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  • Am I at risk of vitamin B12 deficiency after sleeve gastrectomy?
Czy grożą mi niedobory witaminy B12 po rękawowej resekcji żołądka?
Am I at risk of vitamin B12 deficiency after sleeve gastrectomy?
- | 5.11.2021 | 3 minutes
Vitamin B12 is the largest and most structurally complex vitamin. B12, otherwise known as cobalamin, is one of the most common vitamin deficiencies among bariatric surgery patients.

Vitamin B12 - what is it and why is it so important?

Vitamin B12 is an important nutrient that the human body needs to maintain healthy nerve cells and blood cells. The vitamin is also involved in the formation of DNA, the genetic material in cells. B12 also helps to prevent megaloblastic anaemia.


Absorption of vitamin B12

A glycoprotein secreted by the parietal cells of the gastric mucosa is responsible for the absorption of vitamin B12 in the intestine. A lack of production or use of the intrinsic factor glycoprotein in the human body can cause vitamin B12 deficiency. The part of the stomach that is responsible for the production of intrinsic factor is bypassed when gastric bypass surgery is performed or cut out in sleeve gastrectomy. This leads to a reduction in intrinsic factor and consequently a deficiency.


Vitamin B12 deficiency 

For the most part, vitamin B12 deficiency is due to the patient's inability to absorb the vitamin, rather than insufficiency due to diet. However, limiting the portion sizes consumed after bariatric surgery may contribute to deficiency. This is why supplementation is so important for all people after surgery.

What are the symptoms of vitamin B12 deficiency?

Some of the symptoms of vitamin B12 deficiency include:

Anemia and associated fatigue, shortness of breath, palpitations. Nerve conduction problems such as tingling and numbness:

  • Slower reflexes
  • Tongue ulcers
  • Visual disturbances

More serious symptoms of vitamin B12 deficiency include heart failure and permanent nerve damage.

Dietary requirements for vitamin B12 deficiency

For patients who have had bariatric surgery and are struggling with vitamin B12 deficiency, there are dietary recommendations that can help increase vitamin B12 levels in the body. Some of the best sources of vitamin B12 include animal products - meat, fish or seafood. For vegetarians, fermented foods - dairy, tempeh or fortified cereals - are rich sources of vitamin B12. 

If you have any questions about bariatric surgery or vitamin B12 deficiency, contact the Baria3 team.






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