Vitamin B12 Deficiency: Causes, Symptoms, and How to Prevent It

What are the Common Causes of Vitamin B12 Deficiency?

Causes of Vitamin B12 Deficiency

Dietary Deficiency

Vitamin B12 is predominantly found in animal-derived foods like meat, eggs, and dairy^[1]. Those who follow vegetarian or vegan diets, since they don’t consume enough of these foods, risk deficiency. Without B12 supplements or fortified foods, they may not meet the body’s needs.

Phil Ross, M.S. CPT

According to Phil Ross, M.S., CPT, athletes on restrictive diets often face deficiencies due to insufficient intake of nutrients from animal products. He recommends a B12 supplement in the form of methylcobalamin, which is highly bioavailable, combined with folate-rich foods or a custom B9 supplement as part of a comprehensive recovery plan.

Additionally, malabsorption issues within the digestive system can further exacerbate this deficiency. So, you might want to keep an eye on your B12 levels and consider dietary adjustments if you’re on plant-based diets.

Pernicious Anemia

Pernicious anemia is an autoimmune condition that significantly impacts Vitamin B12 absorption^[2]. In this disorder, the immune system mistakenly attacks the stomach cells responsible for producing intrinsic factor, a protein essential for B12 absorption in the small intestine^[3].

Without intrinsic factor, even a diet rich in Vitamin B12 cannot prevent deficiency, as the body becomes unable to properly absorb the nutrient.

Medications

Certain medications can interfere with the absorption of Vitamin B12. Antacids and proton pump inhibitors (PPIs), often used to treat heartburn and acid reflux, reduce the stomach acid necessary to release B12 from food. A 2018 study notes;

A lack of gastric acid, due to PPI or H2RA use (or pathophysiologic conditions that affect gastric acid production, such as atrophic gastritis), will reduce the digestive capacity to release vitamin B-12 from foods, and thus reduce the amount of vitamin B-12 that is absorbed in the body^[4]. - Joshua W Miller.

Metformin, a widely prescribed medication for diabetes, also poses a risk by affecting B12 absorption. A 2023 study admits;

Metformin can cause vitamin B12 deficiency by reducing the absorption of the IF complex through the enteral cubilin receptor in the terminal ileum…^[5] - Ehsan Sayedali, et al.

Those on these medications may need to monitor their B12 levels closely and consider supplementation if necessary.

Aging

As people age, their bodies naturally produce less stomach acid and intrinsic factor, both of which are crucial for Vitamin B12 absorption. This decline makes older adults more susceptible to deficiency.

As a preventive measure, the elderly should monitor their B12 status and adjust their diets or take supplements as needed to maintain adequate levels of this vital nutrient.

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What Could be the Risk Factors for B12 Deficiency?

Here are the key factors that increase the risk of developing this deficiency:

• Age-Related Decline in B12 Absorption: Older adults are more susceptible to vitamin B12 deficiency symptoms, which can include fatigue, weakness, and memory issues.
• Certain Medical Conditions: Medical conditions like Crohn's disease and celiac disease can significantly affect nutrient absorption in the gastrointestinal tract, leading to Vitamin B12 deficiency^[6]. These conditions cause inflammation and damage to the intestines, hindering the body's ability to absorb B12. The B12 deficiency neurological symptoms, such as numbness and tingling in the limbs, often accompany these diseases.
• History of Gastric Bypass Surgery: Gastric bypass and other weight-loss surgeries can alter the digestive system significantly, impacting how nutrients, including Vitamin B12, are absorbed.

  Post-surgery, patients often experience a decrease in stomach acid production and intrinsic factor, leading to deficiency.

• Strict Vegetarian or Vegan Diets: Those following strict vegetarian or vegan diets may not consume adequate amounts of Vitamin B12, as it is primarily found in animal products. Without sufficient intake or supplementation, these diets can lead to deficiency.

• ✅ Over 50 years old
• ✅ Vegan/Vegetarian
• ✅ On Metformin or PPIs
• ✅ Had Gastric Bypass

Read Also: What Is Vitamin B12 Good For

Symptoms of B12 Deficiency

• Fatigue and weakness occur when low Vitamin B12 levels reduce healthy red blood cells, limiting oxygen transport and causing early deficiency symptoms.
• Anemia caused by B12 deficiency can result in pale or jaundiced skin, as reduced red blood cell production affects the skin's appearance.
• Anemia from B12 deficiency leads to shortness of breath, especially during physical activity, as the body struggles to deliver adequate oxygen.
• Neurological symptoms like tingling, numbness, and muscle weakness result from nerve damage caused by untreated Vitamin B12 deficiency and need immediate care.
• Mental health issues such as anxiety, depression, or memory problems often arise from B12 deficiency, impacting emotional well-being and cognitive function.
• Digestive problems like nausea and constipation may develop with Vitamin B12 deficiency, disrupting nutrient absorption and affecting gastrointestinal health.

How Does Deficiency of Vitamin B12 can Affect Hair, Skin, and Nails?

Deficiency of Vitamin B12 may affect hair, skin, and nails in many ways:

• Skin Health: B12 deficiency can result in hyperpigmentation, vitiligo, mouth ulcers, or eczema-like symptoms.
• Hair Growth: With the deficiency of B12, loss and thinning of hair may occur because of inadequate nutrition of hair follicles.
• Nail Appearance: Low B12 levels may lead to blue or brown-grey nails, which heal after fixing the B12 levels.
• Balance is Key: Both insufficient and excessive B12 can cause skin changes, so proper levels are crucial for overall health.

How Is Vitamin B12 Deficiency Diagnosed?

Vitamin B12 deficiency is identified through key tests that help determine its severity and guide treatment. Here's a breakdown:

• 1. Blood Test: A simple blood test measures B12 levels and can detect anemia or nerve-related issues linked to deficiency ^[7].
• 2. Stages of Deficiency: Tests identify the 4 deficiency stages, helping assess severity and treatment needs.
• 3. Additional Testing: Doctors may evaluate nerve damage or anemia to uncover symptoms like numbness and tingling early on.

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You need to understand the full scope of what causes vitamin B12 deficiency in males and females, and recognize how long to recover from vitamin B12 deficiency might take. While these tests do not directly indicate if vitamin B12 deficiency can be a sign of cancer, they help rule out other potential causes and ensure a comprehensive treatment plan.

Also Read: How Vitamin B12 Supports Nerve and Brain Health

Did You Know?

How Can You Prevent B12 Deficiency?

How to Get Vitamin B12

• Dietary Sources: eat lots of meat, fish, poultry, eggs, and dairy. These foods provide ample amounts of B12 and help mitigate vitamin B12 deficiency symptoms.
• Fortified Foods: Opt for cereals and plant-based supplements. Milk fortified with B12, especially if you follow a vegetarian or vegan diet. These options help address vitamin B12 deficiency and support nutrient intake.

• B12 Supplements: Consider Vitamin B12 supplements you're at risk, like older adults or those with gut issues, supplements can help speed up vitamin B12 deficiency recovery.

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When to Take Vitamin B12 Supplements

If you are using Vitamin B12 supplements, it’s generally fine to take Vitamin B12 on an empty stomach. However, some individuals may experience mild stomach discomfort when taking B12 without food. If this occurs, consider taking the supplement with a small meal to minimize any potential discomfort.

Related - How Much Vitamin B12 Should I Take?