Talk with your doctor before adding extra vitamin B12

Talk with your doctor before adding extra vitamin B12

Before purchasing vitamin B12 supplements, determine if you need them. They are often marketed as a solution for various issues, but assessing if they’re necessary for you is essential.

Brief historical overview of vitamin B12

Vitamin B12 was the last vitamin in the B complex family to be discovered in 1926. A condition associated with Vitamin B12, called pernicious anemia, is an autoimmune disorder when the intestines cannot properly absorb vitamin B12. It causes patients to become tired and weak, as the body cannot produce enough healthy red blood cells, which can be fatal. Abraham Lincoln’s wife, Mary Todd Lincoln, cause of death is believed linked to having pernicious anemia long before its discovery. In the same year B12 was discovered, famous markswoman Annie Oakley also died from pernicious anemia due to the body’s inability to absorb B12 from the intestine. Only years later, scientists figured out how to treat pernicious anemia with B12 injections.

Individuals with B12 deficiency (excluding pernicious anemia) can typically increase their B12 intake through a diet rich in B12.

What makes vitamin B12 an essential nutrient?

Vitamin B12, or cobalamin, is an essential B vitamin that your body cannot produce alone. It is necessary to obtain this nutrient from food sources that contain it. Vitamin B12 is essential in maintaining healthy brain and nerve function, aids in making DNA and red blood cells, and helps reduce homocysteine levels. High levels of homocysteine are linked to various chronic conditions such as dementia, heart disease, stroke, and osteoporosis.

Animal-based foods are the only food source of Vitamin B12. Therefore, it is imperative to eat animal-based foods to prevent a vitamin B12 deficiency. These sources include beef, poultry, fish, pork, eggs, cheese, yogurt, and milk. Plant-based alternative sources have been fortified with vitamin B12, which includes fortified cereals and plant-based dairy alternatives like soy, almond, or rice milk. 

To absorb and digest vitamin B12, it must first be released from its food source. This is aided by stomach acids that bind to intrinsic factor, a protein cells produce in the stomach lining.

Causes of a vitamin B12 deficiency

As we age, the risk of developing a deficiency in vitamin B12 increases. This can happen for various reasons, but one of the main causes is growing older. Studies show that approximately 3.2% of individuals over 50 have very low levels of B12, while up to 20% may have borderline deficiency. Aging reduces the production of stomach acid, leading to decreased intrinsic factor production. This makes it more challenging to extract B12 from food. Those who cannot produce enough intrinsic factor and, therefore, cannot absorb B12 from the intestine may develop pernicious anemia.

Other causes of vitamin B12 deficiency:

  • Individuals who follow a vegan diet devoid of animal-based foods

  • Weight loss surgery

  • Crohn’s or celiac disease that attacks the stomach lining or gastrointestinal lining

  • Taking heartburn medications such as proton-pump inhibitors or Metformin may interfere with B12 absorption as they suppress stomach acid needed for food to release B12.

Signs of a B12 deficiency:

  • Difficulty with balance
  • Feeling depressed
  • Excessvie fatigue
  • Muscle weakness
  • Memory loss or confusion
  • Numbness or tingling in hands or legs brought on by nerve damage
  • Anemia

Checking for a vitamin B12 deficiency

It’s uncommon for individuals with a balanced diet with animal products to have a vitamin B12 deficiency. However, if you’re 65 years or older or experiencing symptoms that suggest a possible shortage of B12, a straightforward blood test can determine the status of your levels. Doctors may automatically test their patient’s vitamin B12 levels at age 65 and every three to four years. The blood test will search for markers of anemia, low B12 levels, and high levels of homocysteine and methylmalonic acid (MMA) to assess whether or not there is a deficiency.

A typical range for vitamin B12 levels in the bloodstream is 190 to 950 picograms per milliliter (pg/mL). If a test result falls between 200 to 300 pg/mL, it is considered borderline. Any number below 200 pg/mL is considered low. 

Effective treatment options exist for vitamin B12 deficiency

Treatment recommendations vary and depend on the cause of low vitamin B12 levels.

If you have a B12 deficiency caused by not consuming enough animal products or taking too many heartburn medications, you might be instructed to increase your intake of B12-rich foods. Another recommendation could be to take a 1,000 micrograms daily over-the-counter B12 supplement if your B12 levels are borderline low or your MMA levels are borderline high. Once your levels return to normal, you can decrease or stop taking the supplement.

It is recommended to take methylcobalamin, the natural form of B12 supplement, instead of cyanocobalamin, the synthetic form, as the latter may impair kidney function.

If you have pernicious anemia, B12 injections may be necessary as B12 supplements may not be effective for treating your B12 deficiency.

Before considering taking a B12 supplement, discussing any concerns with a doctor is important. These supplements are often affordable and can help prevent a deficiency if an individual does not consume animal-based foods regularly or follows a vegan diet.


Dr. David Samadi is the Director of Men’s Health and Urologic Oncology at St. Francis Hospital in Long Island. He’s a renowned and highly successful board certified Urologic Oncologist Expert and Robotic Surgeon in New York City, regarded as one of the leading prostate surgeons in the U.S., with a vast expertise in prostate cancer treatment and Robotic-Assisted Laparoscopic Prostatectomy.  Dr. Samadi is a medical contributor to NewsMax TV and is also the author of The Ultimate MANual, Dr. Samadi’s Guide to Men’s Health and Wellness, available online both on Amazon and Barnes & Noble. Visit Dr. Samadi’s websites at robotic oncology and prostate cancer 911. 




Talk with your doctor before adding extra vitamin B12
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