7 Reasons Why Vitamin B12 Is Important

May 16, 2024
Chalkboard with B12 Vitamin written on it

Vitamin B12 deficiency is common and underdiagnosed, even though excess B12 is stored in the liver. Vitamin B12 is found mainly in animal products, fortified breakfast cereals, and nutritional yeast. People who take certain medicines, eat a vegan or vegetarian diet, or have had stomach problems in the past may need to supplement their vitamin B12 (Ankar, 2022).

Human physiology is complex. While scientists have identified several roles for vitamin B12 in the body, there are likely hundreds of others that have not been identified or are attributed to another vitamin or mineral alone. Imagine the most complex spider web you can think of. If you had to write a chemical reaction on each thread, you wouldn’t begin to approximate all the chemical reactions occurring in your body. Read on to find out why Vitamin B12 is important.

Helps Maintain Energy Levels

Red blood cells carry oxygen to your body cells and remove carbon dioxide. When red blood cells aren’t functioning properly, your body tissues may not achieve optimal oxygen levels, which can cause fatigue. 

Healthy red blood cells have a biconcave disc shape. This shape holds the most hemoglobin possible and provides the most surface area for oxygen and carbon dioxide to move through. Healthy red blood cells are flexible and fold as they move through the smallest blood vessels. 

If a person does not have enough vitamin B12, their red blood cells become larger and more oval because vitamin B12 affects how DNA and RNA work in their cells. When DNA and RNA production lags, it causes changes in red blood cell composition. These larger cells cannot move as easily from the bone marrow, where they are produced, to the blood vessels, where they circulate. This is called megaloblastic anemia (Hariz, 2022). 

Many of the symptoms associated with vitamin B12 deficiency are due to anemia. Symptoms associated with anemia include:

  • Fatigue
  • Pale skin
  • Cold fingers and toes
  • Weakness
  • Dizziness
  • Shortness of breath
  • Palpitation
  • Sore, glossy tongue
7 Reasons Why Vitamin B12 Is Important

Involved In Heart Health

Vitamin B12 is involved in several key chemical reactions, including:

  • Conversion of homocysteine to methionine

Methionine is needed to make S-adenosylmethionine, which is a methyl donor that can be used in almost 100 different chemical reactions. Some of these reactions are involved in DNA, RNA, and protein metabolism. 

Low vitamin B12 levels are associated with high homocysteine levels, which can have effects throughout the body (Clarke 2003). High levels of homocysteine are linked to early-onset heart disease. Low vitamin B12 and folate levels and kidney disease cause high homocysteine (Vizzardi 2009). Randomized clinical trials have shown that vitamin B12 and folate supplements can lower homocysteine levels but not cardiovascular disease risk (NIH 2022). 

  • Conversion of methylmalonyl CoA to succinyl coenzyme A

The conversion of methylmalonyl CoA to succinyl coenzyme A is essential in metabolizing fatty acids and proteins for energy. Fats and proteins are broken down to produce methylmalonyl CoA, which is then converted to succinyl-CoA, which enters the citric acid cycle. This important cycle is found in the mitochondria and is used to produce energy for the cell. 

Helps Stabilize Mood 

SAM-e (S-adenosyl methionine) is made with the help of both vitamin B12 and folic acid. SAM donates methyl groups, which are essential for healthy brain function. Homocysteine is converted to methionine, which is used to form SAM. Vitamin B12 deficiency slows this conversion, resulting in increased homocysteine. Increased homocysteine is a marker for vitamin B12 and folate deficiency. 

Homocysteine levels are increased in people with depression. Based on the results of clinical trials, researchers suggested that taking supplements of folic acid and vitamin B12 could help improve depressive symptoms (Coppen, 2005). 

Vitamin B12 is also involved in producing serotonin, a chemical messenger in the brain that modulates mood. More research is needed to understand the relationship between vitamin B12, serotonin, and mood (Almeida, 2015).

why Vitamin B12 benefits are important

May Improve Cognitive Function

Elevated homocysteine levels are associated with an increased incidence of Alzheimer’s disease and dementia. High homocysteine levels may reduce blood flow and oxygen to brain cells, increase protein tangles in the brain, and inhibit methylation reactions. But it is not clear if restoring healthy levels of vitamin B12 with a supplement can improve cognitive function because the research studies that are available are not well-designed (Smith, 2016). 

A systematic review of 43 clinical trials found that low vitamin B12 levels are associated with cognitive impairment and dementia, and a small subset of these are reversible with vitamin B12 replacement. Researchers found that vitamin B12 supplementation did not improve cognition in people with healthy B12 levels (Moore, 2012). 

Scientists use several different kinds of studies. The ideal study is a randomized, controlled clinical trial. Unfortunately, these kinds of studies cannot be used to investigate the effects of vitamin B12 deficiency because researchers would need to make some people vitamin B12 deficient and then see the effects on their health. So instead, researchers observe the effect of vitamin B12 deficiency on people who are already diagnosed with low B12. Observational studies are viewed critically because they are open to bias and statistical interpretation. 

May Reduce Cancer Risk

Researchers do not fully understand the relationship between vitamin B12 levels and cancer risk. Some studies show an increased risk of cancer with vitamin B12 deficiency, especially for stomach cancer (Miranti 2017), but this is not consistent across all studies, and some even showed opposite results (NIH 2022). 

May Reduce Pain

Vitamin B12 is essential for proper nerve function. A lack of vitamin B12 can cause paresthesias and nerve pain. Paresthesias are tingling or pins-and-needles sensations in the fingers and toes. Restoring vitamin B12 levels may help reduce pain and these uncomfortable sensations. 

May Boost Metabolism

Vitamin B12 is involved in converting the energy stored in food into a form your body cells can use. In an extensive study, researchers in the US found an inverse relationship between vitamin B12 deficiency and obesity. Further research will be needed to determine whether this is a causative relationship or if other factors contribute to it (Sun 2019, Boachie 2020).

7 Reasons Why Vitamin B12 Is Important

Which Foods Are Highest in Vitamin B12?

Only bacteria can produce vitamin B12. It is found in animal products such as meat, poultry, fish, dairy, and eggs. According to a US national survey, the average dietary intake of vitamin B12 is 5.4 μg/day for adult men and 3.4 μg/day for adult women (Dror 2012).

Foods high in vitamin B12 include:

  • Organ meats
  • Clams
  • Sardines
  • Crab
  • Mackerel
  • Beef
  • Fortified cereals
  • Nutritional yeast

Are There Any Health Risks from Excessive Vitamin B12?

According to the National Institutes of Health, the Food and Nutrition Board (FNB) did not establish an upper limit for vitamin B12 because it has low toxicity and is considered safe, even at large doses (NIH 2022).

Restoring your vitamin B12 levels to a healthy range has many health advantages. If you have a health condition, dietary needs, or are taking a medication that is associated with low vitamin B12, talk to your healthcare provider about your symptoms to learn whether vitamin B12 deficiency may be the cause.

Conclusion to Why Vitamin B12 is Important

Recognizing the pivotal role Vitamin B12 plays in maintaining energy levels, heart health, mood stabilization, cognitive function, cancer risk reduction, pain alleviation, and metabolism enhancement underscores its importance in our daily lives. For those looking to buy Vitamin B12, especially in light of its numerous health benefits, exploring quality supplementation options becomes essential. To learn more about how Vitamin B12 can support your health and well-being, consider visiting Invigor Medical for comprehensive insights and options.

Frequently Asked Questions

What happens when your vitamin B12 is low?

When your vitamin B12 levels are low, it can lead to various health issues, including fatigue, weakness, constipation, loss of appetite, weight loss, and poor memory. Additionally, some may experience megaloblastic anemia, which makes people tired and weak. In more severe cases, low B12 levels can cause nerve problems like numbness and tingling in the hands and feet, balance issues, depression, confusion, dementia, and poor memory.

What is the main benefit of vitamin B12?

The main benefit of vitamin B12 is its critical role in red blood cell formation, cell metabolism, nerve function, and the production of DNA, the material in all cells. By supporting the normal function of nerve cells, B12 helps with the synthesis of neurotransmitters responsible for regulating mood and brain functions, thus playing a vital role in maintaining energy levels and supporting overall mental and physical health.

What are the 5 major functions of vitamin B12?

Vitamin B12 is essential for various bodily functions. It supports red blood cell formation, neurological health, DNA synthesis, energy metabolism, and homocysteine regulation.

Should you take B12 everyday?

Regarding the frequency of taking B12 supplements, it depends on individual health needs, dietary intake, and advice from a healthcare professional. People who may benefit from taking B12 daily include those with a diagnosed deficiency, older adults, vegetarians and vegans, and individuals with certain health conditions that affect B12 absorption. Always consult with a healthcare provider to determine the appropriate dosage and frequency for your specific situation.

Author: Leann Poston, M.D.
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