Top 8 Causes of Vitamin B12 Deficiency

by DailyHealthPost Editorial

Today, we’ll look at the top causes of vitamin B12 deficiency (or cobalamin deficiency) – other than not eating enough Vitamin B12 rich foods or being vegan. Vitamin B12 is an essential nutrient that enables critical cellular functions, including the production of DNA. It’s also needed for myelin – which covers and protects nerves – as well as red blood cell formation! It’s no wonder then, that low levels of vitamin B12 can cause debilitating and dangerous side effects, including muscle fatigue, anemia, and neurologic conditions like numbness and tingling in hands or feet, anxiety, irritability, dementia and even hallucinations.

Top 8 Causes of B12 Deficiency

Before we get into the causes of vitamin B12 deficiency, you should know that the absorption of this nutrient is limited. When we eat food sources of vitamin B12 (example milk, cheese, eggs, and meats), the vitamin B12 must first be released from the proteins in the ingested food by the activity of hydrochloric acid, or stomach acid, and the digestive enzyme, pepsin. The “freed” vitamin B12 is combined with Intrinsic factor, a carrier protein produced by the parietal cells in the stomach lining, that transports B12 to the last part of the small intestine where it is absorbed.

In a healthy body, the absorption of vitamin B12 is 50 to 60 percent, because the capacity of intrinsic factor is limited. When oral doses of B12 exceed one or two micrograms at a time, the body’s ability to absorb B12 decreases. Therefore, to maintain optimal B12 levels, it is recommended to obtain multiple small doses through food, or one larger supplemental dose to account for limited absorption.


Next, let’s look at the sneaky culprits stealing your vitamin B12.

#8. Low Stomach Acid.

Since B12 absorption occurs in the stomach and requires stomach acid, if you don’t have enough hydrochloric acid, you can’t absorb enough B12, and this can lead to deficiency. Often, low stomach acid is marked by indigestion, gas, bloating, heartburn, and acid reflux. The normal pH level of hydrochloric acid in the stomach should be between 1 to 3. If you have low stomach acid, also called hypochlorhydria, the pH is usually between 3 to 5.

One common cause of low stomach acid is the use of antacids and proton pump inhibitors for indigestion, heartburn and acid reflux, based on the belief that the stomach is secreting too much acid. In reality, many acid-related issues are caused by low stomach acid. Other reasons that cause low stomach acid are chronic stress, aging, and consumption of processed foods and refined sugars. To boost your stomach acid level and reduce symptoms, try taking one tablespoon of apple cider vinegar mixed in very little water before a meal. Make sure you watch till Number 1, as this cause of vitamin B12 deficiency will come as a real surprise.

#7. Lack of Intrinsic Factor.

As we age, our bodies tend to produce less intrinsic factor, and in some cases, even produce antibodies that destroy the parietal cells, resulting in low levels of Vitamin B12. A serious form of Vitamin B12 deficiency affecting 2% of people over 60, is pernicious anemia — a condition that can cause a very low red blood cell count, weakness, and fatigue. However, up to 50 percent of anemia from B12 deficiency in adults is caused by pernicious anemia.

One cause of pernicious anemia is atrophic gastritis. This condition happens when a person’s stomach lining becomes inflamed over an extended period, and the body mistakenly attacks healthy cells including intrinsic factor – which leads to a loss or lack in key nutrients such as iron, vitamin B12 and folate. In rare cases, some people have inherited pernicious anemia; they are born without the ability to make enough intrinsic factor. Fortunately, pernicious anemia responds well to treatment with high-dose vitamin B12, through oral supplements or injections.

#6. Gastrointestinal Issues.

Disturbances in the digestive tract like colitis, Crohn’s disease, inflammatory bowel disease, leaky gut syndrome, and celiac disease can impair absorption of nutrients and decrease your B12 levels. Watch our video, “Top 8 Foods Causing Leaky Gut and Leaky Brain“.

#5. Gastric Bypass Surgery.

A gastric bypass is a weight loss surgery to make the stomach smaller and change the connection between the stomach and the intestines. Vitamin B12 deficiency occurs in 40 to 70% of patients after a gastric bypass. This is because the stomach is 80 to 90% smaller after bypass and produce a lot less stomach acid. Additionally, the first part of the small intestine called the duodenum is bypassed; this is where “vitamin B12” combines with intrinsic factor. As a result, very little B12 make it down the small intestine to the ileum to be absorbed.


#4. Metformin Usage.

Long-term usage of Metformin can cause vitamin B12 deficiency, according to a study published in the Journal of Clinical Endocrinology and Metabolism. Metformin was developed to treat Type 2 diabetes, but is also used for women suffering from PCOS, and as a weight loss aid. Interestingly, other studies have linked B12 deficiency to insulin resistance, which can lead to high blood sugar levels, Type 2 diabetes, and weight problems.

#3. Too Much Alcohol.

When you drink too much alcohol, your body uses up a lot of nutrients including B vitamins to process it, which can cause B12 deficiency unless you’re getting a lot of B12 through food and supplements. Other than causing damage to your liver over time, alcohol overconsumption also causes inflammation in your stomach lining, which lowers stomach acid production. The solution is to simply stick to 1 to 2 drinks a day.

#2. Taking Birth Control.

Taking the pill may come with the inconvenient side effect of depleting your body’s B vitamin stores — especially folate, riboflavin, vitamin B6, and B12. Research has shown that birth control pills with higher estrogen levels are more likely to cause vitamin B12 deficiency, although actual deficiency seems to be uncommon. Still, women taking birth control should also take a good quality B complex supplement with plenty of B12.

#1. Intestinal Parasites.

Intestinal parasites like tapeworms or giardia “hijack” the incoming vitamin B12 inside the small intestine for their own nutrition, and thus prevent B12 from reaching your bloodstream. One way a person can get infected by tapeworms is eating under-cooked or raw fish. If you develop gastrointestinal issues like stomach pain, diarrhea, sudden weight loss, excess bloat or gas that cannot be explained, it’s time to see your doctor.

Fortunately, vitamin B12 deficiency is an easy condition to prevent and treat.

To boost vitamin B12 levels, choose a high-absorption, naturally-occurring methylcobalamin supplement like the one recommended below, or eat more B12 rich foods. For omnivorous people, the order of B12 content per serving, from highest to lowest, is: mussels, clams, fish (tuna, trout and salmon are highest), beef, milk, yogurt, cheese, eggs, and chicken. Plant-sourced foods fortified with vitamin B12 are nondairy milks (such as soy, almond, and oat milk), breakfast cereals with no sugar and high fiber, and nutritional yeast.

Watch our previous video, “Top 11 Vitamin B12 Deficiency Symptoms” which covers vitamin B12 in depth. If you enjoyed this video, Like, Share, and Subscribe, and Click on the Bell icon, so you never miss a video! And now over to you! Are you experiencing symptoms of vitamin B12 deficiency? If so, what is your cause of B12 deficiency? Leave your comment below. We’d love to hear from you! To get daily health tips for optimizing your nutrition and lifestyle, so you can feel amazing naturally, join our FREE email newsletter by clicking the link below. And be sure to check out our other videos!