What are the causes of vitamin B12 deficiency

Written By The HealthMeth Team - Updated On Thursday, January 21, 2021 3:00 PM

Vitamin B12

Vitamin B12 is one of the vitamins dissolved in water, it is also called cobalamin, and it is an essential vitamin. That is, the body needs its presence in order to properly perform its functions, such as: nerve functions, the formation of red blood cells, and the process of producing chromosomal DNA, which is called short, and the metabolism of every cell in the human body depends on vitamin B12 This is because of its role in manufacturing fatty acids and producing energy by helping the body to absorb folic acid . [1] [2] [3]


To read more about the benefits of vitamin B12 visit the Vitamin B12 benefits article .


Causes of vitamin B12 deficiency

The following are the most important causes of vitamin B12 deficiency: [4] [5]

  • Not eating enough quantities of it: this usually occurs in vegetarians; As the presence of this vitamin is limited to animal foods, and lactating women who follow a vegetarian diet, their infants may suffer from a deficiency in this vitamin between the fourth and sixth months of their life. Because stores of vitamin B12 in the liver of these children are limited, and insufficient to cover their body's need for the process of growth and development.
  • The presence of an imbalance in its absorption in the body: This reason is the most common cause of vitamin B12 deficiency, especially in the elderly, and its absorption in the body decreases for several reasons, including:
    • A deficiency in the secretion of stomach acid, as it is important in the process of absorbing vitamin B12, which is found in food, but it does not affect the process of absorption of vitamin B12 in the form found in nutritional supplements.
    • Infection with some types of bacterial or parasitic infections, such as: Blind loop syndrome; It is a disease that occurs when part of the small intestine forms a loop that food overrides during the digestive process, which leads to food not moving normally in the digestive system, and the increase in bacterial reproduction in it, and fish tapeworm or what is called fish tapeworm, which is an infection of Flatworms infect humans when eating raw or undercooked fish; As bacteria and parasites in these cases feed on vitamin B12, the quantities available for absorption into the body are reduced.
    • Damage or abnormalities of absorption in the ileum; It is the part of the intestine where vitamin B12 is absorbed, and this damage may be caused by irritable bowel syndrome, or it may be removed by surgery.
    • The inability of the body to produce or use the intrinsic factor, and the intrinsic factor is defined as a protein excreted by parietal cells in the stomach, and this protein plays an important role in the absorption of vitamin B12 in humans. It is associated with vitamin B12 to enable the body to absorb it in the duodenum region of the intestine, and therefore the absence of the intrinsic factor leads to the body's inability to absorb vitamin B12, which causes its deficiency.
    • The use of some medicines, such as: antacids , and metformin ; It is a blood sugar lowering drug, and repeated exposure to nitrous oxide, or what is known as laughing gas.
    • Some uncommon medical conditions, such as: chronic pancreatitis, stomach surgeries or obesity surgery, malabsorption syndrome, acquired immunodeficiency syndrome or what is known as AIDS, and Imerslund-Graesbeck syndrome; It is a genetic disease that leads to ileal malabsorption.
  • An imbalance in the utilization of vitamin B12 in the body: This may be due to a deficiency of enzymes, some liver disorders , or problems with transporting proteins.


People at risk of vitamin B12 deficiency

The risk of developing vitamin B12 deficiency increases in certain groups of people, including the following: [6]

  • People aged 50 years or over.
  • People who follow a vegetarian diet , or vegetarian diet Pure .
  • People who have undergone gastrointestinal surgeries, such as weight loss surgery.
  • Some people with digestive problems, such as wheat allergy (Celiac Disease) and Crohn disease .


Symptoms of vitamin B12 deficiency

Symptoms of vitamin B12 deficiency can appear years after suffering a deficiency, and it is worth noting that the low level of this vitamin causes a decrease in the level of folate as well, and therefore the solution to the problem of low folate level and its return to a normal level may lead to masking the deficiency of vitamin B12, which makes it difficult to discover. [7] Also, a mild deficiency in this vitamin may not cause any symptoms, but severe deficiencies may lead to anemia , and the following are the most important symptoms that people with vitamin B12 deficiency feel: [8]

  • Weakness, fatigue, and feeling dizzy.
  • Heart palpitations, shortness of breath.
  • Pale skin color.
  • Smooth tongue.
  • Constipation, diarrhea, loss of appetite and gas.
  • Nerve problems, such as: numbness or tingling, muscle weakness, and trouble walking.
  • Vision loss.
  • Mental problems, such as: memory loss, depression , and behavioral changes.

For more information about the symptoms of vitamin B12 deficiency, you can refer to the article What are the symptoms of vitamin B12 deficiency .


Sources of vitamin B12

Vitamin B12 is found mainly in animal foods, especially meat and dairy products, and foods fortified with this vitamin can be a good source for vegetarians, and among the most important sources of vitamin B12 are the following: [9]

  • Animal liver and kidneys: The meat of animal organs is a rich source of vitamin B12, and the liver and kidneys of lamb in particular are among the richest in it. As 100 grams of lamb liver contains up to 1500% of the daily recommended amount of vitamin B12, and it also contains many minerals and vitamins, such as: selenium, copper, vitamin A , and vitamin B2, and it is also worth noting that 100 grams of Beef liver or calf provides 990% of the daily recommended amount of vitamin B12.
  • Shellfish Almlzimai: It is an oyster Almlzimai of psoriasis fish, which belong to molluscs, and containing 20 tablets small of the oysters on the ratio of 3300% of the recommended amount every day of vitamin B - 12, it should be noted that the broth clams high Almlzimai boiled Also, vitamin B12, as 100 grams of canned broth provides between 2.7 and 14.1 micrograms of this vitamin.
  • Sardines: 150 grams of refined sardine contains more than double the daily dietary reference amount of vitamin B12, and it should be noted that sardine is rich in omega-3 fatty acids . Which provides many health benefits to the body; It improves heart health and reduces inflammation.
  • Beef: 100 grams of beef contains 6.2 micrograms of vitamin B12, which is equivalent to 102% of the daily recommended amount of it, and beef also contains many other nutrients, such as: zinc, magnesium, and vitamin B2, Vitamin B3 and Vitamin B6.
  • Fortified cereal crops: They are a good source of synthetic vitamin B12, and are not derived from animal sources, so they are suitable for vegetarians, and it should be noted that it is advised to choose the type of fortified cereals rich in fiber , or whole grains, and low with added sugar.
  • Tuna: The thickness of tuna is a rich source of vitamin B - 12, providing 100 g quantity of fresh tuna ratio of 160% of the recommended amount every day of vitamin B12, while 165 grams of tuna packed in water contains 85% of the recommended amount every day of this vitamin , Tuna also contains many other nutrients, such as: lean protein, phosphorous, selenium, vitamin B3, and vitamin A.
  • Fortified nutritional yeast: It is one of the types of yeast made for food and not as a leavening agent for bread, and when fortified with vitamin B12, the manufacturer becomes a suitable source for vegetarians Whereas, two tablespoons of this fortified nutritional yeast; That is equivalent to 16 grams, provides 130% of the daily recommended amount of vitamin B12.
  • Trout: It is a trout of fish that live in fresh water, which is a rich source of nutrients, such as protein, healthy fats, minerals Calcellenium, phosphorus, manganese, and vitamin B 12; As 100 grams of this fish provides 125% of the daily recommended amount of this vitamin.
  • Salmon: Salmon is known for its high content of omega-3 fatty acid and B vitamins, as half of a slice of cooked salmon, or the equivalent of 178 grams, contains 80% of the daily recommended amount of vitamin B12.
  • Fortified plant-based milk: It is milk made from plant sources that do not naturally contain vitamin B12, and therefore it is fortified with the form it is made of, such as: soy milk , almond milk, and rice milk, and these types of milk are a good source for use by vegetarians; Whereas, one cup of soy milk, for example, contains up to 45% of the daily recommended amount of vitamin B12.
  • Milk and milk products: Milk and milk products are known to be a rich source of Vitamin B12. As one cup of whole milk contains 18% of the daily recommended amount of vitamin B12, and it is worth noting that Swiss cheese is the highest cheese with this vitamin; As 30 grams of this cheese provides about 16% of the daily recommended amount of vitamin B12.
  • Eggs: Two large eggs, or the equivalent of 100 grams of eggs, contain 22% of the daily recommended amount of vitamin B12, and eggs are also rich in vitamin D and vitamin B2 .


The recommended amount of vitamin B12

The following table shows the recommended daily amount of vitamin B12 for different age groups: [10]

Age group Amount (μg)
Infants from 0 to 6 months 0.4
Children from 7 to 12 months 0.5
Children from 1 to 3 years old 0.9
Children from 4 to 8 years old 1.2
Children from 9 to 13 years old 1.8
Persons aged 14 and over 2.4
Pregnant 2.6
Breastfeeding 2.8


References

  1. "VITAMIN B12" , www.webmd.com , Retrieved 23-12-2019. Edited.
  2. "Vitamin B-12" , www.mayoclinic.org , 17-10-2017, Retrieved 23-12-2019. Edited.
  3. Adam Felman (28-11-2017), “Everything you need to know about vitamin B-12” , www.medicalnewstoday.com , Retrieved 12 / 23-2019 . Edited.
  4. Larry Johnson (8-2019), "Vitamin B12 Deficiency" , www.msdmanuals.com , Retrieved 24-12-2019. Edited.
  5. "Intrinsic Factor" , www.vivo.colostate.edu , Retrieved 5-14-2020. Edited.
  6. Emily Wax (2-2-2019), "Vitamin B12" , www.medlineplus.gov , Retrieved 26-12-2019. Edited.
  7. Helen West (7-10-2017), “9 Signs and Symptoms of Vitamin B12 Deficiency” , www.healthline.com , Retrieved 12-26-2019. Edited.
  8. "Vitamin B12: What to Know" , www.webmd.com , 19-6-2019, Retrieved 26-12-2019. Edited.
  9. Arlene Semeco (3-5-2018), "Top 12 Foods That Are High in Vitamin B12" , www.healthline.com , Retrieved December 26, 2019 . Edited.
  10. "Vitamin B12" , www.ods.od.nih.gov , 9-7-2019, Retrieved 25-12-2019. Edited.