Does Vitamin B12 boost Immune System Function?

Vitamin B12 is a water-soluble vitamin that is essential to your health and well-being. Without it, your immune system and many other body functions couldn’t work properly. If you are looking for ways to support healthy immune function, you need to understand the basics of vitamin B12 immune system support, how much of this vitamin you should consume, and the signs of a deficiency. Does vitamin B12 boost immune system function? Keep reading to learn more!

Vitamin B12 Immune System Support

Vitamin B12 is an essential nutrient. Your body needs it for a wide range of functions, but because your body can’t make it, you must get B12 from your diet or supplements.

Even a marginal deficiency in any essential nutrient, like B12, can compromise your immune function. 

A deficiency in vitamin B12 can affect the immune system in a few different ways. It can:

  • Alter the production of nucleic acid
  • Interfere with protein synthesis
  • Hinder immune cell activity
  • Interfere with metabolic processes, such as methylation

Inefficient methylation can eventually develop into systemic inflammation that contributes to disease. 

Vitamin B12 also plays a role in white blood cell production. White blood cells are crucial to proper immune system function.

does vitamin b12 boost immune system function woman sitting on couch in light purple sweater blowing nose into tissue with white blanket over legs bright background

Does B12 Boost Immune System Function?

Vitamin B12 may indirectly boost your immune system function. This essential vitamin plays a role in a number of important body functions that all contribute to healthy immune function.

Vitamin B12:

  • Helps your body make DNA
  • Helps keep your blood cells and nerves healthy
  • Helps prevent a special type of anemia, called megaloblastic anemia
  • Keeps homocysteine levels in check

Ultimately, B12 is an essential nutrient that your body needs to function properly. Without it, many functions, including your immune response, may not run optimally. 

Signs and Symptoms of a Vitamin B12 Deficiency

What happens if your body doesn’t get enough B12? A deficiency in this vital nutrient can cause a number of issues, including:

  • Weakness
  • Fatigue
  • Tingling and numbness
  • Poor immune system function
  • Nerve problems, including pain
  • Depression
  • Memory loss and confusion

If left untreated, a B12 deficiency can damage the nervous system, even if you don’t have anemia. 

Scientists are still learning about how B12 affects the body, but chronic deficiencies can cause a number of problems.

  • May contribute to dementia: People with dementia often have high amounts of homocysteine in their blood. Vitamin B12 can help regulate homocysteine levels. 
  • May contribute to heart disease: B12 may not be used to treat or even prevent heart disease, but maintaining healthy levels of this vital nutrient can keep homocysteine levels in check. High levels of homocysteine have also been linked to an increased risk of stroke or heart attack.

What Causes a B12 Deficiency?

To understand how a B12 deficiency develops, you need to understand how your body absorbs it. This water-soluble vitamin goes through a three-step process before being absorbed by the body.

  • The hydrochloric acid in your stomach separates B12 from the protein it’s attached to in your food.
  • Next, B12 combines with intrinsic factor, a protein made by your stomach.
  • Finally, the body absorbs this nutrient.

Any interference with this process can make it difficult or impossible for your body to absorb B12. 

If you have pernicious anemia, for example, your stomach cannot make intrinsic factor. This means that your body has a hard time absorbing vitamin B12 from foods and supplements.

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Deficiency can also be caused by diet. Vitamin B12 is found almost exclusively in animal products. Without eating fortified plant foods, strict vegans will not get enough B12 from diet alone. Supplements can help fill the gap.

Other causes of B12 deficiency include:

  • Aging. Many older adults are lacking the hydrochloric acid needed to absorb B12 in foods.
  • Gastrointestinal surgery and digestive disorders, such as Chron’s disease or celiac disease. 

Any interference with healthy digestion function can hinder your body’s ability to absorb vitamin B12.

How Much Vitamin B12 Do You Need?

The amount of B12 that you need will depend on your age. According to the NIH, daily recommended intakes are as follows:

  • 0-6 months: 0.4 mcg
  • 7-12 months: 0.5 mcg
  • 1-3 years of age: 0.9 mcg
  • 4-8 years of age: 1.2 mcg
  • 9-13 years of age: 1.8 mcg
  • 14-18 years of age: 2.4 mcg
  • Adults: 2.4 mcg
  • Pregnant women: 2.6 mcg
  • Breastfeeding women: 2.8 mcg

Sources of Vitamin B12

Vitamin B12 is found naturally in animal foods as well as fortified foods. Some of the best food sources of this nutrient include:

  • Fish
  • Beef liver
  • Clams
  • Eggs
  • Milk
  • Cheese and other dairy products
  • Poultry
  • Meat 
  • Specially fortified breakfast cereals

Vitamin B12 supplements can help ensure that you get your daily recommended intake without having to change your diet. You can find specific B12 supplements, but multi-vitamins almost always contain this nutrient.

Supplements can come in capsule form or even sublingual forms. There is no evidence that one form is more easily absorbed than the other, so it’s really a matter of personal preference.