What Is Vitamin B12?

Essential Nutrient for Blood and Nervous System Function

Vitamin B12, also called cobalamin, helps the body produce energy by converting carbohydrates into glucose. B vitamins are water soluble, which means that the body doesn’t store them and they need to be replenished regularly by absorbing them from food.

The hydrochloric acid in the stomach separates vitamin B12 from the protein in food. From there, vitamin B12 is absorbed by the body and combined with a protein that is made by the stomach called intrinsic factor.

If a person can’t naturally make the intrinsic factor, they have pernicious anemia. This means that they have difficulty absorbing vitamin B12 from dietary supplements and all foods.

Vitamin B12 also helps the nervous system function effectively. Working together with vitamin B9 (folate), it helps iron function better and helps the body to make healthy red blood cells. Together, folate and vitamin B12 work to produces S-adenosylmethionine (SAMe), a compound that assists with mood and immune function.

Foods that are good sources of vitamin B12
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Health Benefits

Vitamin B12 has many health benefits. It is known to help memory, mood, the nervous system, iron levels, heart health, hair, nails, skin, and much more.

Blood Health

Vitamin B12 is an important factor in helping the body produce healthy red blood cells. When the body is deficient and had low levels of vitamin B12, this can cause the red blood cells to improperly develop.

The red blood cells become larger and irregular in shape. This prevents the red blood cells from moving from the bone marrow to the bloodstream. This is how megaloblastic anemia is caused.

Anemia can cause weakness, fatigue, and other ailments down the line because your body doesn’t have enough red blood cells to give oxygen to your organs.

Brain Health

Studies show that vitamin B12 can help with brain and nervous system function, memory, boosts mood, and helps with depression. Research has concluded that studies of patients and the general population with depression have both low folate and low vitamin B12. Other studies have shown that vitamin B12 deficiency leads to poor memory. 

Skin Health

Vitamin B12 is known to help the skin, hair, and nails. Deficiency in the vitamin leads to discolored patches, skin hyperpigmentation, vitiligo, reduced hair growth, and more.

Heart Health

Studies have shown that vitamin B12 is known to reduce homocysteine levels in the blood. This is an amino acid that is aligned with an increase in heart disease. Researchers found that people who have modestly elevated homocysteine levels have higher rates of heart attack and stroke.

Sources

You can get vitamin B12 through supplements and foods. Some food that naturally have vitamin B 12 include:

  • Lamb
  • Beef
  • Chicken breast
  • Clam
  • Salmon
  • Sardines
  • Trout
  • Tuna
  • Milk
  • Eggs
  • Ham
  • Plain Greek yogurt
  • Fortified nutritional yeast

Suggested Doses

The recommended dietary allowance of vitamin B12 is 2.4 micrograms a day. A normal range varies between 200 to 900 picograms per milliliter (pg/ml).

Experts share that if a vitamin B12 value is less than 200 pg/ml this would be considered a vitamin B12 deficiency. A medical professional can administer a blood test to measure vitamin B12 levels.

Deficiency

When individuals have a deficiency in vitamin B!2 this can cause tiredness, weakness, numbness and tingling in fingers and toes, and more.

Some of the individuals who are likely to be deficient in vitamin B12 are older people who don’t produce adequate hydrochloric acid in their stomach to absorb the vitamin naturally through food.

Individuals who have digestive disorders such as Crohn's disease and celiac disease may be deficient in B12 due to decreased absorption, as man people who had weight loss surgery or gastrointestinal surgery.

Other individuals include people who don’t consume many animal products. Vegetarians and vegans are should check their vitamin B12 levels.

When vitamin B12 levels are low, the body cannot produce enough healthy red blood cells, leading to anemia. Red blood cells carry oxygen to parts of the body. Without enough cells delivering oxygen to your tissues and organs, the body will not function properly.

Symptoms of vitamin B12 deficiency include:

  • Irregular heartbeats
  • Weight loss
  • Tender tongue
  • Mood swings/Irritability
  • Anemia
  • Numbness or tingling in your hands and feet
  • Fatigue
  • Shortness of breath
  • Dizziness
  • Vitiligo
  • Pale or yellowish skin
  • Muscle weakness
  • Unsteady movements
  • Memory loss
  • Confusion

Risks and Interactions

Although research has shown there is no risk in taking vitamin B12, it is important to contact your doctor before you begin taking any vitamin, mineral, or supplement. A medical professional can best determine if it is a need for you at this time.

Research has shown that certain medications and vitamin B12 can interact with some medications. These are known to interfere with the body’s absorption of vitamin B12. These examples are quoted from the National Institute of Health:

  • Chloromycetin (chloramphenicol): This is an antibiotic that is used to treat some infections.
  • Proton pump inhibitors: These are used to treat acid reflux and peptic ulcer disease, and include Prilosec (omeprazole) and Prevacid (lansoprazole).
  • Histamine H2 receptor antagonists: These are used to treat peptic ulcer disease and include Tagamet (cimetidine), Pepcid (famotidine), and Zantac (ranitidine).
  • Metformin: This drug used to treat insulin resistance and diabetes.

Before you take vitamin B12 talk to your doctor or healthcare provider and tell them about any medication, vitamin, and or supplements you are taking.

A Word From Verywell

Vitamin B12 is an essential nutrient in the human diet. It's critical for the development and normal functioning of many organs in the body. You should try to get your daily recommended intake of vitamin B12. Try to enjoy time in the sun as much as possible and eat foods that naturally have vitamin B12.

If you are not sure if you have enough vitamin B12 talk to your doctor about getting a blood test, adding the proper foods to your diet, and supplements. As with most other vitamins and nutrients, it may be best to get your daily requirements from food sources. If you need additional supplements or information, contact a healthcare professional.

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Article Sources
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