Why vitamin B12 is so important after bariatric surgery

Have you ever wondered why vitamin B12 is so important after bariatric surgery? Vitamin B12, or cobalamin (a water-soluble vitamin), plays several vital roles in the body. It is naturally found in animal products and can be obtained through fortified foods and supplements. However, many people do not absorb vitamin B12 properly due to multiple factors, such as medications, disease, genetics, or dietary choices. This can result in vitamin B12 deficiency.

Bariatric surgery patients are especially prone to developing vitamin B12 deficiency since surgery alters the stomach and intestines, which are crucial to vitamin absorption. Therefore, bariatric patients must regularly monitor their vitamin B12 levels and supplement accordingly to prevent complications and optimize their health outcomes.

Here, we will examine how Vitamin B12 plays a crucial role in bariatric surgery patients’ lives, how to monitor and manage its levels, and more in this article. Let’s dive in!

How is vitamin B12 absorbed?

A complex process is involved in the absorption of vitamin B12. First, vitamin B12 in food is freed from food in the stomach by stomach acid and pepsin. Then, B12 binds to an R-binder or transcobalamin I protein secreted by the salivary glands and the stomach.

As this complex travels to the small intestine, pancreatic enzymes break down the R-binder and release vitamin B12 again. Next, it binds to another protein called intrinsic factor, which the stomach cells produce. As soon as this complex enters the small intestine, it is absorbed by specialized cells in the ileum. Finally, the absorbed vitamin B12 binds to another protein called transcobalamin II, which transports it to the bloodstream and delivers it to various tissues and organs.

What can interfere with vitamin B12 absorption?

Several factors can impair or reduce vitamin B12 absorption, including:

Medication:

Certain drugs can affect the production or function of stomach acid, intrinsic factor, or pancreatic enzymes, all necessary for absorbing vitamin B12. These include metformin (a diabetes medication), proton pump inhibitors (PPIs) and H2 blockers (acid reflux medication), birth control pills (oral contraceptives), antibiotics (such as chloramphenicol), and anticonvulsants (such as phenytoin).

Disease:

Some conditions can damage or inflame the stomach or intestinal lining. As a result, it reduces intrinsic factor secretion or absorption of vitamin B12. These include chronic gastritis (stomach inflammation), celiac disease (gluten intolerance), Crohn’s disease (intestinal inflammation), and atrophic gastritis or pernicious anemia (autoimmune disorders that destroy stomach cells).

Diet:

Vegetarians and vegans may not consume enough vitamin B12 from animal sources and may need supplements or fortified foods. However, some fortified foods may contain synthetic forms of vitamin B12 that some people do not absorb well.

Moreover, excessive intake of folic acid from fortified foods or supplements can mask the symptoms of vitamin B12 deficiency by correcting the anemia but not the nerve damage.

Age:

As people age, they may produce less stomach acid or intrinsic factor, impairing vitamin B12 absorption. The reduced appetite or dentition problems of older adults may also lead to a lower intake of vitamin B12.

Genetics:

Various genetic variants can affect a person’s ability to metabolize or transport vitamin B12. For example, people with mutations in genes that code for transcobalamin II or its receptor may have lower levels of circulating vitamin B12.

How can bariatric surgery affect vitamin B12 absorption?

Bariatric surgery helps people lose weight by reducing their food intake and/or calorie and nutrient absorption. However, this can also affect their absorption of vitamin B12 in several ways:

Reduced stomach acid after bariatric surgery:

Most types of bariatric surgery reduce stomach acid production by removing or bypassing parts of the stomach. This can impair the release of vitamin B12 from food proteins and decrease its availability for binding to R-binder or intrinsic factor.

Reduced intrinsic factor after bariatric surgery:

Some types of bariatric surgery remove or bypass parts of the stomach that produce intrinsic factor. As a result, less intrinsic factor is available for binding to vitamin B12 and transporting it to the ileum for absorption.

Reduced ileal surface after bariatric surgery:

Some types of bariatric surgery bypass parts of the small intestine, including the ileum. This can reduce the surface area for absorbing vitamin B12 and the intrinsic factor complex.

Reduced pancreatic enzymes after bariatric surgery:

Certain types of bariatric surgery bypass parts of the small intestine that receive pancreatic enzymes. This can impair the breakdown of the R-binder and the release of vitamin B12 for binding to intrinsic factor.

How can vitamin B12 deficiency be diagnosed after bariatric surgery?

Vitamin B12 deficiency can be diagnosed by measuring blood levels of vitamin B12 and other related markers. The most common test is the serum vitamin B12 test, which measures the blood’s total amount of vitamin B12.

However, this test may not be accurate or sensitive enough to detect mild or early deficiency, as it does not reflect the amount of active or available vitamin B12 in the tissues. Therefore, other tests may be needed to confirm the diagnosis, such as:

Methylmalonic acid (MMA) test:

This test measures MMA, a byproduct of a metabolic process that requires vitamin B12 as a cofactor. The body accumulates MMA when vitamin B12 levels are low. Therefore, high levels of MMA indicate vitamin B12 deficiency.

Homocysteine test:

The homocysteine test measures the amount of homocysteine, an amino acid that participates in a metabolic pathway requiring vitamin B12 and folate. Homocysteine accumulates in the blood when vitamin B12 or folate levels are low. Therefore, high levels of homocysteine indicate vitamin B12 or folate deficiency.

Holotranscobalamin (holoTC) test:

This test measures the level of holoTC, which is the active form of vitamin B12 bound to transcobalamin II and delivered to the tissues. As a result, low levels of holoTC indicate vitamin B12 deficiency.

Why is vitamin B12 essential after bariatric surgery?

Vitamin B12 is important for everyone, especially bariatric surgery patients, as it is vital in many aspects of their health and well-being. Some of the benefits of vitamin B12 are:

Prevents anemia:

Research has shown that Vitamin B12 is crucial for the production of red blood cells, which transport oxygen throughout the body. The lack of vitamin B12 can lead to megaloblastic anemia, which is characterized by large and immature red blood cells that cannot function properly. The condition can result in fatigue, weakness, shortness of breath, pale skin, and increased heart rate.

Supports nerve function:

Additionally, studies have shown that it is essential for maintaining the myelin sheath, which protects nerve fibers and facilitates signal transmission. Low levels of vitamin B12 can damage the myelin sheath and cause nerve problems, such as tingling, numbness, burning, pain, or even more severe conditions, such as peripheral neuropathy or spinal cord degeneration.

Enhances cognitive function:

Studies have shown that Vitamin B12 is vital in cognitive function enhancement. It synthesizes neurotransmitters, such as serotonin and dopamine, which regulate mood, memory, and learning. Low levels of vitamin B12 can impair cognitive function and cause symptoms such as depression, confusion, dementia, or Alzheimer’s disease.

Protects cardiovascular health:

The vitamin B12 helps maintain cardiovascular health by regulating homocysteine levels. Folate and vitamin B12 work together to lower homocysteine levels, an amino acid that damages blood vessels and contributes to heart disease and stroke. In addition, a high level of homocysteine can inhibit the function of nitric oxide, a molecule that relaxes and dilates the blood vessels and improves blood flow.

Supports metabolism:

Vitamin B12 is a cofactor in many enzymes involved in energy production and fat metabolism. When vitamin B12 levels are low, carbs, fats, and proteins are not properly converted into energy, resulting in weight gain, low energy, and poor appetite.

DNA Synthesis:

During DNA synthesis, our cells produce new DNA molecules. It is essential for the division and growth of cells in our bodies.

Vitamin B12 facilitates DNA synthesis, ensuring our cells can replicate and grow properly. In simpler terms, vitamin B12 is like a helper that ensures our cells can make new DNA, which is necessary for our body to function and grow.

How much vitamin B12 do bariatric surgery patients need?

Vitamin B12 has a recommended dietary allowance (RDA) of 2.4 mcg daily for adults. However, bariatric surgery patients may need more than that to prevent deficiency and maintain optimal health. The exact amount may vary depending on the type of surgery, the individual’s absorption capacity, and blood levels.

Therefore, it is imperative to consult a healthcare professional who can monitor the individual’s vitamin B12 status and prescribe the right dosage and supplementation.

According to some guidelines, bariatric surgery patients may need to take the following:

After gastric banding or sleeve gastrectomy, 350-500 mcg of vitamin B12 per day is recommended
After gastric bypass or duodenal switch, take 500-1000 mcg of vitamin B12 per day
1000 mcg per month of intramuscular or subcutaneous vitamin B12 after any type of bariatric surgery

However, these recommendations are general and may not apply to everyone. Different people may require different dosages based on their needs and preferences. For this reason, it is crucial to follow the advice of a healthcare provider who can tailor the supplementation regimen to each patient’s specific needs.

Managing Vitamin B12 Deficiency After Bariatric Surgery

Bariatric surgery patients risk developing Vitamin B12 deficiency due to factors like chronic inflammation, celiac disease, a diet lacking in animal products, low stomach acid, H. pylori infection, and excessive folic acid intake (common in processed foods). Therefore, it’s imperative to manage this potential nutritional shortfall. Here’s how:

Supplementation:

Bariatric surgery patients often need vitamin B12 supplements to meet their nutritional needs. These supplements are available in various forms:

Sublingual tablets or lozenges:

These oral forms of vitamin B12 dissolve under the tongue and instantly get absorbed into the bloodstream through the mucous membranes. As opposed to regular oral tablets or capsules, they do not require stomach acid or intrinsic factor.

Nasal spray or gel:

These forms of vitamin B12 are spray or apply into the nose and absorb through the nasal lining into the bloodstream. They may also bypass the need for stomach acid or intrinsic factor and may be more convenient than oral forms.

Intramuscular or subcutaneous injections:

These forms of vitamin B12 are inject into the muscle or under the skin and absorb directly into the bloodstream. They are usually given once a month or as need and may be more effective than oral or nasal forms for severe deficiency.

Diet Modification:

Healthcare professionals may recommend dietary modifications to improve vitamin B12 intake. Among the best sources of vitamin B12 are meat, poultry, fish, eggs, dairy products, and organ meats. The fortification of plant-based products with vitamin B12 may also be present in cereals, breads, dairy products, soy milk, nutritional yeast, and vegan foods.

However, fortified foods do not always contain adequate levels or bioavailable forms of vitamin B12, so you should consult a health professional before relying on them. Here are some examples of foods that contain vitamin B12:

Clams: 3 ounces (85 grams) provide 84 micrograms (mcg) of vitamin B12

Beef liver: 3 ounces (85 grams) provides 70 mcg of vitamin B12

Trout: 3 ounces provide 5.4 mcg of vitamin B12

Salmon: 3 ounces provide 4.8 mcg of vitamin B12

Tuna: 3 ounces provides 2.5 mcg of vitamin B12

Fortified cereal: 1 cup (30 grams) supplies 6 mcg of vitamin B12

Milk: 1 cup (240 mL) provides 1.2 mcg of vitamin B12

Yogurt: 6 ounces (170 grams) supplies 1 mcg of vitamin B12

Cheese: 1 ounce (28 grams) provides 0.9 mcg of vitamin B12. The amount may vary depending on the type of cheese, with Swiss cheese being the highest and cottage cheese being the lowest.

Eggs: 1 large egg provides 0.6 mcg of vitamin B12

Chicken: 3 ounces (85 grams) provide 0.3 mcg of vitamin B12

Education and Support:

Patients should receive education and ongoing support regarding nutrition and supplementation from a qualified dietitian or nutritionist. Educating individuals about their dietary habits and supplement usage can help them make better-informed choices.

Conclusion

Bariatric surgery patients need vitamin B12 to ensure their health and well-being. Regular monitoring, supplementation, and attention to dietary choices ensure that bariatric surgery patients enjoy the full benefits of their transformation while safeguarding their nutritional needs. Also, remember Vitamin B12 is not just a supplement; it’s a lifeline to a healthier post-surgery life.