency. So can b12 deficiency cause brain fog?

Well, vitamin B12 is essential for proper nerve function and development. When you don’t have enough of it in your system, those functions start to break down – which leads to the symptoms of brain fog.

Learn more about how can b12 deficiency cause brain fog and ways to treat it.

Table of Contents

What Is Vitamin B12?

If you’re like most people, you probably don’t think about vitamin B12 much. But this essential nutrient plays a vital role in keeping your body and brain healthy.

B12 is a water-soluble vitamin that’s found in animal-based foods such as meat, poultry, fish, and eggs. It’s also available in supplement form.

B12 is important for many functions in your body, including the formation of red blood cells, the maintenance of your nervous system, and the production of DNA.

A lack of B12 can lead to a condition called pernicious anemia, which can cause fatigue, weakness, and other symptoms.

B12 deficiency can also cause cognitive problems such as memory loss and brain fog.

If you think you might be deficient in B12, talk to your doctor. They can order a blood test to check your levels.

If you are deficient, they may recommend supplements or shots.

Causes of B12 Deficiency

One of the most common causes of vitamin B12 deficiency is pernicious anemia which is an autoimmune disorder that destroys the stomach lining.

This lining is necessary for the absorption of vitamin B12.

Vitamin B12 deficiency is also common in:

  • Vegans or vegetarians who don’t eat foods that are fortified with vitamin B12.
  • People with gastrointestinal disorders like Crohn’s disease or celiac disease.
  • People who have had surgery to remove part of the stomach or intestine.
  • Older adults.

can b12 deficiency cause brain fog


Symptoms of vitamin B12 deficiency include:

  • Fatigue
  • Weakness
  • Lightheadedness
  • Pale skin
  • Irritability
  • Memory loss
  • Difficulty concentrating
  • Tingling in the hands and feet
Key Takeaway: A lack of vitamin B12 can lead to anemia and neurological problems.

Mental Symptoms of Vitamin B12 Deficiency

If you’re feeling forgetful, having trouble concentrating, or just generally feeling mentally foggy, you could be experiencing symptoms of a vitamin B12 deficiency.

Though vitamin B12 is found naturally in animal products like meat and eggs, many people don’t get enough of it in their diets. This can lead to a host of problems, including brain fog.

Brain fog can be a frustrating symptom of a vitamin B12 deficiency. You might feel like you can’t think clearly or that your memory is slipping.

Thankfully, vitamin B12 supplements can help to clear up brain fog and improve your overall cognitive function.

Can B12 Deficiency Cause Brain Fog?

While there can be many causes of brain fog, one potential cause is vitamin B12 deficiency.

Vitamin B12 is a nutrient that’s essential for proper brain function. It helps to produce the myelin sheath that protects nerve cells, and it’s also involved in the synthesis of neurotransmitters like serotonin and dopamine.

A lack of vitamin B12 can therefore lead to cognitive problems like brain fog.

Key Takeaway: Vitamin B12 is essential for proper brain function and a lack of it can cause cognitive problems like brain fog.

How to Treat Brain Fog

A balanced diet is key to maintaining good health, both physically and mentally. For many people, a balanced diet means eating a variety of foods from each of the food groups in moderation. However, for some people, a balanced diet may mean following a specific diet plan that eliminates certain foods or food groups.

No matter what your definition of a balanced diet is, there are some general guidelines that can help you create a healthy, balanced diet for yourself.

1. Eat a Variety of Foods

Eating a variety of foods is important because it helps you get all of the nutrients your body needs. nutrients are substances that your body needs to function properly. They include vitamins, minerals, proteins, carbohydrates, fats, and water.

2. Choose Foods That Are Low in Trans Fat

Saturated fat, trans fat, and cholesterol are found in animal products such as meat, poultry, and full-fat dairy products. They can also be found in some vegetable oils, such as coconut oil and palm oil. Eating too much trans fat can raise your risk for heart disease and other health problems.

3. Eat Plenty of Fruits and Vegetables

Fruits and vegetables are good sources of vitamins, minerals, and fiber. They can also help you fill up fewer calories. The 2015-2020 Dietary Guidelines for Americans recommend that adults eat at least 2 cups of fruit and 2½ cups of vegetables each day.

4. Choose Whole-Grain Foods

Whole-grain foods are made with all of the parts of the grain. They include the bran, the germ, and the endosperm. Whole-grain foods are a good source of fiber and other nutrients.

5. Limit Your Intake of Sugar and Salt

Too much sugar and salt can lead to health problems, such as obesity, type 2 diabetes, and high blood pressure. The 2015-2020 Dietary Guidelines for Americans recommend that adults consume no more than 10% of their daily calories from added sugars and that they limit their sodium intake to less than 2,300 mg per day.

6. Drink Plenty of Water

Water is essential for good health. It helps your body function properly and maintain a healthy weight. The 2015-2020 Dietary Guidelines for Americans recommend that adults drink 8 or more cups of water each day.

Following a healthy, balanced diet can help you feel your best and maintain your health. If you have any questions about how to create a healthy diet for yourself, talk to a registered dietitian or your healthcare provider.

Key Takeaway: A vitamin B12 deficiency can cause brain fog. The best way to treat it is by taking a supplement or eating foods that are rich in vitamin B12.


Can B12 deficiency cause brain fog? Yes, B12 deficiency can cause brain fog. If you’re experiencing any of the symptoms associated with this condition, it’s important to see your doctor and get a diagnosis.

With treatment, you can improve your cognitive function and overall health.